eres, See ee ee. age : 4 BRAZOS, AND ROBERTSON COUNTIES. ey eas BY thes t ence Bear - W. KENNEDY. aos gal ce REPORT ON GRIMES, BRAZOS, AND ROBERTSON COUNTIES, By W. KENNEDY. Combes IMaien ab: GRIMES COUNTY, GEOGRAPHY AND TOPOGRAPHY. Grimes forms one of a group of counties lying to the north of and immediately succeeding the great coastal prairie region, forming an inter- mediate plain between that and the still higher iron ore-capped region of Leon, Houston, Cherokee, and other counties to the north and east. This second prairie, as it might be denominated, lies at a slightly higher elevation, and is somewhat more rolling than the primary or coastal plain. The texture of the soils, general geological structure, and topographical features, as well as the distribution and growth of the arboreal vegeta- tion, are also different. Although such differences exist between these two great areas, they merge so closely into each other at places that it is often difficult to de- termine with any degree of exactness where the one ends and the other begins. At other portions of the line of contact the separation is dis- tinctly marked by a series of high, sandy hills, covered more or less by a stratum of coarse, water-worn gravel and pebbles. Such a ridge or dividing line exists along the south side of Grimes county. This ridge begins, toward the south, in Waller county, and rises gradually from 225 feet at Hockley to 245 feet at Hempstead, a distance of 14 miles. At Howth, four miles north of Hempstead, the ridge reaches an elevation of 281 feet, and eight miles further north, near the line between Waller and Grimes counties, it attains its maximum height of over 300 feet above sea level. Crossing this ridge, the county falls gently toward the north until, in “Pe \939 6 GEHOLOGICAL SURVEY OF TEXAS. the region of Navasota, it has fallen to 219-230 feet. From here it again rises gently, at the rate of about 10 to 15 feet per mile, reaching its max- imum, so far as the area at present under consideration is concerned, of 370 feet at Iola, in the northern portion of Grimes county. The country north of Iola continues to rise gently toward the northwest, through Brazos and Madison counties, until the Claiborne greensands of the Wheelock prairies are reached, near the Robertson county line. The portion of this region comprising Grimes county lies south of Madison; Walker and Montgomery counties form the eastern boundary; Waller the south, and the Brazos and Navasota rivers the western lines, embracing an area of about 781 square miles. The topography is extremely simple. The higher grounds are rolling and interspersed with numerous prairies. Low flat ‘‘ bottom’’ lands lie along the rivers and their larger tributaries, and a low range of gray sand- hills covers the southern and southeastern portions. The following table gives approximately the elevations of some of the principal points in the county: Waller county dine 7.502508 eae cca ta elas 6 ine) one ee een eee 240-300 feet. OQOUPEMOY 2h aie a aie aiesa 8 coco fone Were bale ade. « ouaseR enn Oe eRe tale te ae 201 feet. N BV aSObA ee acide acleren se os bus eb Lees a lene nate i a eS ee ee 219 feet. Yarboroug ys poe eee be WW seat view be tise aistociesie ses ae emits ene eee 407 feet. PIaANTErs Ville iso Sais eiseat sy ccese azote Bye ants bin baie alin egal ernest ete 323 feet. ANCUEGrsOn areetae oes She eee ee Weds ee ete wastace berate 2 aie ee 334 feet. PiedMOnP Springs”, 6.1. -amte wa Beg leps wie wee Wkcca ae eae aoe ete el ee 279 feet. Kelluin Springs sscae sete a tee a eee aatae 274 feet. CAwthorn.': so (cides oe vette tee ye Se es Bie Oo ee eee 300 feet. Toda ig ede Wales Cae ee See pee ee cee One ee 370 feet. Bedi a8 isp iy wigs sha as ie SEES hc ees Fei a Cee oe ce eT. ee eee 350 feet. A narrow, slightly elevated, flat-topped prairie region, beginning on the Wm. Burney headright, about four miles south of Anderson, and ex- tending in a north or north by east direction for nearly 20 miles, forms the divide from which the drainage of the county flows in three direc- tions. The waters of the north and south Bedias creeks, with their tribu- taries, flow northeast to the Trinity river. Along the west, Gibbons, Rock, Holland, Grassy, and Beason’s creeks flow into the Navasota and form a portion of the Brazos river drainage system; and in the southeast, Garrett Lake, Indian, Cedar, and several other smaller creeks flow into and form the headwaters of the San Jacinto river. PRAIRIES. The generally rolling character of the country changes in places to broad stretches of comparatively level country and the resultant is the inter- spersion through many portions of the county of numerous prairies of varying areas. GRIMES COUNTY, 7 These prairies change the topography, and incidentally the soil and native growth, and occur almost altogether within the area underlaid by the rocks belonging to the Navasota group. The most important are Wallace prairie in the southeastern, Grimes, Navasota, and Fuqua prai- ries in the central and western, Roan prairie in the northeastern, and An- derson prairie in the northwestern portions of the county. GENERAL GEOLOGY. The geological section shows broad stretches of alluvial or river de- posits extending along the rivers and larger creeks throughout the county. The Quaternary deposits are almost exclusively confined to the south- eastern portion, where they exist in the form of a yellowish-gray sand, intermixed with and overlaid by a coarse gravel. Thin scattering de- posits of this gravel also occur at various places in the northern portion of the county. Underlying these deposits are a series of beds of calcareous clays and sands and calcareous sandstones, which, for stratigraphic purposes, have for the present been denominated the Navasota beds. ‘They rest uncon- formably upon a series of gray sandstones and quartzites, associated with extensive deposits of lignitic sands, clays, and small deposits of lignite. The general dip of all the beds is in accordance with that of the Ter- tiary and later deposits of Southeast Texas. The course is south 30 de- grees east. The dip of the lowermost, or Eocene, division is approxi- mately 50 feet per mile, while the Navasota beds do not exceed 25 to 30 feet at the base, with a general. shallowing or decreasing dip toward the upper portion of these deposits. The general section shows approximately the thickness of the several deposits to be: 1. Recent: River alluvium found along the rivers and large CY COMA erat meth ue date eae en she are aa cae Seale pe kos hee ae 25 to 30 feet. 2. Quaternary: Grayish yellow and brown sands, intermixed with and overlaid by fine and coarse gravel, found in the southeastern section of the county and occurring as small, scattering patches of gravel and pebbles throughout other portions. froma few 1nChes: bois oon scree Sarees es macws 50 feet. 3. Navasota beds: Blue clays and brownish gray sands, contain- ing great quantities of nodules of carbonate of lime, gray and yellowish white calcareous sandstones and sands...... 350 to 400 feet. 4, Eocene gray sandstones and quartzitic sandstones, laminated blue and gray sands and clays, with lignites, occupying the whole of the northern portion of the country, at least.. 1000 feet. 8 GEOLOGICAL SURVEY OF TEXAS. (1) RECENT. Along the western side of the county the valleys of the Brazos and Navasota rivers show a continuous belt of recent deposits, having a width of nearly two miles at the southern end, where it is bordered by the Brazos, and narrowing northward along the Navasota. Along the latter this belt varies in width from a quarter of a mile to one mile. Narrow prolongations extend interiorily along the various large creeks tributary to these rivers. These deposits are made up chiefly of brown clays and grayish brown sands, and in structure present the usual laminated condi- tions found everywhere throughout this portion of the State in areas sub- ject to overflow. Their approximate thickness is about thirty feet. (2) QUATERNARY. The Quaternary deposits occurring in Grimes county consist chiefly of grayish yellow and orange brown sands, intermixed with coarse gravel and small pebbles. In places the sands are altogether wanting, and the deposits are represented by thin beds of coarse gravel and_ pebbles. The Quaternary gravel and orange brown sands occur in the form of a ridge extending across the county along the line of the Gulf, Colorado and Santa Fe Railway. They form a high ridge, separating the several prai- rie regions, and in many places the gravels are found overlapping and mixing with the dark limy soils of the prairies. Quaternary sands and gravels also occur about two miles north of Courtney and in the neigh- borhood of Retreat postoffice, and the sandy portion of them is very heavy in the neighborhood of Yarborough and Stoneham stations, where wells 25 to 30 feet deep do not touch anything else. ‘The same class of deposits occur around Plantersville, and cover the whole of the south- eastern portion of the county. Two miles north of Courtney, on the Courtney and Navasota road, the contact between the Quaternary sand and the underlying limy clays belonging to the Navasota beds is seen in the following section: T Back ROU owas bed ohalesielele aielelalp oil. wiafa ole albobeuctts aes @ ether Sarees mene 1 to 3 feet. 2. Brown sand and-pebblesis; yess). Bike idee eee eee 2 to 4 feet. 3. Blue limy clays containing numerous nodules of carbonate of lime, 2 to 6 feet. Going northward, the gravels, sometimes accompanied with their asso- ciated sands, but often alone, are found in thin, scattering patches. In the neighborhood of Lamb’s Spring, on the upper George Mason head- right, the higher grounds are covered with gravel associated with a yel- low sand, which, however, may be derived from the underlying lignitic deposits. The same thing occurs near Piedmont Springs, on the Moses Evans headright. West of Piedmont, on the James Tuttle headright, the gravel is seen overlying the siliceous sinter deposits as in the following section: & GRIMES COUNTY. 7 1. Coarse gravel (scattering). 2. Dark gray sand, probably derived from the underlying lignitic.. 11 feet. SEP COCU MORE UGE tat ant: ttc gu oe ahi oe ces tecetn Oe OF Fale ethan ote kia wa iunen 4 to 5 feet. At Cawthorn postoffice, on the south side of the Naney Anderson league, and in the region around that place, the gravel overlies a gray sand, and a section shows: PR VEORI Uae ERMC Aa htt a techie aie evens eh cds wale eeams Cas p « 5 feet. ADU Le Pa LI LULC CLAN cise Be these cities eaten lah ee dices ee vies Rares 15 feet. 3. Light gray sand and sandstone, thinly stratified........ eer anne arene 6 feet. Near Iola, on Anderson prairie, the section shows: SLIT RAAT BV ASOLL ete cen eRe ote iad ade minh. e Gea aiedic« foo ales +4 s)eie ages 1 foot. Swell erat Oferavel and, [oscil WOOd 2)... 5. «sense cele nae 6 inches. Ree TaCE TL ea LY CAT Viwieend inset oie ea tees ars nte a haves ec 21 Ste eee oe 4 ne 2 to 4 feet. The belt of yellow and brown sand occurring in the neighborhood of Plantersville extends northward along the eastern line of the county throughout the greater portion of the piney region. Five miles east of Anderson, in the neighborhood of Apolonia postoffice, and for a distance of over five miles toward the south, wells dug 50 feet deep obtain their water supply in these sands. NavasotTa BEps. These deposits have been tentatively classified as the Navasota beds because of their extensive development in the neighborhood of the town of Navasota. Their general section shows them to be separable into two divisions, comprising: a. Upper division: Blue and yellow, sometimes red, clays. with con- cretions or nodules of carbonate of lime, and showing occasional strata of gray calcareous sands and thinly bedded. coarse grained, soft calcareous sandstone, and containing more Cretaceous shells throughout the sands. having a thickness of at least............. 75 feet, b. Lower division: Gray and yellow calcareous sandstones, interstrat- ified with coarse yellow sand, containing many worn specimens of Cretaceous shells and beds of a tufaceous yellow colored silice- ous limestone, having at least a thickness Of.,.............0ceees 350 feet. a. UPPER DIVISION. These beds, as already stated, are made up of blue and yellow, occa- sionally red, limy clays, strata of gray calcareous sands, and thinly bed- ded, coarse grained, soft calcareous sandstones. The prevailing characteristic of the deposits belonging to this division is the peculiar condition of the contained lime. This is usually found in the form of concretions or nodules, varying from two to four inches in diameter, of different degrees of hardness when freshly dug, but easily crumbling to a fine powder when exposed to atmospheric agencies. So 10 GEOLOGICAL SURVEY OF TEXAS. great is their tendency to disintegrate, that in many places they have covered the whole of the exposed surface of the clay bed with a fine white flour-like powder. The area covered by this division les mostly in the southern portion of the county, but extends northward along the eastern boundary as far as the latitude of Longstreet, in Montgomery county, and in places ex- tends westward to within six miles of Navasota. Going south, the same deposits are found in wells at Howth Station, in Waller county, and are also exposed in Linn creek, four miles south of Hempstead. The exact position of the beds is somewhat hard to determine, owing to an absence of good sections; but from what can be seen, the inference is drawn that they form a belt of from twelve to twenty miles in width along the southern border of the yellowish gray sandstones of the lower division. Small isolated patches also occupy depressions formed in the underlying division in many portions of the county. In Grimes county, in the neighborhood of Courtney, the beds belong- ing to this upper division have a known thickness of fifty feet, as seen in the following section of Capt. Christian’s well: 1. Dip very gentle toward the southeast. At Kellum Springs the combined section shown in Chalk branch and at the springs gives the following : POE rary SEDO aR EOL RIN oi oe oes CoE RE 15 feet. | 2. Gray sandstones, thinly stratified with partings of gray sands.. 2 to 6 feet. 3. Lignitic sands and clays, dipping southeast 8 degrees in places, but usually not more than 3 to 5 degrees, and showing a BEEITEOM OT UTICA UIOULS stack ose atte hes vo sd aitinls we wine gis aara'e «she's 5 to 12 feet. 4, Very fine chalky white siliceous sinter and white sand......... 2 feet. ee TVELT EGU RSTACT Wen, i athe Uo levee NRA tus es Massa petoRNG CUR ARIE CONT ctl dea ale 1 foot. 6. Brown lignitic sandy clay ...... cc cee ces e nse cee cece tec ee eee e ee see eee ences Three miles east of Kellum Springs the gray sandstones again appear in a small creek, and the vountry from this point to Roan prairie is cov- ered with gray sand, through which the sandstones occasionally appear. Wells dug in this neighborhood pass through this deposit at a depth of over forty feet. The base of these beds is seen in a creek on the north side of the James Cox league, a little over a mile east of Piedmont Springs, near the old Webb place. The section at this place being: *3—Geol, 14 GEOLOGICAL SURVEY OF TEXAS. Lo. Gravsand’/and Prayer 2 iG ir ener ne mere merieee 8 an ane Damen na 2 to 10 feet. 2. Broken gray sandstone, stained brown on outside and contain- ing casts or impressions of dicotyledonous leaves........... 