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Rae, Colin Campbell Structural relations of the Coalinga oil fields and probable origin of oll 1912 BIBLIOGRAPHIC RECORD TARGET University of California at Berkeley Library Master negative storage number: 03-67.45 (national version of the master negative storage number: CU SN03067.45) GLADIS NUMBER: 184785330H FORMAT : BK AD:991006/FZB LEVEL:b BLT:am DCF:a CSC:d MOD: EL:7 UD:030604 /MAP CP: cau L:eng INT: GPC: BIO: FIC: CON: ARCV: PC:s PD:1912/ REP: CPI: FSi: ILC: IT:0 040 CUScCU } 090 SbDISS.RAE.GEOL 1912 100 1 Rae, Colin Campbell. 245 10 Structural relations of the Coalinga oil fields and probable origin of oil. 260 Scl912. 300 [11, 29 p. ;S$c29 cm. 502 Thesis (B.S. in Geology) --University of California, Berkeley, May, 1912. 610 20 University of California, Berkeley.SbDept. of Geology and Geophysics$SxDissertations. 690 0 Dissertations, AcademicS$xUCBS$xGeologys$Sy1911-1920. Microfilmed by University of California Library Photographic Service, Berkeley, CA FILMED AND PROCESSED BY LIBRARY PHOTOGRAPHIC SERVICE, UNIVERSITY OF CALIFORNIA, BERKELEY, 94720 DATE: 7/03 REDUCTION: 10 X J PM-1 3%2"x4” PHOTOGRAPHIC MICROCOPY TARGET NBS 1010a ANSI/ISO #2 EQUIVALENT 10 =I 2 = kw = uo I= = mao Efi l= * = = Ie le fis pis ey Mh Ve _ 4 " a : BEI SIE SHEE OE nl bd bl lb STRUCTURAL RELATIONS OF THE COALINGA OIL FIELDS All PROBABLE ORIGIN This Thesis is Submitted to the Geology Department of the CALTFORNTA Colin Campbell Rae ’ To Satisfy the Requirements for a Degree Bachelor of Science in the COLLEGE OF MINING. LIBRARY COPY Hay 1912. | I'S OF THE COALINGA OIL FIZLDE PROBABLE AllD ORIGIN OF OIL. 1. INTRODUCTION. The study of the structural relations of the Coalinga 0il Fields and probable origin of oil was under- taken upon the request of certain oil operators in the Coalinga Field, who have been confronted with difficulty in understanding the relation between the fields, and the pro- per point at which to cement off the water. This report does not deal exhaustively with the subject because of lack of data and sufficient time, but the data furnished by many of the oil men have enabled a comparison and study of the Fields which may prove valuable to many operators. During the summers of 1909-1910-1911 the writer was employed in practical well drilling in the vicinity of Coalinga, which developed an interest in the geological cor- relation of the Westside to Eastside Field, and a knowledge of the limitations imposed on the geologist by the difficul- ty of correctly determining a new formation, and by inaccur- acy and carelessness in drilling. The development of the deep territory between the Westside and Eastside Fields has taken place since BULLETIN 398, U.8.G.S., was issued. The wells drilled in the past year have afforded the most valuable data in this paper. The possible origin of oil was suggested by a study of the different California oil fields, and by chemical and geological conditions favoring such an idea. The evidence is very suggestive, though probably not conclusive, end is offered as an idea which seems to be supported by certain correlative facts. STRUCTURAL RELATION OF THE WESTSIDE TO EASTSIDE FIELD. The development of the Coalinga Oil Fields during the past few years has opened up the region between the West- side and Eastside, and allows closer examination and corre- lation of the two fields. This perhaps may explain certain problems of water trouble and drilling, which have caused trouble. The field will be treated from a structural stand- point, disregarding,for the time being, the paleontological problems, about which there are still disagreements, The different formations will be classified under the names given by the United States Geological Survey, except the term Santa largarita shall include the lower portion of the Jacalitos, which name seems unnecessary from close study of paleontology and the strueture. This will be considered more fully later. In selecting a cross section from the Westside to Rastside Field for study, there were several important con- aiderations regarding the location. The principal idea was to have a section at right angles to the supposed strike of the enticline to obtain a correct impression of the structure, and to locate this section along a line having the most ac- curate data. The topographic map of the U. S. G. S. by Ralph Arnold and Robert Anderson, showing locations of wells, and 4. date furnished by the kindness of several Coalinga Operat- ors, especially Mr. R. E. Haseltine, greatly assisted the work. The cross section was selected from a point near #4 of the Ward 0il Corpany and followed this line:- through #9 zrer, below #10 Esperanza, about two hundred feet above Coalinga Aztec, through #2 Empire, three hundred feet below #78 Standard 0il Co., and through #47 California 0il Fields, Ltd., extending beyond to a total length of about five and one-tenth miles. The true bearing was N 51° 46 E. In view of the long extent of the section, and the desire to have the vertical scale as large as possible in comparison to the horizontal, the scale of five hundred feet to the inch horizontal, and two hundred feet to the inch ver tical seemed most justified. Some difficulty was experienced in securing the re quired logs, as certain companies refused complete data, and 2180 in locating the wells and elevatons exactly. The us- ual inaccuracies of the loge and the necessity of projecting most of them upon the section, involved slight errors with no great effect in the geological or practical value of the worl. Certain distinctive features, such as tar and oil sands, sulphur water sands, brown shale, hard sandy beds, or a change from a predominately sand strate to a predominately shale bed, ete., furnish the basis of correlation. It is 5. almost impossible to follow the varicus narrow, alternate beds of shale and