2 feet. 3.) Blue clay, daminated and join bedin ier is mctaaws yon yee Stans teereet 4 to 10 feet. 4 WELPUg ID ONS SANG. Shoe vse Mase hia wus ang ts ape er eee etuin Ae onan eaten tag 1 foot. Dd. Handy Clay... White wmd SLAIN MOTO Wal sip ok ake sites eek te eae oe 4 to 6 feet. 6. | Laminated) blue sandy clay 7245 ean he nn eal het nee eno ent 5 feet. Tguamina bed: Drown. Bandy cla Wen 102. ste gun cae kick eens een Cen see 5 feet. 8. Urregular deposits ol brown isandstone! ...h 02.0 @ ayes ane bari er ae eerie Broken deposits of quartzitic sandstones occur near the base of these beds on the L. J. F. Mammel headright. Throughout the central area and along the southern boundary of this croup of deposits the sections obtainable are neither so plentiful nor so satisfactory. The general prairie-like nature of the surface of the coun- try, together with the small number of creeks and their generally shallow © courses, prevent the obtaining of sections of any depth. The Rocky creek section shows the sandstones to be prevalent throug- out the whole of that creek’s course. They are soft and inclined to be conglomeritic, with patches of lime in places, and are frequently covered with a black calcareous soil in which a few nodules of lime occur. In this region they also show a thinning out, as wells from thirty-five to forty feet deep are reported to obtain their water supply from a blue clay. On Holland creek, five miles northeast of Navasota, a section shows: EPID ACK SOU so ose ela si s.n ea tage b eb Seles (heehee Rha ken weasel fb Gln eee: tina Es 5 feet. Bi Cera pan PROT Git ly aie id \pomeds a ate, 8a art pies puliaee eee mnt ata tet beetats Rete ote ee a ee 4 inches. 3. Yellow limy clay and thin strata of flaggy sandstone ............. 6 feet. One mile north of Navasota, on the Millican road, the ridge of sand- stone already mentioned crosses the road, and the section shown from the top of the ridge to bottom of a small washout is: 1. Soft gray sandstone, in thin strata at top and heavy bed below. (The thin flaggy division is separated from the heavy bed by a thin seam of calcareous clay one inch thick.)......... 216 feet. 2)'Thin seam ol: calcareous aiavi cen pines pon Ate ees nls ee eee 2 to 6 inches. 3. Indurated eross-bedded yellow sand: . 5... 0... sau. s sean ene ees 3 feet. The artesian well bored at the Navasota ice factory shows a section of: lwurtace soil, dark Pray ands dim yy 2.3). 5 obs 108s sarge oe een 20 feet. BE VVUALLE (CLAY... ss 355 GRIMES COUNTY. WW The record of a well bored at Lamb Springs, on the George Mason headright, near the southern boundary of the lignitic area in Grimes county, while probably not quite as specific as might have been desired, nevertheless shows that the lignitic. strata had not been completely pierced at the end of the boring, as lignite was found at a depth of 939 feet, and that the next sixty feet of the well ran through ‘‘ rock and clays.’” ‘The water contained was strongly saline. This great thick- ness is corroborated by the records of the boring of a well at the Agricul- tural and Mechanical College, near Bryan, in Brazos county. In this well over 900 feet of gray sands and clays were passed through before fossiliferous deposits were reached. The southern boundary of these deposits in Grimes county is extremely sinuous, and, owing to the overlying materials, very difficult to ascertain with any degree of accuracy. Beginning on the east side of the county, the line begins on the Wesley Fisher headright, near the southeast corner of the Evan Corner league, and extends in a slightly south of west course as far as the Gwyn Morrison headright, and thence in a generally south- westerly direction to Gibbon’s creek, where the creek crosses the south line of the Philip Goodbread league. Here the line changes a little more westerly in its course to the Navasota river. The country occupied by these deposits is generally level and covered by prairie-like areas and extensive post oak flats. The sections obtain- able are few and generally shallow. Owing to the objectionable quality of the water found in these sands very few wells have been dug, and any data received from the well diggers are at best unreliable. The few sections obtained in this region show the structure of these deposits to be chiefly sands and clays, with thin seams of lignitic matter and small deposits of an earthy brown lignite. A section on the Jola and Bedias. public road, where it crosses the South Bedias creek, shows: URS TA Ve RAIN VV SOLU ts as ele estat, «ane are os, el ated chatetetaml al MR ante eee cMeta Sha Sisal 1 foot. Dae CMW, EIN y Sead hea) deeds eit ork a latte tate etree eum ame herrea ger stem arse awe AAS 2 feet. 3. Gray laminated sandy clay, stained brown on outside, ee lignitic Streaks fOormine the DALGiee jon Jeteaye te orale tia tease aR ak ase al alah hac 4 feet. One mile south of Iola, in the bank of a small creek running through Anderson prairie, the following section is seen: Pama OTay Sandy SOM Wa cake Oeste ada vacclaeay akan em ale odie. 6,5 at 2 feet. 2. Light gray sandy clay, dipping nearly east................ 1 inch to 1 foot. sark oray, changing toa pale browny sandy Clay Wied oa eee eee ces Between Bedias and Iola the country is flat and prairie-like, interspersed with small motts or clumps of timber, and very generally covered with dark gray sandy soil containing numerous fragments of silicified wood. Near Bedias there are several small outcrops of brown clay and a soft, earthy 18 GEOLOGICAL SURVEY OF TEXAS. brown coal, which form the surface materials over small areas. The soft, earthy brown coal also occurs in the neighborhood of Cawthorn Postoffice, where it appears on the surface, and in the banks of several small creeks. A section on Cat creek shows the following: NIG TAVELA Sate ee tre she Wace He RAN Go ee BAP SNe he te esi ree ee ree Scattering. 2; "Brown Jaminatedscla ys x Ak oe he ees ee ee een nar 2 feet. D. Mong lOmerale Lc. Spa okns sei gat hers akek Glen eieer aie = nae cane 2 inches. 4.) Harbthy.brown coal sina. ton en. vies eee eee ek tenet ae aes 4 feet. 5... Brownish blue. elay to bottom, of creekiV. 4... osama eee ® 8 feet. About a mile north of Kellum Springs a creek crossing the Anderson and Iola public road shows a section of: 17 Brownish’ gray sandy SO Spawn wes ween Came lee oe een a ee 1 foot. 2. Brown clay with lgnitie materialar nts. c wg sec bet hae eee een 4 feet. 5). Harthy brownicoaly iis 3. sieeve 3.5 Galak ge nk ee ae Se 1 foot. 4° Thin Seams Of whitecla yew. cho ksh 4 ate aot nas tan en alee ee eee 4 inches. bi Brown jointed clay. heads SYS a ye yan we elete a tenets ete ee 3 feet. On the west labor of the A. A. Boatwright survey a section shown in the banks of Tanyard branch is as follows: 1, ieurface soll, Pray Band GA. Ses ve nee mie terete eee: ites Siete te eee ee 1 foot. 2. Gray sand yoolay: i) fence & <5) ole’: lakes We areerte ae ots caet te ig ee ee ee 3 feet. Be Gray Clay. wit by corde pe PRRs bee ole epic. eae ep en es 1 foot. 4. Marth y Drown Coal. see. ise cc sie ees ee Re Oe ae ele eee 3. feet. 0 BYOWD COB] stb ates tt scely Sx Reo Gets © cca ae tea en ae ate ee 4 feet. In going up the creek the section changes slightly, and about a mile distant the bank shows: 1, Suriace, Sr ay Sando yc. Ae y Speaens ak aete: en eehe esteaente 7s a ee 1 foot. 2. Yellow sand. 20s “22S, Gee ie ee ea ee ee cetera 114 feet. Dd.» Lhinly Jaminated Drown sandyicla yer, ents es ie ee eee 2 to 6 feet. 4) sHarthy brow COad 0 tire. meme pene ele Death id 0 Sicha dius st A ene 11 feet. bs brown Coal,’ Very-sanld Vian pees te enn ee ee ae 4 feet. In this area the country is very level and covered with a. grayish brown sand containing great quantities of silicified wood, in many in- stances showing its structure. Some of these blocks are very large, and trunks of trees measuring over twenty feet in length and from two to three feet in diameter are of frequent occurrence. _ The presence of this class of fossil wood, showing in its sober gray and brown tints the texture and general formation of the tree, is the more in- teresting from the fact that only two miles southwest of this place the the brownish gray sand had given place to light gray sands and white clays, the contained woods of which are beautifully opalized in white, amber, yellow, and brown colors, some of which show in their glassy structure the original texture of the wood, but in many this texture has been altogether destroyed. GRIMES COUNTY. 19 Going westward, from Iola to the Navasota river, the country is roll- ing and covered with a grayish brown to light gray sand, containing great quantities of silicified wood. Small seams of lignite occur in Bull creek, about two miles southwest of Iola, but these are very irregular and very thin. In no place throughout the wide area occupied by these deposits in this portion of the State has the dip of these beds been satisfactorily ob- served. In many places they shew excessively high dips, and again, within a few miles, the dips have changed to correspondingly low angles, and frequently reverse or northwesterly dips occur for short distances. A measured section at Moseley ferry, on the Brazos, gives the underly- ing fossiliferous greensands a dip of seventy-five feet to the mile, and the same beds on Cedar creek, near Wheelock, have a closely corresponding slope. The gray calcareous sands and sandstones of the Navasota group do not dip more than fifteen to twenty feet per mile. These laminated sands and clays conform to neither of these groups in so far as seventy- five feet is altogether too high, while the maximum twenty feet of the overlying deposits is as much too low. From the records of the different borings obtainable a dip between forty and fifty feet per mile is estimated as being approximately correct. PIEDMONT SPRINGS AREA. During the closing period of the Eocene, or early in the time of the deposition of the newer gray sandstones, considerable changes took place throughout Texas, which resulted in the deposition of an irregular belt of light gray clays and sands, and in places pure white clays associated with beds and irregular deposits of a white siliceous sinter. Deposits of this period occur in Polk county near Corrigan, and on Chalk branch in the northern portion of Walker county, and in other localities west of the Brazos.* In Grimes county these deposits are best developed in the neighbor- hood of Piedmont Springs. Small outcrops of sinter occur at Kellum Springs and on Mr. S. Smith’s land, about two miles east of Union Hill. In the Piedmont Springs area the deposits consist of light gray sands, with great quantities of beautifully opalized wood, sandy clays, white thinly laminated fine-grained clay, and extensive irregularly shaped de- posits of siliceous sinter. A section close to the springs shows: REIT OT AY, CAT nce 2 vit vpceil teal ones AME ees Mae Minerva Oe Ge Uda dhe, a siafa @ 5 feet. wiseoeeray Or pinkish gray sandy Clay we. vata wees Hs stoace oes a apeisic's 2 feet. *In the second Report of Progress, 1891, p. 61, these beds have been assigned to the Miocene, and the same age is also ascribed to them in the Third Annual Report, 1891, pp. 63 and 117. 20 GEOLOGICAL SURVEY OF TEXAS. On. the C. O. Edwards headright, and about a mile northeast of the springs, another section shows: ASO TAy SAD Po. er He MALO ae eilty bk cast he ern ale te See tn tei ori eee ons 1 foot. 2, “1Thinly laminated yellow and ‘brown sands). sole eee tee 2. a tee 5 feet. a, 92 ine-grained laminated white Glay ites nice. siecle cisiate’: alate isket ee gare 4 feet. The surface of the country in this region is covered with grayish white or light gray sands, containing bowlders of coarse-grained flaky siliceous sinter and great quantities of opalized wood of different colors. While the greater portion of the pieces of opalized wood are small, many of them measure from four to eight feet in length and from one to three feet in diameter. ‘These large trunks are very easily broken, and break. with a glassy fracture, although longitudinal sections of from two to four feet are easily obtained. Two miles west of the springs, deposits of a very fine-grained siliceous sinter occur upon the southwest corner of the James Tuttle league and on the W. P. Zuber headright. A section on the Tuttle league shows: Lp CORERG IE VAV ELT Ts oc eicgie ares vie Suatele nie. Gitar an CCR Bie fait iy meee Scattering. 260 Dark eray Sandy sori. seieey cs cieie tee et re al nett ie tes eee 116 feet. S. OLLIVEOUS SINCCT OD hoes A UEAAN Peete bac hp dois aac ere ms ee eerie ean es Beers 4 to 5 feet. This deposit of sinter underlies an area of from twenty-five to thirty acres. On the west side of the same league, and about a mile farther west of this deposit, the bank of a small creek running into Dry branch shows a section of: 1. Gray surface sand with small quantities of pebbles ......:.......... 4 feet. 2. moLtdtine-prain ed teams ai. eek MOLI ee Srey ethos, a Ne meen er ee 10 feet. 34 Broken laminated, blnish!orayiClay: tierce toh woes ve eee stan a ena 3 feet. Ae VAAN ITOS Che 5 Demet ot Fao ne Marae ne a a reece are ae Re 3 feet. Southwest of the siliceous sinter deposits of the Tuttle league there is another deposit of the same class of material on the W. P. Zuber head- right. The sinter in this area occurs in all the creeks and washouts along the east side of the headright, and is overlaid by a light gray sand and gravel made up of pebbles of quartz and jasper, and underlaid by a gray sand, as seen in the following section: , 1. Light gray sand and gravel, the gravel scattering............... 2 to 5 feet. AEOLNCEOUS SINGER, 2h it Jug a eseeeiae Roe Minne ee tp ok a ee 4 to 5 feet. owmaray sand. Visible s.r 20 Pa Re os 2 to 6 feet. Two miles east of Piedmont Springs a cutting on the east side of Sandy creek shows a section of: L.oGray sand ‘with white opalized wood b))).. 7200 le eee 3 to 5 feet. 2, uinivlaminated gray. sand y;clay ii avis an cue eneenn er ae 2 to 6 feet. Going northward to Kellum Springs deposits of siliceous sinter occur GRIMES COUNTY. : AI on the Wm. Fitzgibbon league, and one mile west of the spring the fol- lowing section occurs in Chalk branch, a small stream tributary to Gib- bon’s creek: REST AMCHATIOL ERS te Gli e Oe decd clue Aree tale pictecitees RG ene REPRE LAs emt afaik 1 foot. ESP RAST ULAR TCG: Atl Ch CLA Vo cu cefa wos hea aad a Ghee ae teed aoe Maced toa a 5 to 12 feet. Sates SECO USER LT LET Aah Wry ie oo phy Gh NL Lust atc Me yas Melek aU ag 2 feet. PNY PLY SCR ATTAN CTU ced © Star Jah ele valyg terns a) oleae i at sen ers gem AEE Sa Snatcher oy 1 foot. PMOL MnO TIER EATO Te Clay Gas Lenn ats eee te CaeR Rh a dat sae as alas aly In this region the sinter lies in thin strata or seams between deposits of a coarse white sand, which rests upon a laminated brown sand. The sec- tion shown for nearly a mile southward along the creek is a succession of lignitic sands and clays, alternately dipping southeast and northwest. These lignitic deposits overlie the siliceous deposits. ; This siliceous sinter, which is locally known as chalk, is reported as occurring in small quantities at other places in this region and in the area between Piedmont and Kellum Springs. Five miles northeast of Kellum Springs, on a Mr. 8. Smith’s land, near Union Hill church, there is an isolated deposit of siliceous sinter cover- ing an area of nearly ten acres and having a thickness of over twenty feet. The greater portion of this deposit is covered by a dark gray sandy soil, and gray sands form the prevailing characteristic of the surface of the whole of the surrounding country. Nowhere throughout the area occupied by these beds can the thickness of the deposits belonging to the Piedmont Springs group exceed thirty feet. On the northeastern border the gray sands and sinters either rest upon or are interstratified with the lignitic deposits; and toward the southwest, in the neighborhood of Piedmont, where they attain their greatest thickness, wells dug to a depth of thirty feet pass completely through these beds and enter blue clays containing thin seams of an earthy brown coal. The siliceous sinter found in these deposits is a very fine-grained, soft, pulverulent, snow-white mass, amorphous in places and showing lines of stratification in others. It has a specific gravity of 2. Under the micro- scope the grains are small, rounded, and angular, generally flattened and scaly, and all translucent, some of them being perfectly transparent. Many of the scales are striated and marked in such a manner as to re- semble thin sections of the opalized wood. Throughout the region another grade of sinter is also found. This material usually occurs in the form of concretions, many of which are of large size. In texture it is coarse-grained, and has an appearance very much resembling some blast furnace slags. The origin of these sinters is not yet known. The amorphous condi- tion of the silica and the small proportions of lime and alkalies found in them, as well as the excessive proportions of the alkalies, potash 2.70 my GEOLOGICAL SURVEY OF TEXAS. per cent and soda 4.93 per cent, and the considerable proportion of lime, 2.34 per cent, found in the associated clays,* and the presence of sulphur- eted hydrogen in the springs now flowing throughout the area in which these sinters occur, appear to indicate the origin to be from springs of moderately warm alkaline waters in active operation at the close of the Eocene or early in the stage of the deposition of the Navasota beds, but which are now extinct. These springs probably continued in operation during the earlier por- tion of the Navasota times, and the stratified and assorted condition of the deposits themselves may be the result of leaching and rearranging by water during the period of the deposition of the clays of the upper Nava- sota beds. ‘The causes of these deposits are long since destroyed. In none of the places yet visited do any springs carrying large percentages of silica now exist. The springs in the Grimes county area are all strongly sulphurous and have a considerable flow. These springs, of which the most important are Kellum, Piedmont, and Shanghai, are slightly thermal, and those at Piedmont and Kellum are depositing thin hair-like masses of pale yellow sulphur. All of them give off consider- able quantities of sulphureted hydrogen. In connection with the sinter deposits, a fracture of the strata, or fissure from ten inches to a foot in width, extends across the region in a slightly north of east direction. ‘The actual depth of this fissure, or how far it affects the underlying deposits, can not be ascertained, as through the whole of its length, a distance of several miles, it is nearly filled with soil and leaves of recent origin. This fissure was traced over a distance of three miles, when it become obliterated; but Mr. G. A. Allen, a reli- able observer, states that about twenty years ago it could be traced for over ten miles, and at many places it showed a depth of over seven and even eight feet. The fissure does not appear to be affected by the ma- terial through which it passes, as at one part of its course it crosses a small bed of sandstone, in which the fracture appears as clearly as in the sands and clays found at other places along its course. From this fact it would appear that the fracture took place after the deposition and con- solidation of the sandstones, and that the disturbing cause belonged to a post Eocene time. Whether this fracture had any appreciable effect upon the dip of the deposits could not be ascertained. No exposures in which any reliable measurements can be obtained occur in the vicinity of the fissure, nor in the area occupied by the sinters, and as they lie along or close to the di- vision between the underlying Eocene and overlying newer deposits, between which the dips vary greatly, measurements made at wide dis- tances apart would afford no clue to the matter. * See analyses of clay on page 31. GRIMES COUNTY. b> wo ECONOMIC GEOLOGY. SOILS. The soils of Grimes county, with the exception of the soils of the bot- tom lands, may be characterized as nearly all fit for cultivation, although generally poor. Some portions of the prairies, though usually covered with a thin or scanty vegetation, do not have a sufficient depth of soil for farming purposes, and at other places the gray sandstone formations have no soil at all. The areas, however, in which the rock is exposed are of only a limited extent. Those in which the soil is thin are greater, but still form a very small portion of the county and are generally occu- pied as pasture land. ‘The soils belong chiefly to the two grades—allu- vial, or sedimentary, and residual, or sedentary. The alluvial, or sedi- mentary, are those which have been deposited in and from flowing water, and include all bottom and second bottom valley soils. The residual soils are those which result from the quiet action of the changes of temperature, etc., and are due to the disintegration of the underlying deposits, and consequently have not been removed from their original site, and partake largely of the nature and constitution of the underlying beds. ALLUVIAL SOIL. These soils occur only in the valleys of the Brazos and Navasota rivers, and form a belt of low, flat country, from one to three miles in width, extending through the entire length of that portion of the country ad- jacent to these rivers. Some of the larger streams, such as Beason’s, Hol- land, and Gibbon’s creeks, have wide deltas or bottoms at their mouths, often extending for several miles interiorly along their course. ‘These soils cover nearly one-fifth of the county. Much of this area is subject to periodic overflows from the two rivers, and a very small part of it is under cultivation. The greater portion is covered with a heavy growth of timber. These alluvial soils are mostly a stiff clay, laminated in places, and portions of them have a considerable admixture of sand. ‘They are dark brown in color, and from two to six feet or more in depth. Where in cultivation they are the most productive soils in the county. The chief productions are cotton and corn. Analyses show them to be rich in lime, phosphoric acid, and organic matter, and although the proportions of potash are slightly below the normal, may be considered as of more than average fertility. Analysis of soil and subsoil of Brazos river bottom, Grimes county :* * Analysis by P. 5S. Tilson. 94 GEOLOGICAL SURVEY OF TEXAS. Soil. Subsoil. sae Cnt RD OLUL LDL Se. sea calic We urea ithe Binteie whe auntrclaiieth leslie te dame Musueect re telaiste te SEs .38 .36 Bree TT mole DIG Cede ACR OT Ae Gan eet ON OLE 86.02 81.70 PEDO ODEN): RNGRBUP mS Mey aatiMh aah eT LAA PAR gil as BE TAL a toe cabal 4 69 1.74 TP O10 ie SRO alin Qa cee aitin te euaeele AGE aereatts CRU alah alana tered hia tiara fits 1.64 1.92 PHOSDDOTIG 40C1U Hany ated wae eons eae me ay Nopee stmt h aie cae een g .18 ald PSTN Bre SE an To das Sia Wie ue aay. oe elt Gel nl GUNG COME te eer aoe an ee 4.14 4.89 MME ONOSIO Sais isos ko we poe his iplerche ehh le ale iaia Gls terg al oleataanne Piaieinh cit are ontate trace .29 Potash soluble intwateb.. corto oie ce ee ann eA oe me cet eee 11 14 Soda,, § Soluble in water ci yak UR wllea blanet Nats DINUSS BINA? Aig eels Venere cee eran 02 28 (Insolublerin water. 20au (a Gece aieenehine ae ein armen 21 22 PULP NUTS Ch yi ass ‘as cic mts rapa cleke stare cae Silo kciec tale toc Pa Taner ee aI ne 1.44 84 CTO UG ace S Ce asea ah ohare She a Toren Ree ean eee ieee ace a Sete A tae ae .08 CAarDODIC AGG fn vals tha cae ela le re mice tonic are oes ee een eee 1.60 3.30 OPOANIC MABEGOR UI) Ose Tks Weer ne ae ake mua Rte tenes Otc Niet foc oem en ae. 4.74 99.45 100.19 The cultivation of these soils has a tendency to increase their fertility, by the breaking up of the stiff clay which forms their principal constit- uent, and the mixing of the clay with the brown sand associated with it in such a manner as to form a clayey loam. RESIDUAL SOILS. This class of soils occupy the whole of the uplands and nearly one-fifth of the entire county. In texture and characteristics they change in con- formity with the change of the underlying beds, from which fact they may be graded into four different classes: 1. The grayish brown and light colored calcareous soils, found resting upon the great stretch of limy beds belonging to the Navasota group. 2. The gray upland sandy soil, overlaying the lignitic formations of the northern part of the county. 3. The black calcareous soils, belonging to the prairie regions. 4. The light gray sandy soil, belonging to the Piedmont series. 1. THe GrayisH Brown anp Dark CoLorep CaLcargous Soits.— These soils are found resting everywhere upon the Navasota beds in the central and southern portions of the county. They lie in narrow belts and in broad stretches, between and around the black calcareous prairies. They are generally fine sand, of a dark grayish brown color, intermixed in many places with a dark brownish colored clay, varying in depth from a few inches to two or three feet, and underlaid by yellow and brown clay and sandy clay and sand, and, where shallow, by heavy beds of gray sandstone from one to twenty feet in thickness. These soils are easily cultivated at any season, and are generally early, warm, and well drained, and -when new produce well, but in a few years rapidly deteriorate. Only a small portion are under cultivation. They are usually associated with the black prairies and used for grazing purposes. 2, Gray Uptanp Sanpy Soirs.—These soils occupy the whole of the GRIMES COUNTY. 25 northern portion of the county, and overlie the dark gray sands and clays of the Eocene lignitic, from which they are derived. They vary in thick- ness from one to one and a half feet, and are composed of a fine-grained sandy loam, with a considerable excess of sand of a dark grayish color and easily leaching to a pale yellowish gray. ‘The subsoil is usually a brown or dark brown sandy clay, with occasional deposits of lignitic clay, and in places small scattering patches of gravel. The soil itself is fre- quently intermixed with gravel and small pebbles, particularly in the western part of the area. These soils are warm and early, easily cultivated at any season of the year. They rapidly deteriorate under prolonged cultivation, and in five years are said to lose about one-half of their productive power. Cotton raised on these soils, after several yeais continuous cultivation, is said to lose considerable of its value by the shortening of its staple. An analysis of these soils by Dr. W. H. Melville shows them to have the following composition: Soil. Subsoil. iO HA LOM etl yCTOOMLOTEG Cl ture protest alee ticle Sat. hs arses cuneate 93.70 “LTD SAAT CUTEST RCTS Se SFL ae pea oe! Phan NICHD ar ee tie LR ae iT ST 2.14 12.11 EEE OTIC OLN re Bvt a. Sc) gis b,c atet we onfiae eiste Pandas ane Aly: ameaoae, seatteys O11 008 ETRE eRe es re eRe chee a tea K cade wih ata ator Aldin ed diabwrs eas wea tsus .18 .49 EET ENTCGALCIEL orice AAS Vaikiee erin ete ols OTGIe ard eats clams ylota nicht Guat ow as ba 09 Sr Rae eer ra ie tree ard ot icon Nice aa TENN gles a) Pee Wi Walla: sate, sticiee Manat cae eV a abe .008 .062 CEE MEMD RN Tory an te soem Ss PMR ERY ORCS | teats DRAM LS lata ele toed sal euathte did (es tet 144 24 EROS OM Cay Mac a Pies MAE Mean ot bdl he allie die ajaiidda, Grace ath alee a yeas .08 46 COTO REC CUciemcr mtv a MNCs y's sisi wig sha eared wit sod a lat wena asia aha oh obe Ball a ty 49 1.90 Eee RIV ORO Ms eehtite Gerelee Peale «uals eae Moun ae AE AY oie See's aie eine Clee 09 06 BAPELE VAD E (iets eee em ee ee Rates sie Fal ab ene at taht aie atetd aale eee wee a aha .90 6.46 POEMS RULED Cost LUb arr sre UNIS) goetem adereta Ted. Sy s\e lain scat Neher 4) 2)Aale stele vais oh evelare trace trace SCULLY ne care taay Seapine tie Ae bt). Lares ad weit Sl Mor Mn ay 75 06 WS PEE eae OB iy a en Gre OBER HIE SSR IRI AUPE PPR PEAT SORERWINE Ply iegeag g OEP 1.28 5.46 99.903 99.65 ATG LU VE AOTRWAUCI testes ond Pk areas oe chek seh hain tee cla sate eralniats 36.4 65.9 A mechanical analysis of the same soil and subsoil shows the physical condition to be: —_So0il-—_~+ 7~—Subsoil—, Fixed. Volatile. Fixed. Volatile. ROR MPCMETS LTRS e cte oy ace cecli ne cece eae ieee ace a ea eee 3.66 96 20.16 2.92 TRS GISAIVED coe ass ere) Oe OSH ke aw Ue Bie We eee a 20.25 64 13:95 .90 1h PEG See POCA py RA Le PP RV MiG? 01 81 53.86 1.91 CELE AS CELA 6 ER Mier MRC api ean ia SUM, PACERS gE 10.72 .22 6.16 14 PYRITE ANE BLLCICS oc we wie eld.d SM ae vibkelucouis ale at Capertee 55 4 be eee ee 26 GEOLOGICAL SURVEY OF TEXAS. These soils frequently form extensive prairie regions, such as Jones prairie, near Iola, and others. ‘The quality and texture of the prairie soils differ but slightly from those of the timbered land. Throughout the prairie regions the soil, although classified as sandy, contains a greater proportion of clay, and the subsoil is of a more impermeable nature. 3. Brack Carcargous Soits.—These soils belong altogether to the prairies of the higher lands in the central and southern portions of the county, and are found overlying the gray calcareous sands and sand- stones of the Navasota beds. ‘They are best developed on the Wallace and Grimes prairies, where they occur from two to four feet in depth. They also occur on Roan and Fuqua prairies. The soil is of a black, tenaceous, adhesive loam, varying in thickness from a few inches to four feet. ‘* These prairie soils, unless baked too hard, are easily tilled in dry, but are difficult to till in wet weather. They are early and warm and are well drained.’’* The subsoil is mostly a stiff limy yellow clay in Grimes and Wallace prairies, and a yellow sandy clay in Roan and Fuqua prairies, varying in thickness from two to eight feet or more, and resting directly upon a fine-grained, more or less calcareous, sandstone. This sandstone appears on the surface at many places in all of the prairies, and over extensive areas of Fuqua prairie the soil has been denuded, showing the yellow subsoil. ‘The characteristic structure of these prairies may be summed up shortly. Wallace Prairie.—Lies in the southwestern portion of Grimes county, and covers an area of nearly forty-five square miles, comprising the greater portion of the Caleb Wallace, John Whitesides, Samuel Fuller, Tandy Walker, James Wallace, and Jared E. Groce leagues. ‘The sur- face is slightly rolling and covered with a dark calcareous soil, from one and a half to two feet thick, overlying a yellowish clayey calcareous sub- soil, ranging from two to eight feet in thickness, and both resting upon a fine-grained calcareous sandstone, which appears on the surface in many places. Exposures of this character may be seen at White Hall and along the northern end of the prairie. On the Tandy Walker league the sand- stone forms a ridge from fifty to seventy-five feet above the level of Grassy creek. Grimes Prairie.—Comprises a small area of about sixteen square miles, lying northeast of and separated from Wallace prairie by a sandy ridge which is traversed by the line of the Gulf, Colorado and Santa Fe Rail- way. This prairie includes the whole of the Margaret McIntyre and the greater portion of the Jesse Grimes and Franklin Greenwood leagues. In general features it resembles Wallace prairie. The gray calcareous sand- stone appears upon the surface in many localities, and the soil is black, * Loughridge, Cotton Production, 10th Census, Vol. V, pp. 745-746. GRIMES COUNTY. We calcareous, and about two feet deep. Water is usually obtained any- where on the prairie at a depth of twenty to twenty-five feet. Navasota Prairie.—Embraces the region lying contiguous to the town of Navasota, and covers an area approximating fifteen square miles. The greater portion is covered by a dark brown, changing to black, calcareous soil, from one to three feet in depth. Other portions are covered by a dark gray calcareous sandy soil, closely resembling the underlying gray sands and sandstones. This class of soils is generally thin, and in places the gray underlying beds appear through the soils and form the surface of considerable areas. Fuqua Prairie.—Six miles north of Navasota, between Holland creek on the south and Rock creek on the north, Fuqua prairie occupies an area of nearly nine square miles, comprising portions of the Ephraim Fuqua, William Holland, and Hannah Cornaugh leagues, and a small portion of the northeastern part of the Robert Ray headright. This prairie is proh- ably the most unproductive of all the prairies in Grimes county. In general structure it resembles both Wallace and Grimes, and closely ap- proaches Roan prairie. The gray sandstone appears forming the surface over a considerable portion. ‘The soil is black and calcareous, but has been removed over a considerable area, exposing extensive tracts of the grayish yellow siliceous subsoil. This prairie lies at a much higher elevation than any of the others, and, due to its surroundings, is much more exposed to the eroding in- fluences of rain and other atmospheric agencies. Roan Prairie.