sand, due probably to their constant change in character and to the inaccuracies of the logs. For this reason various stratum have been grouped together, because of their similar character. The scheme adopted to show the formations in black and white for printing effect seems to be different from pre- vious methods. The usual shale representation by parallel lines, and sand by dots is used; but the gradual change from shale to sand is shown by alternate parallel lines and dots, the relative space occupied showing the proportions of each. This method was used because of the impracticability of fole lowing out narrow lenses or constantly changing formations with any degree of accuracy. The section shows the structure of the Coalinga Field to be an extensive, gentle sloping syncline, with a 8Sup- plementary, moderate dipping anticline. The crushing effect of the force producing the anticline upon the formations is very well shown on the steep side of the anticline by the thinning of the beds, being made more compact by the pressure. The evidence seems to support the theory that the force pro- ducing folding came from a northeasterly direction. The first important structural feature, which is different than previously judged, is the main anticline. In- stead of having a steep dip to the southwest, the formations are at a similar dip to that of the Kettleman Hills, being about twenty to twenty-five degrees northeast, and thirty- five to forty southwest. This will relieve to a consider- able extent the fears that the formation might be badly brok- en or overturned, thus introducing the possibility of water occurring with the oil. The wells on the dip should be good producers becsuse of the extent of sand pierced, provd- ed the proper care be taken in shutting off water at the pro- per point, This factor will be considered later in explain- ing the structure. The top formation of the section, noted chiefly by dots, consiste of yellow sand, blue and brown shale or adobe, and seems to be a recent deposit, so most likely can be call- ed part of the recent vallsydeposits of the Tulare formation. There seems to be an uncomformity between the Tulare and low- er deposits, as would be naturally expected, being probably detrital from atmospheric agencies and river action and lake deposits. The next formation which is shown on the section as sande and shales, with the former in predominance, is the Etchegoin series, consisting of massive grayish-bdue sandy beds, with blue shale and clay. The material near the top is much finer and softer, grading to hard sand strata, sands, and gravel nearer the base. These beds are noted for their water bearing qualities, and water is found at various horizons. The base seems to be claarly defined by a continuous hard sandy bed with a little blue and brown shale associated with it, The dark shale may have been derived from the disintegration 7. of the formation beneath, which has brown shale in three or four horizons, the upper strata having distinetive beds, such as brown shales, which suddenly stop, appearing to in- dicate an unconformity, since similar beds are continuous in the lower strata. Then near the base of the Etchegoin oc- curs the rich fossil bed or Glycymeris zone. The thick- ness of the REtchegoin is about nine hundred feet on the syn- elinal fold and five hundred and fifty feet on the steep side of the anticline; the difference represents chiefly the great- er compactness of the beds due to foldirg, as deeper wells along the sloping anticline to the southeast have proved a thickening of the formations to the southward. Below the Etchegoin, there is no apparent break in the sandy clays, blue gravels, sand, brown shale, until a zone of hard sand and "shells" is reached, which is known as the Tamiosoma zone, due to the occurrence of fossils of that species in the associated fossil beds. Further study of the Coalinga district in paleontology seems to indicate that the Jacalitos formation cennot be clearly defined, and struc- turel evidence supports this conclusion also, so I will use the term Sante Margarita as a convenient term to include the formations from the Big Blue to the Etchegoin. There are severel hard sand beds more or less persistent in the Santa Margarita, and apt to confuse one with the real base of the formation, which ie only determined by the presence of the familiar Big Blue. 8. The effect of hard strata between softer strata on topography is very well illustrated by this gection, the hard beds of the base of the Etchegoin and middle of Santa Margarita determing the slope and ridges of the higher land on the anticline. The very prominent hard sandstone and gravel lens in the center of the Santa Margarita may have caus- ed the separation of this formation into two parts, as this bed is prominent in the Eastside Field, but pinches out and becomes less hard to the southwest, The occurrence of wood in this zone indicates that a slight intervel might have oc- curred in certain parts of the field, due to slight local movements, but the interval was not extensive enough to al- low a definite grouping. Water occurs at a few horizons in the Santa Margarita, usually in the beds associated with the basal sandstones, which appear to be uncomformable with the underlying Big Blue. The Sante Margarita is about eight hundred feet thick on the synelinal fold, but is only four hundred and fifty feet thick on the steep part of the anticline, The crushing effect is proportional,within reasonable limits, to the effect on the other formations. The shale ard sand gradation show that shallow water conditions prevailed in the northern part of Eastside Field, while deeper water conditions were present in the southern portion or Westside Field. This fact seems to be true of the other formations, showing that the northern part of the district represents near shore deposits, while