—This is a narrow strip of prairie land, lying in a gen- eral northeast and southwest direction from the southeast corner of the Joshua Hedley league, through the Anthony D. Kennard, John Harris, and William McCaffin leagues, and ending on the south side of the Cyrus Campbell league. In length, the prairie does not exceed six miles, and its greatest width is nowhere over a mile and a half. The total area is not more than ten square miles. The surface is covered with a black cal- careous soil underlaid by a yellowish gray sandy limestone. In places the gray sandstone and limy concretions occur in the roads, and about a mile south of the Roan Prairie postoffice occasional pieces of plant re- mains, mostly leaves of a small palm or palmetto, were found in them. Wells dug throughout the prairie supply water strongly impregnated with lime. These prairies— Wallace, Grimes, Navasota, Fuqua, and Roan—all be- long to the same age, and in structure closely approach each other. The succession of black soil, yellow subsoil, and gray sandstones is alike in each, and the general conditions surrounding them are such that the whole may be ascribed to one origin. There is no natural tree growth, 28 GEOLOGICAL SURVEY OF TEXAS. but trees grow very well where planted, and bois d’arc hedges are quite common. Anderson Prairie.—In the northwestern portion of the county a large area, comprising the greater portions of the Nancy Anderson, J. W. Stod- dard, Beverly Tucker, J. W. Scott, and 8. R. Marshal headrights, is known as the Anderson prairie. While the greater part of this might be classi- fied as prairie land, the growth of small post oak and black jack trees have so encroached upon the rest of the area as to destroy its every claim to be so considered. In point of fact, small knots and clumps of trees are springing up everywhere so fast that it will require only a few years to cover the whole. Anderson prairie comprises an area of more than twenty square miles. The prairies are not much in cultivation. They are used mostly as. hay and pasture lands. 4. Gray SANDS oF THE PrepmMont Sprincs ArEA.—These sands form a poor soil, supporting a scanty vegetation, and are not much under culti- vation. Along the eastern border of the county, through the pine regions, there occurs a variety of soils partaking of the nature of the first three classes before enumerated, but under such conditions that it would be difficult to differentiate them. They are generally known as the piney woods lands, and are made up of a mixture of gray and brown sands and blue and grayish blue calcareous clays. Small patches of stiff tenacious black calcareous clay occur scattered through the area, but most of it is covered by a dark brown sandy loam, of a more or less calcareous nature. These piney lands are generally considered the best upland soils in the county. BUILDING STONES. The building stones of Grimes county are wholly of gray sandstones, and belong chiefly to beds of the Fayette division of the Eocene and the lower division of the Navasota beds of the post Eocene age. Possibly a few of the thin shaly sandstones found intermixed with the blue limy clay and calcareous sands of the later Navasota beds may be found suitable for building purposes, but their coarse texture and general want of coherence will militate against any extensive use of them. Apart from their difference in age, the building stones differ consider- ably from each other in their general texture and adaptability, and may be grouped into three classes: Ist. The hard, semi-quartizitic and close- grained sandstones of the Eocene. 2d. The soft, thinly bedded, calca- reous sandstones belonging to the lower Navasota beds. 3d. The granular, coarse, semi-consolidated sand or soft sandstones, interstratified with the GRIMES COUNTY. 29 coarse-grained gray calcareous sands and calcareous clays of the upper beds of the same group. 1. Harp, Semi-Quartzitic AND CLose-GRAINED SANDSTONES. — These occur only in the north central portion of the county, where they appear as a narrow belt, extending from the L. J. F. Mammel head- right northeasterly to the northwest corner of the Biggam White head- right, and from this latter place thin beds extend north and easterly to within a few miles south of Bedias postoftice, on the D. S. Stone headright. They are best developed on the Biggam White headright, where they are represented by a ledge from fifteen to twenty feet high. The rocks forming this ledge are stratified and lie in strata from six to eighteen inches in thickness, and change from a soft gray colored to a hard gray and brownish gray colored sandstone, with occasional blocks showing the characteristic texture of quartzite. Some of the beds are very much broken and tilted in places, and lie mostly in the shape of large bowlders or blocks, many of them measuring from eight to ten feet in length and nearly as many feet in width. On the Mammel headright the same class of rocks occur along the northern edge of the Gibbons creek bottom lands. Here they lie in a very similar condition to that on the Biggam White land, although the blocks are more irregularly formed and much smaller and are of less value as a building material. Intermediate between these exposures the rocks belonging to this group are white and grayish white, evenly bedded, close-grained sandstones. This class occurs in quantities along the upper division of Rock creek on the John Bowman headright. Another deposit is found in the Francis Holland headright, about a mile south of Anderson, on the Anderson and Navasota public road. These rocks lie close to and appear on the surface in many places. They have been quarried both on Rock creek and in the neighborhood of Anderson, and from the smoothness of their grain and closeness of texture admit of being dressed in a fairly good condition, although somewhat limited as to size. The stone finishings of the new court house at Anderson are from the quarry south of that place. 2. Tue Sorr Tuinty Beppep Carcargous Sanpstones. — These sandstones include the beds found in the deposits belonging to the lower division of the Navasota group, and are usually thinly bedded, rarely exceeding six inches in thickness, show a rough surface, and in quarrying break into irregular masses or slabs. Their texture is soft and coarse-grained, in places strongly calcareous, and often inclose small nodules or fragments of white clay. In color they vary from a soft gray to a white or creamy yellow. They are irregularly distributed in the beds, changing frequently from the consolidated sandstone to an uncon- solidated mass of grayish yellow sand, and in this condition form a con- tinuously alternating series of lenticular masses of sandstone and sand. +5--Geol, 30 GEOLOGICAL SURVEY OF TEXAS. The sections exposed in the several quarries are made up of alternate strata of sand and sandstone. Exposures of these rocks occur at numerous places throughout the southern central portion of the county and in the neighborhood of Nava- sota. The exposures seen near this place form a ridge extending from near the Navasota river in a northerly direction, skirting the river bot- tom to Holland creek, a distance of about four miles. This same ridge then passes up the south side of Holland creek to the crossing of the Navasota and Anderson public road, where the sandstones are exposed over an area of several hundred acres. These rocks also appear on Grimes prairie and near White Hall postoffice and several other points along the northern side of the prairie. Sandstones in the neighborhood of Navasota belonging to this group have been quarried for building purposes for a great number of years. They are used in Navasota as building material almost exclusively. They are also said to have been used for the manufacture of lime many years ago. 3. Ufper Navasota Sanpstones. — The soft gray semi-consolidated sandstones of the upper division of the Navasota beds are almost alto- gether unsuited for building purposes. Fairly good rock may be found occasionally throughout the beds, but the quantities are so small that these sandstones can not be considered as of any economic value. CLAY. In several portions of Grimes county deposits of clay exist in greater or less quantities, and in qualities ranging from the ordinary brick earths to a grade suitable for the manufacture of the ordinary or even finer erades of earthenware. Some of the limy clays might also, with careful selection and cleaning, be utilized for the manufacture of a fair grade of cement. Brick clays or earth occur at different portions of the county, but no steady brick making industry is carried on. Near Navasota a yellowish brown earth has been used for brick making purposes at intermittent times for years, and the bricks used in Navasota for building and paving purposes were made in this yard. ‘These bricks are very hard, and of a brown color, more or less spotted with blue iron stains. Dotece a See eee Bete ra Bw Een ees ets ete ce 1 foot. These deposits lie apparently in an unconformable manner upon the fossiliferous greensand marls belonging to the Claiborne group proper, as shown in the Moseley Ferry and Cedar creek sections. 3. Brown FerruGinous GREENSAND MARLS, GREENSANDS, AND GREEN- isH Brus Crays. — The lowest deposits found in Brazos county are a series of brown ferruginated greensand marls, greensands, and greenish blue clays, with occasional thin beds of irregularly deposited lignite. The beds belonging to this series form a western extension of the Cook’s Mountain series of the upper marine Eocene, and approximately lie in the same horizon as the beds found at Alto, in Cherokee, and on Hurricane bayou and Alabama bluff, on the Trinity river, in Houston county. ‘The Brazos county beds, like those of corresponding age east of of the Trinity, contain an abundant and well preserved fauna. ‘These beds have not yet been connected stratigraphically with the Houston county or Trinity river beds, although they have been traced from the Brazos eastward across Brazos county to the Navasota river, and for a short distance into Madison county. ‘They are also known to occur at several intermediate points in Leon county. Paleontologically, as well as as lithologically, the Houston county beds present a strong affinity to those of Brazos county in several respects, more particularly in the occurrence of the Spirorbis leptostoma, Swain, and Plicatula filamentosa, Conrad, as well as several other species. The former of these fossils was described in the Houston county beds under the name of Vermetus, a name now found to be incorrect. These two fossils appear to be the characteristic forms belonging to the uppermost beds of this horizon, and occur in great numbers at all the places where the beds are seen in Leon, Madison, Robertson, and Brazos, as well as at Alabama bluff and Hurricane bayou. These beds immediately underlie the gypseous clays and sands forming BRAZOS COUNTY. 51 the base of the Yegua or lignitic division of the Claiborne, and the want of conformity noticed towards the eastern portion of the State, in Chero- kee county and in Houston county, is also noticeable in Brazos county. This want of conformity between the greensands and the overlying lignitic or estuarine deposits is marked in Brazos county by the presence of boulders of altered fossiliferous sandstones found occasionally im- bedded in the lignitic sands. Five miles north of Bryan, where the Bryan and Hearne public road crosses the south prong of Thompson’s creek, a section showing the pres- ence of these fossiliferous boulders in the lower portion is as follows: PUERCO AVEOAUU ESOT Wee eter eee aver ege eee Te tole De eae fee 1 foot. MMI AT EOL EVE CATIC VORULISOLL Pie tele Gives So Crude tock MOU ee Cen Tat hes 114 feet. 3. Yellow and brown stained sand, containing quartz and ferrugin- ous gravel and silicified wood in lower division ............. 2 feet. 4, Thin broken stratum of fossiliferous sandstone ................. 8S inches. 5. Yellowish gray sandy clay, with boulders of iron containing casts of Cardita planicosta and other fossils, visible .......... 4 feet. The well boring at the Agricultural and Mechanical College entered a dark blue fossiliferous clay at a depth of between 900 and 1000 feet. This represents the blue clay No. 5 of the Moseley ferry section, and not the upper beds containing the Spirorbis leptostoma and Plicatula jilamentosa seen near Benchley, which, had they been present in this locality, should have been found in the boring at 650 feet. These sands with their ac- companying fossils were not found, and from their absence it may be inferred that about 250 or 300 feet of fossiliferous greensands and clays had been removed by erosion before the deposition of the gray sands and gray and blue lignitic clays. The portion of the beds belonging to this series found in Brazos county occupies a narrow belt not exceeding four miles in width at the north- eastern end, and five miles in the southwestern or Little Brazos area. This belt extends along the northern end of the county in a generally southwesterly direction as far as the Houston and Texas Central Railway in the neighborhood of Benchley station, whence the line of contact be- tween these and the overlying Yegua or lignitic beds turns in a southerly direction and extends in a line approximately parallel to the course of the Little Brazos river, crossing the Brazos about half a mile south of the confluence of the two rivers. The country occupied by these deposits, in the northern part of the county, forms an extension of the great Wheelock prairie, and is level or slightly rolling. Towards the western portion, the country becomes hilly and rough, showing a series of rugged bluffs along the eastern bank of the Little Brazos river. In the western portion of the county the sequence of these beds is best 52 GROLOGICAL SURVEY OF TEXAS. seen in the section shown in the bluff on the western side of the Brazos river at Moseley’s ferry. The section is: 1. - Cae LR ee e. asda es 2to 4 feet. op aininaved Uniossiliferous Clays.is.%.. ¢. 2. ¢e eee 4 feet. 4. Pale Dlueolay,untossiliferous.....0i..% . aon See ee 1 to 3 feet. * American Journal of Science and Arts, Vol. VI, second series 1848, p. 23. BRAZOS COUNTY, 58 5. Thinly laminated blue to black fossiliferous clay.............. 6 feet. Goat. Hih scram Or Losi LIGrOusarOD OTe... <. ee eas ees ee ba edn 1 foot. Pee OPS CEOUB LAT OCR CIA) in Sia waists. e wales < Shvisialince hen 65s .e.e9 se Se 3 to 8 feet. In this place the section shows the Eocene deposits to be in contact, although unconformably, with the drift gravel, and the gravel itself overlaid by 10 to 15 feet of river alluvium. Five hundred yards south of the:mouth of the Little Brazos river a section of a bluff near Wellborn shoals shows: Pees TAGE MSO Lette n taseerennes eu pcm cacrene eee tin toro ela ES ar a ear ie a eee Pee 2 feet. BeeOrOW ie lO“ni. WIth MIN y COUCTCLIONS.'. 2.0 yi + . an Ee a Gate lele ole 0 a 60 6 6 ela, oe ik Ree EE ee, 314 feet. PBL CL aes elcren as of Seah e aix ee oi sv iw) 8 Se > SPACER eevee ee ee reer 337 feet. Bremoud?.. >. ae RE RASS Co no, Ge me 467 feet. PEN Ne Oe 2 oe ae PET eee EEE Peon kk oo rl Xe 470 feet. ROBERTSON COUNTY. 61 The drainage areas are unequally divided into an eastern, or Navasota river basin, and a western, or Brazos river basin, of which the Brazos is the larger. ‘The divide is formed by a narrow, irregular strip of higher land, not more than two miles wide at its greatest breadth, and frequently cut almost through by the headwaters of the various creeks. In places this divide is occupied by small prairies, from which the water drains in- discriminately towards either of the basins. The ridge, if it may be called such, extends in a general direction nearly north and south from near the southwest corner of Limestone county to the old San Antonio road a few miles west of Wheelock. The eastern section is drained by the Navasota river and its tributary creeks, viz., Steele’s; Red Oak; Duck, with its tributaries Stone Coal branch and Mineral creek; Camp, and the two Cedars. With the excep- tion of Welch’s bayou on the John and Joseph Welch leagues, no streams flow into the Brazos river proper, and the whole of the drainage of the western side of the county is collected from the different creeks by the Little Brazos. The creeks tributary to this stream are Walnut, with its subsidiary streams Birch, Middle, and South Walnuts; Sandy, Muddy, Pin Oak, Spring, and Campbell creeks, with Peach and Elm as branches of the last named. | With the exception of Duck and Big Cedar creeks on the east and south, and Walnut, Muddy, and Pin Oak on the west, the creeks of the county are all comparatively small, and dry throughout the greater por- tion of the year. These larger creeks maintain considerable streams of water at all times, except during a small part of the dryest season, and even then water can be found in large pools at different places in the creek beds. : The Little Brazos river marks the eastern extension of the bottom lands belonging to the Brazos drainage, and itself maintains a peculiar relation to the main river, in so far that for a distance of over forty miles it pur- sues an almost parallel course, from the northern side of Robertson county southward to its junction with the larger stream in Brazos county, about ten miles south of the line. The two channels are scarcely more than two miles apart through the whole of this distance, and nowhere do any streams intervene. The eastern bank of the Little Brazos is formed of a series of small bluffs, from twenty to twenty-five feet in height, which at places approach the river, and at others recede for one or two miles, but in either case are usually quite steep, and show more or less the general structure of the country to the east. *7. Geol, 62 GEOLOGICAL SURVEY OF TEXAS. GENERAL GEOLOGY. The geological section of the county shows great stretches of recent alluvial deposits extending along the rivers and covering an area along the Brazos from two to four miles in width. Small patches of quaternary sands and gravels are found overlying the higher lands among the ridges. In the south and southeast the greensands and marls of the Moseley ferry and Wheelock sections predominate, and in the central and northern areas the Eocene lignitic and basal beds constitute the characteristic strata. The general section shows the following approximate thickness of the several deposits:. Recent: River alluvium, found in the flood plains of the rivers and creeks and some of the second bottom lands...............-.00- 30 to 50 feet. Quaternary: Gray and brown sands, brown conglomeritic sand- stones and siliceous gravel, found along the ridges in the central portion of the county, and also underlying th_- river alluvium of the Brazos valleys... sca. Be ciot 2. ee see een ee eee 20 to 50 feet. Tertiary: Altered glauconitic sandstones, brown and green fossil- iferous sands. green, blue, and dark gray fossiliferous clays, dark gray laminated sands and clays, with thin deposits of cal- careous and fossiliferous sandstones and brown coals, and a basal series of dark gray and green fossiliferous sands and clays, with fossiliferous calcareous bands and nodules................ 1400 feet. RECENT. A considerable extent of Recent deposits occurs along the western border of the county, comprising the region lying between the two rivers, the Brazos and the Little Brazos, and occupying an area from two to four miles in width, extending from Brazos county on the south to Falls on the north. The structure of these deposits, where undisturbed, is to a great extent laminated. Deposits of brown clays and sands, in lamine, having an irregular thickness and no perceptible dip, form the great bulk of these beds. In close proximity to the Brazos river the clays are scarcely represented, and the alluvium is made up chiefly of brown river silts or fine sands, having occasional small pockets or thin sheets of a coarse sand or fine gravel. The structure can best be seen in the sections obtainable at various places along the Brazos river. A section seen on the river six miles southwest of Calvert shows: MES TOW SAV ABOU 000 3 feet. 4. Dark humus, with interstratified or interlaminated deposits of WL WIR RaT Cl be se eines at one toc ak aed Ueiaaaas witte Ye arcs 8 feet. Or DAV DEOWINSAHC, settee e aera Pak er wate ties fs aly heat eels eens’ tis aah en 6 feet. Gos DIAOKPClay oe aes od: MME Gre PRR URE ds Palas vd APSR eS ole maleate os 10 feet. 7. Dark blue clay, weathering yellow, containing great quantities of THEN VECONCFCLIOUSS COONVALCI: cats canaries ewe see eect ee kd oe oe ate 6 feet. Nos. 6 and 7 of this section do not appear to belong to the Recent de- posits, but to the upper or middle Quaternary. On the eastern side of this alluvial tract, a section near Dr. George McLendon’s gin shows the brown river sand overlying Quaternary gravel and lignitic deposits: dae OrOwImsane yy Tiver Critt,andi soll yn: cae cee ed eeale Goce ede 10 to 15 feet. Beh orrurinous and quartz CTAVe! 5 his cach ce hots oe eeee aus’ 2 feet. 3. Thin bed of brown sandstone, containing plant remains..... 114 feet. Se ORV TATU INAUECE MIST IOLO BANG cect y sae cc etk a cc fee oo otras B 1eet, Dopp LO Wil CORL Sot e tan wrieln cities at che Potse os moe aed cals eee Ae oe Sm feeb; From these sections it would appear that the whole of the area is sub- ject to overflow, and that these overflows are very intermittent and fre- quently at such long intervals apart as to admit of the formation of a surface soil in many places between the successive flooding. These deposits nowhere exceed 35 or 40 feet in thickness, and the fauna is altogether of shells of species now living in the Brazos valley. QUATERNARY. The Quaternary deposits occupy but a limited area, and admit of a division into two periods—a lower and an upper. ‘The lower division is composed of gray and brown sands, brown conglomeritic sandstones, fer- ruginous and siliceous conglomerates, and ferruginous and quartzitic gravels. This division is found along the ridges in the central portion of the county, and underlying the upper clay division throughout the Brazos river valley. ‘The second, or upper division, consists of a bluish green clay, weathering yellow, with numerous limy concretions and con- taining recent shells, some species not now known to be living in the Brazos valley, and several not known to be living in the State. ‘This class of deposits occurs only in the valley of the Brazos river. 64 GEOLOGICAL SURVEY OF TEXAS. 1. Lower Deposits.—The deposits belonging to this class occur chiefly in the higher regions of the southern, central, and southwestern portions of the county. They also occur as thin scattered gravelly sheets, of a few inches or less in thickness, in places in the north central and western areas. Deposits of brown sand and gravel occur at various places among the bluffs along the east side of the Little Brazos, and gravels and con- glomerates belonging to these beds are also found underlying the allu- vium and bluish clays of the upper division everywhere in the district between the Little Brazos and Brazos rivers. Large quantities of gravel and brown sand occur in the neighborhood of Sutton. Eight and a half miles east of Hearne, on the Hearne and Wheelock road, a section of the highest portion of the ridge shows: 12; Red.sand-and ferruginons oravele sss pecan eee 4 feet. 2. Mottled red'and“eray sandyiclay ye... ce ele e ane ek eee ae ee 70 feet. Three miles nearer Hearne, on the same road, a section shows: 1. Gray andy S01] tesa iss. eso bbe peels on det ee ee eee 6 inches. 2.) TOW ISAD Cg atic di ncoyae lche wreleun sete era age oinseke sb) siete peer Riel tea eee 5 feet. 3. Light gray almost white sand, with indurated laminz........... 2 feet. 4, Irregular deposit of ferruginous sandstone ................... «- 116 feet. S Indurateddaminated brown sand .< 3) 62.00 bus Seri) eek ee 2 feet. 6saPale pink sandy) CIAY F564 ec yeh s sy ee ge oe ee ie ee eee 12 feet. Throughout the region embraced by these sections heavy deposits of gray sand and boulders of ferruginous conglomerate cover the whole area; and one and a half miles south of Hearne blocks of conglomerate, many measuring 10x8x5 feet, made up of brown sand and siliceous peb- bles cemented together by a ferruginous matrix, form a ridge extending southward for over a mile. In the neighborhood of Hearne the conglom- erate gives place to a soft brown colored sandstone containing streaks or small pockets of coarse sand or fine gravelly conglomerate. The same grade of sandstone is also found stretching along the south bank of Muddy creek from the Denver James headright eastward. A section on this headright shows: SA TAV OL ee cis etic cs sea wisolt sae as eee Sa eet eee eee Scattering. sl De COOMSTOMONATE ES ic. tie is sys barb ob lee etre Sadeatieny tle eer eee ea 2 feet. 3. Ferruginous sandstone, with pockets or streaks of conglomerate 4 feet. A SSSEC OCU RAIL FF ee eit eh a'borr ona, <0 4. § Vina wt Soe eve wea ab ete te We bs alate ee EE CR Ra 3 feet. 5. Yellowish gray sand, with streaks and pockets of white sand... 40 feet. This sandstone ridge, with its capping of gravel, extends in a nearly north direction to the west side of Little Muddy creek, on the south side of the Henry Reed league, where the sandstones disappear under a heavy deposit of loose gray sand. South of the International and Great Northern Railway, in the neigh- borhood of Hearne, another ridge begins and extends northeast to Frank- ROBERTSON COUNTY. 65 lin. In going eastward along this ridge conglomerate and sandstones occur on the crests and sides of the hills, and in the vicinity of Franklin they are extensively developed. ‘The country to the south of the town, surrounding and forming Racetrack prairie, is occupied by a series of small rounded hills or ‘‘ knobs’’ covered with blovks of ferruginous con- glomerate. These conglomerates, with their associated brown sands, also appear close to the town, three miles northwest of Franklin, on the Cal- vert road, and throughout the surrounding area as far west as Little Muddy creek. The country is broken and irregular, and covered with a deep bed of loose gray sand, through and among which boulders of fer- riginous sandstones and conglomerates appear plentifully. A section on the east side of Little Muddy creek shows: len -Brown. ferruginous, sands and gxvavelirs «5 .sjit yao e's ol oa eve byagere'e eure hadi 2 eet. 2. Brown laminated sands and soft sandstones ..............2 eee eees 114 feet. Serra y HatlinAced JUICACCOUS. BANOS. owu)..c as ce each cWe ok who ween + Chas 8 . feet. The gravels of this age spread over the lower lands throughout the central and northern portions of the county, but generally occur only in thin sheets of not more than a few inches in thickness, and accompanied with deposits of brown and yellow sand. A section near mile post 124 on the Houston and Texas Central Railway shows: APMIS ECW EM S QING Lee acters cris deca a MS rade tim & dis'a’yuetal sere a eee 1s to 3 feet. 2, Fine gravel, with streaks of coarser gravel and occasional small nodules, changing to a coarse brown sand with streaks of Wneeravel neste: POCO MAs Niele aii 3 48S. oe le. Cokie 5 to 7 feet. Pom Later DUG MAIL VST LC Yorn Ain ap ta et ece ako ome ccd = nase wast ys ake l¢ to 1 foot. Near mile post 134, on the same road, another section shows a series of brown sands and gravels as follows: ee LAIMStratusOL Oro Wi sand. and, Oraveli.c i. cor siamese le cae « 1g foot. 2. Light brown sand. (This bed thickens toward the south, and replaces a brown gravelly sand 400 feet from the south end of BUG CULES ae eee. eee a eae aie tLe ar sal oe Matnimnra ne edt e 1 to 4 feet. 3. Brown gravelly sand, 8 feet thick at the north end and thinning CiteOULO WAL S sice' aryauie ates Soon nin'e Pateuls sect shay ashanti deve ae 1 to 8 feet. 4, Gravel. Wedge shaped deposit, heaviest at south end, lying near center of the cutting, and 50 feet in length............. 1s to 2 feet» Gmeecawi eravelly sand; SAMeG ASIN Oe dus ve w. sss erica ae cee. | os 0 to 3 feet. These sections may be duplicated in many other portions of the county. Gravels and conglomerates occur at many places in the bluffs along the banks of the Brazos river. They underlie the brown river alluvium and bluish limy clays of the succeeding deposits. The conglomerates are mostly siliceous, formed of pebbles of quartz, silicified wood, and lime- stone, with great quantities of nodules of a white calcareous clay, ce- mented together by a silicate of lime. They contain numbers of worn 66 GEOLOGICAL SURVEY OF TEXAS. Cretaceous shells, shark teeth, and occasional vertebrate remains, mostly of the Equus family. A section at Curley shoals, six miles west of Calvert, shows: 1. “Brown river'silt and Sands. i2 sci. ease ace ee eee einen es cere eee 5 to 10 feet. 2. eGonvlomerate,; (2756 a. 55 26 one. ent ae we tee Oath eiceln oe eee eee ere 4to 6 feet. 3: Palelue Clayc. Jsatukowses sh yesh da biiee sera an is heen imine 1 foot. 4. Micaceous bliesands ..0 ise .cs sees + pian t meeaied piace ane e een eee 3 feet. 5 Gray calcareous sandstone... .2sc cb sence s ERs eee eee 4 feet. 6. Grayisn. bluersand 23 vaccscas aseaee natin ace shake aes eee een 2 feet. 4, VGPSY BANASLONC SOVOL. oi." ra eo ae gis a eh ah anne uces sarees otal 2 feet. At this point the shoals are formed by a heavy ledge of gray sandstone (No. 7 of section). The conglomerate is made up chiefly of siliceous pebbles and blocks of limestone from the Cretaceous beds found farther up the river; occasional nodules of iron, and great quantities of worn Cretaceous fossils of the Gryphea vesicularis type, the whole cemented into a solid mass by a silicate of lime. Fragments of the tibia of a horse were found imbedded in one of the larger blocks, and considerable quantities of nodules of calcareous clay are scattered through the whole mass. 2. Uprrrer Diviston.—The upper division of the Quaternary deposits was Only observed in the Brazos river valley, and comprises a series of deposits of bluish green clay, weathering yellow, with numerous limy con- cretions containing shells of recent species and species not now known to be living in the Brazos drainage area, and several, such as the Limnea refleca, Say, and Pomatiopsis lapidaria, Say, which are not known to be living in the State. The latter occurs in the Post Pliocene of the Missis- sippi river bluffs. * The deposits belonging to this division have been noticed at several localities in the Brazos river valley, from the south side of Brazos county northward to near the Falls county line. They have the peculiarity of appearing in small embayments, on both sides of the river, and gener- ally in alternate positions, indicating that at the time of their deposition the river, although approximating its present position, was flowing through a channel widely differing in its curves. These clays appear overlying the gravels in every case where the two have been found asso- ciated, whether cut through by wells or in the river bluffs where the channel has been cut deep enough to expose the underlying deposits. The position of these deposits is seen in the following section of the bluff along the east side of the Brazos at Port Sullivan shoals: * Of one of these shells, Mr. J. A. Singley, to whom they were referred, says the Pomatiopsis lapidaria, Say, has a distribution from Georgia to New York, Missouri to Michigan, Post Pliocene of the Mississippi river bluffs. No recent record in Texas or adjoining States, and this I think establishes the fact that the clay from which it is derived is Quaternary. ROBERTSON COUNTY. 67 PARLE OMGIY BELLS He. sles Weod Wie le Pee Cele gid Ste «ele iis Klis We ole Hk hie ee 1 foot. 2. Laminated chocolate colored and yellow stratified sandy clay, RDU SLA teh thle RRO eee aginee irs tO See Oats Oe Ol ohg faictd’s ens ab ay 2 feet. 3. Dark brown or chocolate colored sandy clay..........cecseseee 8 to 10 feet. 4, Dark bluish gray sandy clay. weathering yellow and containing fragments of bone and shells of recent species and others .... 10 feet. 5. Indurations of sand and soft sandstones in the form of boulders. 1 to 2 feet. WEMSBSVGL RUE e Celie tnt Lhe cts ad os hh ae tal yeh ew mand iba ier dein 1 foot. 7. Laminated dark greenish black sand to water.................. 2 feet The bone fragments found in No. 4 are mostly in such a comminuted condition as to be unrecognizable. In one instance, however, we ob- tained a lower jaw and teeth of a horse almost entire. TERTIARY. The Tertiary deposits of Robertson county belong altogether to the Eocene division of that period, and represent three distinct stages of that group, and may be divided as follows: Series. Division, ae ven Characteristic Strata. ( (Marine. >... 600 |Fossiliferous greensands, marls, and fossiliferous clays. Eocene. < |Lignitic ...' 550 /Lignites and brown coals. ae beds..| 250 |Fossiliferous clays and sands and limestones: | calcareous sandstones. Areally, these deposits cover the whole of the county. The basal beds occupy a small territory in the northwest corner, the lgnitic deposits stretch across the county, in the form of a wide band from eight to twelve miles in width, and the upper or marine fossiliferous sands cover about one-half of the county. The dip of the beds is in a general direc- tion of south 20 to 30 degrees east, and at varying angles, ranging from 0 to 1 degree. Basa Beps.—The deposits assigned to this division occupy but a very small areal extent in the northwestern portion of the county. The terri- tory is generally level, and so covered with surface deposits of gray sand and river alluvium that few exposures of the underlying beds can be seen anywhere. ) These beds differ in lithological character from the clays at Wills Point. In this locality the deposits are not so regularly laminated, and contain a much greater proportion of sand and sandy strata, and are also more fos- siliferous. The basal beds as represented at Wills Point consist of yellow laminated clays, with thin partings of yellow sand, containing occasional boulders of siliceous limestone; massive bedded clay, showing no signs of lamination; and dark blue laminated much jointed clay, with thin sandy 68 GEOLOGICAL SURVEY OF TEXAS. partings, containing occasional small bivalve shells, and showing a heavy bed of white limestone containing great quantities of fossil casts.* The . basal beds as represented in Robertson county comprise a series of thinly stratified yellowish gray sands, and grayish blue laminated clays and sands, with broken strata of grayish blue fossiliferous siliceous limestone, and occasional rounded and flattened boulders of gray calcareous sand- stone. The blue siliceous fossiliferous limestone possibly represents the same horizon as the white limestone found at Elmo and Rocky Cedar and Kemp, in Kaufman county, and at Tehuacana, in Limestone county. The dip of the beds is toward the southeast, and very gentle and undulating. In places they present long stretches of almost horizontal strata, suddenly terminating in a downward flexing of the beds, which, however, continues for only a short distance, when the practically horizontal bedding is again resumed. ‘The following sections seen on the western side of the Brazos river will show the general structure of these deposits: I. Section on the northeast corner of the Byrum Wickson league, Milam county: 1. Ver AVION ne cs te eee 4 dNG Rese ce UNI A E ER ee 4 feet. 2 Cong lomergte. tse aie nes “nip Wad, ed oe ee MR eee ae ae 2 feet. 3.-.Coarse conglomerate, with Douldere..o 2. t.3e eee ee ee 114 to 2 feet. 4, Thinly stratified yellowish gray clay, sand, and blue clay, with occasional rounded boulders of calcareous sandstone........ 10 feet. 5. Blue Taminated: clay, fossiliferous v.06 .5. 72. wae wee oaltae ates 4 feet. 6. Thin bed of nodules and hard fossiliferous limestone......... 1 foot. 7. Thinly laminated yellowish gray clay and sand.............. 3 feet. S. oDINish Pray and. Vasa os aka ck ie citi ar oek eae ee ee ee 1 foot. 9. Thinly laminated dark blue clay and sand................-.. 6 feet. 10. Dark blue laminated and fossiliferous clay................... 2 feet. II. Section on C. Cribbs league, between two and three miles north of No. 1: 1. spurface soil, brown,sand and /oravel yk. voc. cea ek dee eee 2 feet. BOL OUOW-GISY. see as ROTO NEES OT LO ty ar ea Soe A 4 feet. 3. Ledge of fossiliferous siliceous limestone...................05: 2 feet. Aa GUOW Clay, SAIC. BEND. D phos ane t Corte ec counts ae nee eewencre 5 feet. BF copmne tag WN DAB: ada sae vine cul here aan eae Ee eee ee ee eee 2 feet. 6. Dark blue thinly stratified clay, showing lines of lamination on weathering sandijointeds.1. 0 wis fino, Sah wets tne ne eee 30 to 35 feet. The dip is very gentle towards the southeast, and in places along the bluff shows the undulations referred to. Going still further north into Falls county, the base of these beds is seen in contact with the underlying Cretaceous deposits in section No. III, on the southeast corner of the Josiah Hogan league: *Penrose, First Annual Report Geol. Survey of Texas, pp. 19-21. Kennedy, Third Annual Report Geol. Survey of Texas, pp. 48-49. ROBERTSON COUNTY. | 69 bo SUL SRV Ol men NR on oe Paes Litt cou Use aie nla ic ped tebe sicko a Hie eB rie 1 foot. 3. Blue clay and sand, breaking into nodules and conchoidal pieces, weathering to a grayish yellow, and containing in the upper half Calyptrophorus velatus, Conrad, Cucullwa macrodonta, Whitfield, Os- trea pulaskiensis, Harris, and others; and Cardita alticostata, Con- rad, Pleurotoma, sp., Yoldia, sp., and Crassatelia, sp., in lower two BHU ase LCObr ce ue oe cca ae ete er an Oat er ho ant. gars is ta 5 feet. Pe POLSILIOT AL DIO CA tee Th de ec hs ial ated was aleX was tag ote ce ep 1 foot. 5. Massive blue clay, with baculites and other fossils.................. 14 feet. Lienitic Beps.—Succeeding the basal beds comes a series of interlami- nated, interstratified, and massive dark gray and dark blue sands and lignites, interstratified with beds of dark bluish gray calcareous and siliceous sandstones and brown fossiliferous sandstones, the blue and bluish gray sands predominating. In the eastern portion of the county a small section on Mineral creek shows an exposure of the blue and red thinly stratified or laminated sands and sandy clays belonging to the (Queen City beds of thisseries. In the west these beds do not appear in any of the sections seen. The beds belonging to this division form a continuation of the great . lignitic beds lying near the base of the Eocene in this State, and stretch- ing from the Arkansas and Louisiana line southwestward across Texas. They enter Robertson county from Limestone on the north and Leon on the east, and extend in a general south by west direction to the Brazos river on the western side. The lignitic sands, sandstones, and clays, with their associated beds of brown coal and lignite, cover an area approximating 340 square miles, or one-third of the entire area of the county. A line drawn from near the mouth of Pond creek in a northerly direc- tion through Hammond, Wooten Wells, and Bremond, or almost parallel to the line of the Houston and Texas Central Railway, will approximate the northern boundary of these beds. Toward the south they pass under the succeeding beds of the Marine Eocene along the south side of Muddy ereek, and on Mineral creek about four miles east of Franklin. Along the southern margin few exposures of the contact can be seen, owing to the whole of that area being more or less covered by Quaternary brown sands and gravels. This boundary may be drawn approximately from the Navasota river, near the crossing of the International and Great Northern Railway, westward to Mineral creek, and thence to Owensville; thence in a general west by south course to Muddy creek, and then along the north side of that stream to the Brazos river. The region underlaid by these beds is generally level or slightly rolling, and is more or less covered with a scanty growth of timber. Numerous * Determinations by G. D. Harris. 70 GEOLOGICAL SURVEY OF TEXAS. small prairies, such as Tidwell, Beck, Head, Heard, Bald, and others of smaller extent, occur throughout the northern and central portions of the region. Mesquite prairies cover the greater portion of the western side of the area from Bremond southward. Several large creeks traverse the country underlaid by these deposits, having generally broad, shallow bottoms, with few or no exposures show- ing the deeper or underlying deposits. The Brazos river crosses this region in a general course from north- west to southeast, and in many places the banks form steep, almost pre- cipitous, bluffs. In these the structure and general sequence of the beds forming the lignitic group can best be seen and studied. Beginning at the south side of the field, the highest beds seen are those exposed at the base of the section shown near Bee shoals. The next exposure of any value is that at Calvert Bluff, on the Jesse Webb league. At this place the bank of the river forms a bluff extending along the east side for 700 or 800 yards, and shows a section of: Le Brown: loamy “Clayices 2a 2 ote ee eee oe ae ee ee ee eee 4 feet. 2, Light brown Sand’... cane oes wie elmer es ates ae oe ecm, eens 7 JeCians 3. Brown sand and oravel. tea. sess ee ee are ee eee 114 feet. A. Gray sander ces sh tes vont | awe eae. Sea eae eae 0 to 3 feet. Boe Brown Coal, siactises hia sae Goth. eet eee bee eee eee 12 feet. 6. , Dark .bive Clay isd. oh cece be See ae S Ronee eee are 3 feet. As BLOW DCO AL qo cia vis ie otek Bae sett ates ai bos betcbake tres nerfs a Gree eee eee 3 feet. 8. Dark bite Clay scincwidaws &: Pa ston bp ieee sau otter es a eee 6 feet. 9.” BrOWD ‘COaL 7. 26-4's sia os ails Lew akece hie aueeine Silks alate epee ete eed 3 to 4 feet. 10, "Dark crayish blue Sand sh wh te. ates oe cote hoes ten ea eee Mee eat 15 feet. “Il. Thin stratum of calcareousrsandstone:. c.. Acie), ee ee Re 1g foot. 12. Dark cray-sand similar to NO wiGsi sink. toi pum ae ee ae 2 feet. 13. 2Brown coal. poor-qualiby =. 3 oe ee eee 2 to 6 inches. 14. “Dark*yray sand,’ similarite NO;i0, ok wen + ae ee ee 8 feet. 15: Gray Calcareous'sandstonen. .o..te. 0 c.56 = sk ries ae et eae 1 foot. 16. Dark bluish gray sand, with quantities of iron pyrites ...... 8 feet. 17. Boulders of clay ironstone and gray calcareous sandstones, with nodules of iron and thin seams of ferruginous sand- stones with fossil leaves .......... Weis Lek see pap ek 2 feet. 18. Gray sandstone, weathered and eroded into an irregular cap- PINS COVETINS IN O04 Oe. To ote tartans Ge arin el 2 ee err 116 feet. 19. Laminated bluish gray sand to water at Herndon shoals..... 2 feet. This section extends to within a mile of the upper portion of the next section at Bee shoals, and between the two a section on the west or Milam county side of the river shows: LPePESTOW TL YROUE Se oe cieeatio on ah 8 2 a he ce Say a eek ee ates Fa tae ee ne eee ee 1 foot. MOY CLOW BANC Y OLAV ais ie ils» BU'Wic ick Wa oa Geel dhe tes teste Lee RTE ters ie 12 feet. 3. Pale blue sandy clay, with limy concretions.................-.-.06. 8 feet. 4 SABE OW DACOR sas pele ris o0s.) 5 oa orm 0. wie w vie aueceyhinra eee ob Mee epee eo ciao 3 feet. Bae DOU LO Ge eee ieee aca isc Salo So. 90's bien ce ee Br is At PEE SEO 1 foot ROBERTSON COUNTY, 71 ERIC CLA e AN We A ag a ls Oo ee op eh en eh i EO 2 feet. 7. Brown coal at foot of Bee shoals, extending 20 feet into the river... 4 feet. This No. 7 is apparently the same as the thin seam of lignite, No. 5 of of the Bee shoals section, as all the lignites in this region show a tendency to thicken towards the south. Section at Bee shoals, close to Black’s bridge across the Brazos river, on the Calvert and Cameron road: PPSEONVIGIORNE lA a ect isa ck ek s SRP SRO ae IO eae 10 feet. BI GTAVOL) nates ace Bee Re Re ecco Gace a WS REO Hee Hea oho wl ee 1 foot. SMC C SP Vem eeil CREE ets ear ceyerhe Mee SPE in of scai da wel een ark nas ee oes 5 feet. 4, Black or dark blue clay, jointed and broken into cuboidal POC Grate archers nteee eee ere ee ad a Aer y wake Gruen ae ds VO 1 foot. 5. Broken seams of brown coal, running out 300 feet from foot CGO Le porate he OCR ore nan als Sats as cake wan ain naeta de we ees 6 inches. em sae ke Clay. SUINAT COUNO. 44, 2ou oc cuiee Cues <5 caaws Seen Sa ee 5 feet. 7. Pavement of sandstone, brown on outside and dark bluish Ea VeOl IN Sil Gatch ates ay Paes Sere an UN ee eee wise ce 114 to 6 feet. 8. Clay similar to No. 4 to water, running 100 feet up the river 4 feet. 9. Thin stratum of gray calcareous sandstone................ 4 to 6 inches. 10. Gray sand, laminated, and containing thin layers of dark SL Vrs eee ete ee oor Pe Ee Melb ais es VOL UE AN ens 10 feet. 11. Bed of rounded, water-worn boulders, containing streaks of PAULL C titre teas po er eae tee we dial eoneecaetd Weil ea ets 1 foot. Pear ae enc ew losl. DMTibCSiewe a: ctv srqs Ae fk a el mk caiman tle ole Guale 0 to 5 feet. These shoals are about 400 feet long, and the beds dip southeast at an angle of 1 to 3 degrees. Half a mile further north the river crosses another series of shoals known as Cannon Ball shoals. At this place the bluff overlooking the river shows a series of gray sands, in beds from 5 to 15 feet in thickness, and interstratified with thin seams of calcareous sandstones, from six inches to one foot thick. Going east from the river, such sections as can be obtained from cut- tings and well borings show practically the same succession of beds as are exposed in the bluffs along the river. A well bored on the E. D. Peters plantation, five miles southwest of Calvert, and between the two rivers, shows the following section: Memaray ich UIOW!l SOll, SUDSOLL. «cna ycew erties Teens ents Coss ds Opt 10 feet. PLOW SAN Sea elctd feat a Vid'ols du Ser AT One Pte ae aia the ote tela he ate date 10 feet. MCR VAN ENG. OS ai ru! Sea a ote ante cctats ieee aed ee eRe he ake otal e Sa 2aeA 22 feet. Peers tUisly OTAY SHOON, «is aisns's sc ain ee «fia nise eee ted cities OE AS VO Hei sts 's 4 feet. PEST ALVU IT COSTS cele bo ccc cn doce a Oa are ta OU EMER RM es «colds ao es 5 feet. PEPENOSTCOUS SANUSLOILOM, nue oa cin ee tree ee ee ce Cenk ee ee a 1 foot Peer He COR LS 6552s Lt ke SOR ae cea eens Gee Sa Ok 8 a 4 feet. 8. Bluish gray sand, and seams of calcareous sandstone and clay, the sandstones in the strata of about 10 feet. tO. gic e cet eee ein 99 feet. SPE CRNUASCOCT S68) 202225 bo 2 ej Clee ek Re OE Bo 83.5 ba oo eee ee we 4 feet. 72 GEOLOGICAL SURVEY OF TEXAS. 10) 7Same BS NOMS 2 rica Swe eo aac ae lcs Ma ah te deca ey ica ee ee a ee 61 feet. 1h. Brown Coal he i ore ah ore, eee eee Ae eee ee 18 feet. 12S SAIN BS IN Os 6 hee nos sk ccs eee. copes te ceette te tare ole eek ea eee ena 50 feet. Another well bored at Gibson’s gin, near Calvert, shows a section of: 1. ‘Surface soil and-oray and brown sali, wou cut eae enor cetera 25 feet. 2. Alternate strata of blue clay and calcareous sandstone.......... 42 feet. SU DEOWD Oa]. 200. oa lie oe Uae OR aise ees Ce ate Smee he te Sea ee Re 2 feet. 4. Bluish gray sand, blue clays and calcareous sandstones......... 46 feet. 5. BIO WN Coal. 250 he ea stce c sae le sie ceees oelabcns amma ee Nahas os rie ean 116 feet. 6. DIUISICTAy SANG (\.Gi7 . a witalala iin 4 Salem eatin U lely Seeker ahs ae ee 2316 feet. 1 STO WH ICOBIO 5 oe or sele ea ies tiene ten ae el Oe ae 5 feet. S. blue sands an dieandstonesinw eqn: steer wer uah eee in eee ee 55 feet. 9. Brown coals to. ho eae, oe a es ey ek ee ee See 2 feet. Os 46d Clay sien aoe) 5 esc ciehenrenie aia oe nae Richens eeaiaa as fete 8 feet. 11. Bluish gray calcerous sandstones and blue clay................. 22. feet, 12. Brow COal sho'irt.ce ea teem ate lee oes ease Ve rete re eee a Cen, TB." JBL SAD S ne ek a ra ed eral nee Ca AR Ne ae moe eee a ee 76 feet. 1453S BPO Wn COA! F6 leon ke hm irte ait ietaiabee ghee fe ete man RR oe ee 10 feet. 15. Blue sand, with thin seams of calcareous sandstone............. 265 ~— feet. Four miles north of Calvert, at Mr. W. Talbot’s house, a well shows a section of: 1, Dark ‘gray sandy ‘sorl"andsupeoil. fe st ek i ee eee 216 feet. 2) (Garay jOlmtclay, SFite cn cag fale Cae Ponte oe nal gk ee ee ee eee eee 10” “feet. D MaPAY Sanu in weg uate CnmGhaay Be Sead. ae ae eee ie eee, Seen ne 2 feet. A, WOME Clay Bel BAN os Ge wore a a epee tels oe eno es ke a ee S7 Tieet. 5; Brown sand, qwith nodules of iron. .occe 1,6 o ke eee ee ee 10‘ feet. 6s, Nodular Tromore iis te 2. Se rics i Oy ee eee 4 feet. At Jericho church, about one and a half miles southwest of this place, a well 80 feet deep passes through blue sand with a thin seam of brown coal near the bottom. On Beck’s prairie, six miles north of Calvert, a section shown in a small creek gives: Le cGTay £andy SOL. eo ate ws eG au tas wa eee ae ee Ceti ee *. Mec due dina meals caer 1 foot. De eVLOLELON: GANG hes. gous eoy bE os able we ees o Bee ee ee ee eee 4 feet. FAB AIG OLIFE BAG obr cae lh, HOG ic eek ote eee he ee a ate ce ee arte Rc He nae eee 2 feet On this prairie wells bored to the depth of 75 to 80 feet pass through three seams or beds of brown coal, and a section on Wilson’s creek, near the center of the William Fullerton league, shows: 1. Brownish gray sand, with gravel and nodules of ferruginous sandstone, seen on hill near Mr. Wilson's house................ 50 feet. DME ELITR BRATLULY (CLAVE, cs aye ete ws sists sae % 5-cae ae Sus Sees ee eee ee 4 feet. SSIES an Ta hg ee ens cl Sc. oni x dpm bb, 2he) Sea & oe allo ae le Eee a ee eres 4 to 6 feet. 4 arkiordy mana Lor clayey Sand «.,..4s sm s.s,0's era ged dele eee aia 6 to 7 feet. Bs SP STO MICO Rae eine le ste sis 86 =. 5 wie asd Sin arcs Cuctee Re eee a ee ene Se 3 feet. ROBERTSON COUNTY. 73 In the Headville region the lignite deposits come close to the surface, and are exposed in many of the small creeks and washouts. At Franklin a well 1200 feet deep shows a section of: Uo ALAS O RY ie Sle Fa ted il Ri Atel He eM Ae aba eh le ek nh ga 72 feet. 2. Blue sandy clay and sandstones, interstratified..................6. 40 feet. 8. Gray sand and sandstones, interstratified...... 0.0.0 cece eee eee 101 feet. PRTC LG Reale We ELIE WALGI Wet an cum cetaceans rites are cers weg oie sete wane 2 feet. 5. Blue sands and sandstones, interstratified, sandstone strata about 2 feet thick, but not regular, and only occurring at wide intervals.. 855 feet. creeds Muicsatitne WILDE WALOLS voc. urate 3 easiest siete sims ew es oh ne aes ee 1 foot. LYALL CRE ALINC RS cle rete te eet emer ee en yee ries wale han acl eraie aie wes tee 137 feet. MARINE BEDS. Lying to the southward, and succeeding the lignitic sands and clays of the last division, there is an extensive series of brown, yellow, green, and dark clays, sands, and marls. These constitute the division known as the Marine Eocene beds, and are a continuation of the great series of similar beds which pass from the east through Cherokee, Houston, and Leon counties, and extend across the Brazos river into Burleson and other counties lying west of Robertson, with a southern extension into Brazos county. They cover an area of approximately 450 square miles, and occupy the whole of the southern half of the county. The southern border of the lignite group already described forms the northern border of the marine series. The country occupied by the marine beds is broken and hilly, and very generally heavily timbered with blackjack, post oak, other oaks, and hickory, except in the southeastern portion, where extensive tracts of prairie and rolling country appear. Few creeks pass through the region, and these have steep-sided channels with narrow bottoms. The general sequence and texture of the beds can best be seen in the following sections, extending from the base to the top of the series, as far as exposed in Robertson county. A section at the International Railway bridge across the Brazos river shows: 1. Yellow sandy clay, with nodules of lime....................... 20 feet. 2. Brown sandstone, interstratified with brown sand.............. 4 to 6 feet. 3. Dark green, almost black, micaceous unfossiliferous sand....... 5 feet. feintnly laminated) darkeorcerm mands cc] atin Saks, si onl ty 2 5.9 oo 6 feet. 5. Irregular belt of ferruginous sandstone......... re UM 9) 2 etch lg to 1 foot. 6G.) Dark: green, almost black, sand, to water... 2. 020. ate 3 feet. On the south side of Muddy creek a ridge of altered glauconitic sand- stone, containing nodules of iron ore, extends from near the Houston and Texas Central Railway westward for over half a mile, and ends in a 74 GEOLOGICAL SURVEY OF TEXAS. bluff about 50 feet high. It is nonfossiliferous so far as known. The next exposure occurs on Mineral creek, about four miles north of Frank- lin, where the section shows: ly (Orig BUrtace wand. . cs. ash ona ee ete Leis wide Et ies Foes c ceeeheitees 3. feet. 2, Dark gray sand and sandy clay, with gravel. ..............s0s0,+: 216 feet. See TAY SAN FCs Wr eioesin wars aot Sask toto aban ca anak a) ee re 2 sfeets 4. Brown sandstone, containing casts of fossils................eeeeees 1 foot. 5. Thinly stratified or interlaminated blue and red sand and clay..... 1 foot. These sections occur at the base of the series, and with the exception of the thin bed at Mineral creek, are unfossiliferous. Throughout the southern portion of the area the sections show a series of altered and unaltered greensands, sandy clays and sands, all highly fossiliferous. In the southwestern portion of the area the western con- tinuation of these beds is shown at Moseley’s ferry, and six miles north, at Collier’s ferry, a bluff on the west or Burleson county side of the Brazos river shows: 1.-:Brown sand’ i542 8 «pod boas tek kes Oh ee eee eer eee 10 feet. 2.\Indurated brown altered Preensancd. ..13+seee ee eee 8 inches. 3. Brownish green altered greensand, containing numerous Fossils 2 i kere et Ee a Bice © cine ke ee ee 4to 6 feet. 4. 4Grayish greensand,qwith £0ssiis. fe ees tae one Deere ee 10 to 15 feet. 5. Dark blue Jaminated fossiliferous clay .......:......0.-+.. 6 to 8 feet. 6. Brown sCOal iD TiVOr sgn spre iin oe 4 ole Ra ee oe ce ee 4 feet. This bluff is nearly 400 yards in length and over 30 feet high, and the bed dips slightly toward the southeast. The fossils occurring in these beds belong mostly to the families of Pecten and Ostrea. Six miles east, in the neighborhood of Benchley, the sections shown along the various creeks all show exposures of fossiliferous greensands, and at Sutton, four miles north, a cutting on the Houston and Texas Central Railway shows a section of: 1. Brown sand and eravel iyi. vc fukn s ye tee a | ee eee on ee ee eee 2 feet. 2.) Altered-fossiliferous sandstone.tc 22k se. ole is he ee ee 8 inches. 5. OSsilerous STEENSAND 4.2 7s ae sf She ooo sew ne re aie has ee ee Near the east side of the Robert Henry league, at the ‘‘Old Factory place,’’ a section on Pin Oak creek shows: 17a broken SerrucinOUs Maverial.! ... ¢ soos. de oman He cen eile abe eee 1 foot. SeeVieloO wan DYOWIM SAUCY CIAY & .', :\. 5 ond utes) oink 4 eee eae 4 feet. 3. Brown altered greensand, containing oysters and other fossils, PAROSELY STOR OM ca w1e his. o-s cis o's syle aon a elB ae ate Gieiee UN ee 10 inches. 4, Brown sand, with casts of fossils, to creek .................0.... 10 feet. Near the head of Campbell’s creek, on the Stephen Gafford and James Dunn leagues, the western extension of the Wheelock prairie becomes ROBERTSON COUNTY. 15 rolling and broken. This area presents a series of laminated sands and clays, with occasional beds of fossiliferous sandstone. A section of this prairie shows: : Pee CRICHTON eer re Pe GN ene, sa Sate who ou 88k ok Coke ew en es 1 to 4 feet. mes COWL aati Ch es VOELID: DIENT WS ULEULIC BY ott rotated olka Cet ole Aa) ola ahs Ba ure 4.008 2 to 6 feet. 3. Brown ferruginous sandstone, with casts of fossils.............. 2 feet. Near Dunn’s ranch a section of Campbell’s creek shows: ree Ee tO Ke UL Un er mee ah rata SE core eicaik Slee s 4 ares ga v8 bro 2 to 4 feet. UU ESTO em tT 0) SU Latent EOS la rn Bly lesan: oak se nlate osha 248 4 to 8 feet. 3. Fossiliferous sandstone, containing oysters and Cardita plani- ETE R 1 Wa Dip legs 0, Sah DIE, OO Ai ce os OR A are RA ar 1 foot. Rep UTOWwiie ios tN rer Os Salter, stirs Nace vid 2 diva. o'hiy'y o's Fae qle GA we wie 1 to 3 feet. We eee A abode GSS MIOLOUS. ClAY ses... Fe bx Oe cialeti dels oi! 08d vin oe 2 feet. 6. Indurated greensand, with corals and Cardita planicosta V.am., SHUN LORE) Leer et agi ie aad x tart ilee Wk to 47 Giew hehe 4 Bib 6 1 foot. Men} OrslirerOusriaminatod DING CIA Vice 2.65 \o .degee se Jon cess does oe oe 10 feet. 8. Alternate strata of yellowish sand and blue clay, the clay strata 6 inches, and sand from 4 to 8 inches thick ..........0..e00e00s- 4 feet. Sees PCa Pe YL VS eet ra tetera ae Wares ee oad a es See cod Ag ony 84.5 ch 8. ea bales 1¥ feet. Half a mile farther west a section on the same creek shows: Peer tL ACG y OLlO WIN DEO WI SAUL) oul yd nae seis os aoe he denas wes 10 feet. Semen TOV 1h SALCEMVILUIGLO BSL IC hr malware the «see Modes Poe ds cule Tek oes 2 feet. 3. Ferruginous sandstone, with fossils ...........50... cc eee eeees 1¢ to 1] foot. 4> HOesHilerous Sreensan Ux VISIDIE fig 6 8) pn ce oye we vin acide Pale aw be 4 feet. In the Wheelock region the brown prairie sands and loams cover the greater portion of the area. On the top of some of the higher ridges or knolls east of Cedar creek grayish brown sand, with occasional patches of a soft brown conglomerate, occurs in considerable quantities. The section in this portion of the prairie shows: iy Aka Ls. DLO Wilks SOL irs ke on eteuet aes oc akea Scare boty wees de as etc ah 1 to 5 feet. 2. Brown sand, with Spirorbis leptostoma, Swain, and casts of oo FORATIA ANU SECTORS OL LLINGie ce. 3 ae Ce cna ee a et cnc ona eee 2to 6 feet. . Blue laminated clay, irregularly deposited in pockets, from.. 1 to 10 feet. . Thin stratum of fossiliferous sandstone, containing great numbers of Plicatula filamentosa, Conrad. ................ 6 to 10 inches. PERE? SAIN oy, grat tao we 6 tn wea wataten fare ene nane a ee eriahads aes § lto 4 feet. Along Cedar creek, from the Madisonville road bridge southward, ex- posures of brown and green fossiliferous sands occur for a considerable distance. Half a mile south of the bridge a section shows: em COD PEO mIesOll Of OVETIOW JANG «6k ese suieme iene ants ws oe wales wee 5 to 15 feet. Brown altered greensand, containing numerous fossils ........ 4 feet. Peccroinous fossiliferous sandstone 22.e. Mee coca sos sis vse 1 foot. Dark grayish green fossiliferous Sand 2.2.2 yc. ec cee ee eee ee eee 4 feet. 76 GEOLOGICAL SURVEY OF TEXAS. Going down the creek, another section, 100 yards farther south, shows: 1, .Brown Ban 20 Ske rs ih ak in ke og Reals, nde Paes ea ects ee en ee 5 feet. 2, Laminated biue-and pink Glayse. me eee ee oe ee 4 to 6 feet. 3; Wark green fossiliférous sand +. sk ot se. eee eae te see keke ie 4 feet. Five hundred yards further south another section on the same creek shows: 1,.° Brown sand, pottom fand 2,0 fos oe we tee ee ee et ser ate eee eee 10 feet. . 2. Dark brown and purple brown laminated sand and clay, with fossils in the Band, to creeks bet sc, ce ce eee oe ee eee 2 feet. Throughout this region fossils occur in the different wells bored or dug to the depth of 30 to 50 feet. ECONOMIC GEOLOGY. SOILS. The soils in Robertson county may all be considered as fit for cultiva- tion, although poor in many portions. They belong to the two great divisions—the alluvial or sedimentary, and the residuary or sedentary, of which the alluvial, although ranking only as second in point of extent, is the more important—and may be subdivided as follows: First.—Alluvial, constituting the soils found throughout the Brazos river valley, on the western side of the county, and the bottom lands of the Navasota river, on the east, and connected with several of the larger creeks. These lands are estimated by Loughridge to include about one-fourth of all the soils under cultivation in the county. They lie principally in the area between the two Brazos rivers. The soil is an alluvial loam from two to ten feet deep, varying from a gray sandy to a red and black waxey, and the subsoil is frequently sandy and sometimes clayey, of a red brown color, and extends to a depth of over 30 feet, where it rests upon a bed of white rounded pebbles of quartz and other gravel. Where these soils are sandy the tillage is easy, but when the soil is clayey or waxey, difficult in wet seasons. They are well drained and equally well adapted to cotton and corn. These soils belong to the Brazos river lands, which are considered the best and most valuable in the State. An analysis from Dr. McLendon’s farm shows: KS SS greensands, oe ° al oO oS i=) ° 2 S ~ o a ~ teal ° Zz Sroparneeest en Be Brown coal. Railroads. Sy hy HRS } --~~- County roads. ee Y eZ (/ y es Yj y Yy j Y SA ft UL Sieg N t, ee Y Mp, YW “Uf WN KK Z —I5w SSN N Z ZG Lf A. SIP ty WSS Tortie MAP OF ROBERTSON COUNTY, ROBERTSON COUNTY. Soil. Paeouinie in NYATOCHIOFIC acid v.66. ce veces vanes 54.06 So SAS Re Ne PRE TS ld i 11 .89—65 .45 Pe Re eee 5 oh 22. Vas Sek 6 dy a cea Ya 0.307 SE eee TEN ls aC on cee wae 44h 4 kang owes 0.60 tT MR RIE) Se a rays vik ol 9 «ind bg mec aw 6% 8.07 WTO TESTO FR 9th 6 Beg TORRE Aa ere ane 0.78 Ore GrI aN SAN CRA SOV ds. eso adhess suv dsaeae ts 0.10 POUR ORTECACLON a lala Sere nl ay Sets sony eh d o4 § ve ea hs 3.47 ARS AWE ie GUN BO So Se a 5.56 CD co SUVA STS (PGE GO eV ca NRE aI ae a 0.088 PEI DAE Ts MCE oa ane Oh Dual Rye eee rn he trace GEOG Ol Pam eee ar Sei Cate de Ltn ke ca alg Ws 7.26 ELGAR Mea rN eae he see cele ks «5's 1.63 iN VisRe NEP Te AR POL er se a Se ire aly « Web 9) dle alee bas 6.04 99.355 A mechanical analysis shows the physical condition to be: a Ol Fixed. Volatile. MUO MALUM SL COR ME Tene Peer ulna se ae Se eu ooh ego Seeks CORE res iss Tate Weta SE i AGRE ca A ioe er 2.88 0.56 MERIT RIOR a ea re eR he rey a 15.68 1.69 PRIRCe Seu ID OhNe Chdatal bay Det Te oh gs Seo Wy wal laity 46.38 2.38 PRT R ta EMR Meu eM eM aia a Us cca Age ML sgl @ Wh he 20.07 . 10.36 85.01 14.99 WY --— + 100 Geta TOMI ALCL a ead ch lc Wea ewe. Vialain't's & alace 56.8 per cent. Analyses by Dr. W. H. Melville. Second.—Upland soils. 17 Subsoil. 51.83 12 .18—63 .96 .278 BY .67 .20 .66 04 13 .082 trace 7.74 1.29 6.27 ODO WOoOr tO OS 100.05 7——Subsoil—— Fixed. Volatile. 0.18 0.13 25.20 1.58 16.08 5.64 43 .16 8.03 84.62 15.38 We = 100 62.2 per cent. These cover the greater portion of the county, and are chiefly of a grayish sandy nature in the northern part, except in the prairie regions. overly a red or yellowish clay subsoil. soil, except near the timber, where they become sandy. They are from five to twelve inches in depth, and The prairies have a stiff loamy These soils rapidly deteriorate under prolonged cultivation, and are said to lose about one-fifth of their productive power in ten years. are early and well drained in places, and easily cultivated. gives the following composition :* They An analysis Soil Subsoil. Peeiniia im hydrochloric acid). i a teteweanetiagsa seas vs 89.23 90.20 MMMRETHIGETICA rhe ar woh, ails atin Ldale's G Seldle alga ated Sears cies elu oc 3.81 3.12 EMEMIETNELG ACLS Fs Wo sae he maldcs dre) Ode geen st siomtmmnead tac «+ 0.006 0.008 CMT Ga 2 5°5°s Cuca teas Ge Gam ees cee ea do wee a ad. 0.032 0.044 tp 8 10 STS ene re meee ne i eg: FOR ede) ene 0.232 0.20 * William Fullerton league. *8—Geol, 78 GEOLOGICAL SURVEY OF TEXAS. Soil. Subsoil. t Bi tvsl; OAR ennai ALAA RGre Cree SPem ah hh mie tae Mes BA AD 1g 0.20 0.24 Carbonic’ acide vr se sae ks eG RGLheeaaeen > LUE EER ORE ER ES 0.11 0.09 AE) ee eee SL Ares on £4 SAA es 0.12 0.05 Ferric -OX100 yi Wis ie eens ch CREE RERTEO CENTRE EEO EY 0.98 Le PA TUTTI a so Rie rts Nk scene ht eats ROE ea noes Pile ste ee a eae eee i Deere 2.27 Manganese OxXidG hw i. \s cies stetabe se etetarstoetabote a vebatsis le hishers fe tabel oes 0.04 0.19 SUL MU LEG ACTOS Ai Reine io gin creas aRNa setae teRcte she Mei Re tee iphone nen tee te trace trace FLUTE eG es eat ee es Re cE PASH LENSER ES RRR LR a ey ie se 1.67 0.73 Yes a OO OL MAR RM Ri Te ke MCA! Rn Ay ae ihe yf 1.74 100.03 100.03 Their physical condition is shown by the following mechanical analysis: ————_Soil-——_ ———Subsoil-—— Fixed. Volatile. Fixed. Volatile. Stones and ticks vias ou & goats a cit cone ee tee Auoo 0.26 2.19 0.26 ChOATSO ISAIVG cecal ess Lee i oret te nee an 10.46 0.32 24.58 0.16 Medium Sandee: Mee oes ee tee cee ye ee ee 48 .54 0.52 48 .84. 0.50 AIT.0 GIO GL Cele Pe Ne tae tee Baten aber 20.35 0.85 19.11 0.60 BMG TO BOUL cee VB a Se ek Ora Sa ee vee mee 15.51 1.83 3.00 0.76 96 .22 aS ies: 97.72 2.28 eT W-——~ -- — YY 100 100 Capacity Or waters dc cs wee teu ss ook eerneee 39.9 per cent. 35.8 per cent. Analyses by Dr. W. H. Melville. The soils of the higher grounds in the central areas are light gray sand, and in many places little else than a deep white sand, rendering many of the roads through the region almost impassable at many portions of the year. They are usually covered with a heavy growth of sand oak, post oak, and hickory, but may be considered as almost worthless for the pur- poses of cultivation. In the southern and southeastern portions of the county the extensive prairies are covered with a dark brown or black soil, changing to yellowish brown color in places, very irregular in depth, and in many places a brown ferruginous sandstone comes up to within a few inches of the sur- face. Where of sufficient depth for tillage this soil is considered good. This area is not much under cultivation, and is used chiefly for stock purposes. BUILDING STONES. The building stones of Robertson county are wholly of brown sand- stone, and occur in many locations along the ridges extending across the county from the Houston and Texas Central Railway eastward. They are rather coarse-grained, and contain frequent streaks or pockets of coarse sand or fine gravel in the form of a conglomerate. ROBERTSON COUNTY. 79 The sandstones found along the top of the ridge on the Denver Jones headright form a bed from two to four feet in thickness, and have been quarried for railway purposes, having been used as piers and abutments of bridges on the line of the Houston and Texas Central Railway. Near Hearne, another deposit of the same grade of sandstone has been quarried for building purposes. This deposit is small, and covers the top of several small rounded hills along the east side of the town. In the neighborhood of Franklin the hills near the town and surround- ing Racetrack prairie contain soft brown sandstones, which may be utilized for building purposes. They also occur to the west of the town, and at several other places in the central portion of the county. CLAYS. Throughout the greater portion of Robertson county good brick clays or earths are plentiful, but with the exception of one yard at Calvert and two at Hearne, no permanent brick making is carried on, and even the yard at Calvert has been idle for some time. In only one of the yards _at Hearne is work carried on continuously and systematically. This yard, that of Mr. Robb, employs about twenty men during the busy season, and during 1892 the total output was 1,250,000, at a value of $12,500. The bricks are hand-made and dried under cover. In burn- ing, bituminous coal is chiefly used. The smaller Elliot yard turned out 500,000. In the northeastern portion of the county deposits of clay suitable for the manufacture of the finer grades of earthenware exist. Clays closely approximating the Kosse fire clays also exist in this region. These clays were examined by Prof. Streeruwitz a number of years ago and consid- ered a fine grade of fire clay. The extent and locations of these deposits can not as yet be given, but will appear in the report on the clays of the State now in course of preparation. BROWN COAL. The great East Texas brown coal belt extends through Robertson county from the eastern boundary in a west by south or nearly south- westerly direction to the Brazos river, and comprises an area of almost one-third of the entire county. ‘The northern boundary of this lignitic area is co-existent with, and extends across, the northern line of the county, and the southern limit of the field lies along a line extending from the Navasota river westward to Owensville, and then along the northern bank of Muddy creek to the Brazos river, near the mouth of Little river, in Milam county. This region embraces Tidwell, Beck, 80 GEOLOGICAL SURVEY OF TEXAS. Head, Heard, and Bald, together with a series of other smaller prairies lying across the center and in the northern portion of the county. Throughout the whole of this area, with perhaps a portion of the ex- treme northwestern corner of the county, brown coal occurs in greater or less quantities and at various depths, embracing eleven seams lying at depths ranging from 15 to 320 feet, and ranging in thickness from 13 to 21 feet, of which six seams contain enough to allow them to be worked. These workable deposits fall into two divisions of three seams each, dif- fering chiefly on account of the depth and accessibility. The first divi- sion comprises the following: Thickness Location, infeet, Of Prown coal, optainable, Ti Calvestebliitiy.caet esis & cone alts Week Chee retiee t 15 12 Stripping. 2 Peters {planta ti ON vies naa ssa ane 46 5 Shaft. Bp EOC PIATIGs Wes | wikvc mus Me wheels ucees Fhe Mie AML 62 7 Shaft. These brown coals are all available at the localities given. No. 1 can also be reached without difficulty at Dr. George McLendon’s farm and other points on the Little Brazos river. In the second division, although three localities are given, it is more than probable that two of them (Nos. 1 and 2) belong to the same seam. Depth, Thickness How Location. of brown coal, obtain- in feet. in feet. able. Lo tJesse VW CbDeaguen ica atl oe eae cen tae tN oreE 220 21 Shaft. Dat Ws dds Oe OLELS + PIANTALION 00. cigs ase ie os ae Bynes 240 18 Shaft. 3. Gibson's wellat Calvert. fy ecco ei Gates eee 320 10 Shaft. Mines operating these seams will probably all require pumping to keep them dry, and can not be worked profitably under the present condition of the trade. In the northwestern portion of the county the lignitic beds are repre- sented merely by thin seams of lignitic clay and lamine of lignite of no value whatever. The best exposures of brown coal are seen on the Brazos river at Cal- vert Bluff, where three seams of 12 feet, 3 feet, and 3 feet, aggregating 18 feet, are exposed near the center of the bluff. The deposits shown here continue for a distance of nearly a mile up and down the river. Several exposures occur in the banks of the Little Brazos, on the Joseph and Jesse Webb leagues. In this region the most important open- ing is that on Dr. George McLendon’s farm, where the brown coal shows a thickness of 8 feet overlaid by 23 feet of brown and gray sand and sandstones. A similar exposure also occurs a short distance down the same river. Near the north side of the John Fisher headright a shaft 60 feet deep cuts a brown coal deposit six feet in thickness, and on Wilson creek, near ROBERTSON COUNTY. 81 the center of the William Fullerton league, another shaft passed through three seams of brown coal at 55, 70, and 80 feet. In this region the brown coal is also exposed in the bank of the creek. In the prairie regions brown coal appears near the surface at various lo- calities, and is exposed in several of the creeks and washouts. At Head- ville, on the C. C. Seal headright, the exposed brown coal is from 4 to 6 feet thick, and the deposit on Wilson creek is from 4 to 6 feet. Asa general rule, however, the surface exposures are thin and of no economic value. Thus the exposure on the Captain Orvis farm, on the southwest corner of the George Robertson league, is not more than two feet of broken crumbly lignite. Another outcrop of a similar nature occurs in a small creek near the center of the Joseph Fisher league. The lignite at this locality is broken and crumbly at the south end, or toward the head of the creek, but as the bed extends northward it becomes dark brown in color and assumes a woody or peaty structure, having the character- istic odor of the latter when freshly broken. ‘This lignite also contains numerous fragments of leaves. The heavier deposits found throughout the prairie regions all lie at depths of 45 feet and over. Brown coal also occurs in the neighborhood of Owensville, where it is overlaid by a red sandstone. At Hearne the brown coal is found ata depth of 408 feet, while in the neighborhood of Wheelock, and at several localities between that place and Franklin, wells 50 to 60 feet deep fre- quently cut through beds. In the valley of the Brazos, and in the region lying between the two rivers, brown coal occurs in well borings generally at depths of 30 to 400 feet. This is, however, of a poor quality and in no great quantity. Desultory mining and prospecting work have been carried on at various times for a number of years. A shaft 65 feet deep was dug several years ago about three miles north of Calvert, on Mr. John Walker’s land. An- other shaft, over 100 feet in depth, was dug on Beck’s prairie by the Texas Coal Company, and several smaller shafts have also been made in different portions of the county by several parties. Brown coal has been mined and shipped at different times from Calvert Bluff, and a quantity estimated at 300 tons has been obtained from a sur- face opening at Dr. George McLendon’s place on the Little Brazos. | The neglect or abandonment of these operations are not due to any peculiar defect within the material itself, nor to any serious obstacle in the way of mining, as the workable beds show as good facilities as many now mined, but is due altogether to a lack of facilities for transportation. The beds lie mostly at too great distances from the railways traversing the county, and the cost of teaming is much greater than the prices ob- tainable for this class of fuel will stand. 82 GEOLOGICAL SURVEY OF TEXAS. TIMBER. Robertson county is fairly well timbered. Of the 869 square miles, comprising the total area of the county, probably 650, or nearly four- fifths of the whole, are more or less covered with timber of fairly good growth. Throughout the higher lands, post oak, red oak, blackjack oak, hickory, and elm form the prevailing timber, and the bottom lands, where not in cultivation, are covered with pin oak, walnut, pecan, cedar, ash, and cottonwood, with several varieties of smaller trees. Along the western side of the county a great area is covered with mesquite brush. WATER SUPPLY. Robertson county may be considered as fairly well watered. The Navasota river, with its large tributaries, such as Duck and Big Cedar creeks, on the east and south, and the Brazos and Little Brazos rivers, with Walnut, Muddy, Spring, and Campbell’s creeks on the west, con- tain a supply ample for stock and other purposes throughout the whole or a greater portion of the year. ‘The other and smaller streams are usually dry, or exist only in the form of a chain of small pools during the summer or dry months. There are few springs in the county, but water can readily be ob- tained from wells of medium depth almost anywhere. In nearly every locality the water so obtained is of a very fair quality. According to the Census bulletin (No. 1938,) the number of artesian wells in Robertson county in June, 1890, was 120, showing an average depth for shallow wells of 165 feet, and 750 feet for deep wells, or an average of 464 feet. These wells have an average flow of eleven gallons per minute, and the average cost per well was $189 Since that time many more wells have been bored in various portions of the county, in all of which water has been found at various depths, although a number require pumping. . The flowing wells are all confined to the southern portion of the area of the Brazos valley as far east as Hearne and Calvert. Wells bored in that portion of the valley lying north of a line drawn from Calvert west- ward to the Brazos river near Calvert bluff are generally very deep, and in every case require the water to be pumped from 100 to 120 feet. In the Mesquite prairie region, along the eastern side of the Brazos valley, three wells at Hearne bored to a depth of 520, 700, and 720 feet are all flowing wells. Three wells at Calvert obtained water at an aver- age depth of 600 feet, which may also be considered as flowing wells, although the water in two of them does not rise more than a foot or two ROBERTSON COUNTY. 83 above the surface. The well at the water works obtains its supply at a depth of 587 feet, and provides 135,000 gallons daily. Still farther north, at Bremond, a well said to be 1500 feet deep requires pumping. In the eastern portion of the county the only well of which any record has been obtained is a 1208-foot bored well at Franklin, from which the water has to be obtained by pumping from a depth of 80 feet. From all the data at present obtainable there appears to be but slight, if any, chance of artesian water being obtained anywhere outside of the area in the immediate vicinity of the Brazos river and its valley. MINERAL SPRINGS. There are several mineral springs in Robertson county, but those of only two localities are utilized for either commercial purposes or as health or pleasure resorts. Wooten Wells, the more important of the two, is situated about three miles west of Bremond, with which place it is connected by a short line of railway. There are here four springs, or wells, showing the following analyses :* No. 1. No. 2, No. 3. No. 4. CUPOr rer ii GU LOLI GH ad as «oes sv ele chess eas nee 24.34 33.13 35.46 36.36 PT GMBUEOUGOMIC OP a ta. sacle tc Cdedansceetedes Ei Gis ets aca at heer, MER ear ae Pion LO LG Aart et yicls: be a d-arele Sow! diss aes Oe s 0.99 OS irs Sees 13.06 Pee LG Rae etre ate Wo ne oe Rate ae Soe sa Se eek ciewl wae. Wie wees re PANEER INTE Gs Cal ak 8 Te Gi ASS eA San oP 0.54 04 15.05 ) 0.57 PAT UIAT VER TENTL ETON SCLALOM itte W's Wiad hOy vais <8 ¥ creo hork wed KE eee OM aS wide Ale! earoenis Witlee ¢s PU LUMTLIVELIIAY BORO ULORIOUG sic) sil. oe al dalties siaa’e es 1.22 PDO awe, « 3.46 SL eM seri a as So aad, os weet e: Sais Sis! wa Be area tho SS dies VAN OS) My Tee 18.10 MU POMOD EMEC Tale cena ic aan dicta So 4 alent a ol oo) oh Sala eek 13.11 11.38 17.49 22.75 BisIClU a O MIN Gls dcaam cde 2 files de ewe ee etal e 25.21 25.89 27 .10 28.11 Bde ante yrs cask was ees adele d adda cers a4 3.28 BN aie ay, 4.08 pulphuric acic in’ sulphates i466 oe Veale ss 59.67 67 .23 79.25 86.41 © Volatile and organic matter.............008. OSG 2M aghast 12.25 ORANG Se editea aterm iaheraie siiaastiea a washee saree 139,907) 168.11" 186.60). 212,90 At Franklin the wells known as the Overall mineral wells are used commercially chiefly. The analyses of the two wells located here are: *Bulletin No. 32, U.S. Geological Survey. Analysis No.1 by C. F. Chandler, Nos. 2, 3, and 4 by W. M. Mew. 84 GEOLOGICAL SURVEY OF TEXAS. No. 1.* Chloride Of BOCIUMN ss Nita ce en has ele nie eee eines ne teats ina 9.715 SUIPDATS OE BOGIUIMN:, .. atic ese oat tees ciel eee ean 7a. ae Net Nene 7.100 Sulphate-of potassium swe cs wae see ee melee seth a ks are 0.752 Sulphate oLtalaminaic ee eek tes ae eee eee heey ue 1.700 Sulphate of protoxide OL iron ts 7s ipk oe ices Westie licker poe sue @ 75.952 Sulphate Of TiMegacy wows wks. c esl Aue te eae Mitts slats epee ctican roe 20.965 PULP DATATOLINAONORIA 20. Co do Sahl ec etae paltry came etnies a eect es 13.063 SUI PH SCG OF VATION IE. et. wad sch eee im cert Mn even cera tothe aa trace EOE Bh ome tN ha MAREE ANL Ii GE rae te RIA oA te alia ads UM To} 2.041 Organic and volatile matter un tine iy eile ese ans eeu uke 2.450 Lotalbgprans in UsS gallon eae cow eu es. beet 133.738 These waters are acid. * Analyses by Dr. Everhart. IN'Os5 204 8.0538 41.118 2.500 4.898 144.903 37 .095 260 .843 7) 3. BLACK SHOALS. p. 96. 2. MOUTH OF Z LITTLE BRAZOS. p. 53. Water Line. 1. MOSELY’s FERRY. 4, OYSTER BLUFF. 5. SANDSTONE, p. 52. Sec. 1, p. 68. p. 78, ul ra -parq Kuno) a & iy B Aare) Heys oa 4 ; E wpopagnge hi g aa = id oe = a acim B DG ee sia any soled Becca 3 ad g ‘ 8 x r 2 UDI E co Bia h { *Y294) YRO uid ji “a\jyared] Siessiliferous gray sand store . - ey a — “‘BoSuDpaly Ve 2 7, 4 A Zi ~ ne! ca ) i ae) = 2 eee = 2 eo eee | 29 = U10g||2.M If! S i) 2 2 : _ : DQ ee EJ & a 0 op) 5 © ap) os mn : | 3 : Z Bl & _ o) 2 a i z = Zz H z as oe) iS a > z z 2 dp) s$urade wini\2) ; ‘sBurad@ quid] f) ey Ur ISDA é ne 5 4 s Ss £ : x g | B Uy Ws Dobertson @ s on Cretaceous Marl s