deeper " water formations appear to the south, the gradation being gradual. The formation below the Santa Margarita basal sand beds is known locally as the Big Blue, but owing to its sta- tiographic position and lack of fossil evidence, it has been assigned to the Monterey, being its probeble northern littor- al representative. The appearance of a white, siliceous shale, apparently Monterey, in place of the Big Blue in the southern part of the Coalinga distriet evidently supports this correlation. The Monterey (?) or Big Blue consists of two to three hundred feet of blue shale with a little light gray, fine sand. It is usually sticky, tough clay, becoming slight- ly more sandy to the North and East, where red shale layers are interbedded at various horizons. Water sands are re- ported in the Big Blue at different points, probably being lenses, Some 0il occurs above the Big Blue in one locality in the Bastside Field, and since sulphur water is reported at the same horizon further down the strike of the anticline, it seems probable the 0il has been carried to its position by underground water circulation, perhaps passing through a porous locality in the shale, or a local fissure or fault, which wes rendered impervious by the "tarring up" of the form- ation, before much oil was lost from the main reservoir. The presence of sulphur water in most localities about one hun- dred to two hundred and fifty feet below the base of the lon- terey renders the tough shale beds illogical points to shut 10. off water. The evidence of various logs showing rapid changes in the charscter of the upper strate of the underlying beds, while the lower strata are continuous in general character, supports the statement that an unconformity exists between the Big Blue and underlying beds. Owing to deeper water con- ditions in the Westside Field, the underlying beds are mainly blue shale, which renders its exact location hard to place. This shows that all the so called Big Blue of the Westside Field are not llonterey as applied to the beds in the Bastside. The lsck of sufficient data to make proper correlation may have led previous writers to this opinion, which also intro- duced confusion in the proper assignment of the oil zones. The unconformity between the Big Blue and lower beds renders the as~ignment of the latter to the Vaqueros, structurally correct. The Vaqueros consists of five hundred to seven hun- dred feet of blue shele, brown, and bluish sands, sulphur water sands, tar or trace oil sands, brown shale and oil sands. The zone above the main sulphur weter consiste of blue shele in the Westside, gradually becoming more sandy toward the Basteide, until sand or a sandy shale predominates over the anticline. This area, denoted by dots in the Rast- side, was noted on the logs as sand chiefly, or sandy shale, so should have had a few more shale lines to indicate this fact. Bearing this in mind, it mst be seen that the tran- sition from blue shale with some red shale and sandy layers to 11. a sand or very sandy shale in the Eastside can be clearly noticed on a log taken with usual care. A "trace" oil sand has been reported in the Va- queros just below the Big Blue in the anticlinal structure. This sand becomes more productive eastward and northward, meking wells of thirty to fifty barrels, but owing to the wealth of the lower sands most wells are drilled to the low- er horizons, Mud of the so-called water troubles in the Eastside are caused by the fact that when the Monterey (?) is passed through, and an oil sand struck, having a small production, the wells are cemented, although water with usually mech sulphur occurs lower in the formation, Most of the wells reporting water in the oil sands have reported sulphur water, which must have been due to their cementing off before the sulphur bearing sands were passed, or to the fact that neighboring wells have not cemented properly, al=- lowing water to get into lower sands, The selection of a proper point to cement the wells varies in character in the two fields, though not in horizon. This is one of the most important facts brought out by this section, and explains the many failures in shutting off water in the Eastside. The sulphur water sand noted on the section is shown by the well logs to be a continuous horizon reporting traces of oil in the upper part of the fsbo cline, where oil will naturally congregate near the top of the water. The quantity of water varies in localities,probably due to local conditions, such as a variation in coarseness of the sand 12. | or cementing material, perhaps being rendered silicified or calcareous by underground waters, thus varying the yield of water, In the Westside field the sulphur water sand is easily noticed, as no continuous tar or oil sand occurs above | it, and it is sand in the midst of a predominately shale bed. The tar sand occurring one to two hundred feet below the sul- phur water sand carries water with traces of sulphur in many localities, This water may have got into the sand through wells, as many are cemented lower, or may have been originally in the sand. This fact compels the cementing of the wells below the tar sand, and most carefully in the second brown g8hale below the tar sand, as the intermediate sand might be water-bearing, The existence of local sand lenses carrying water in the immediate vicinity of the oil sands has been shown by the Nevada Petroleum, and must be guarded against, The chief indicators to be watched in the Westside are sulphur water, tar or trace oil sands and brown shale. Approaching the Eastside the problem of cementing becomes more difficult, and requires a closer watch on the formations, so as to avoid the sulphur water and its probable seepage. In the deeper portion of the syncline, the wells can best be cemented about two hundred feet below the sul- phur water sand in a tough blue shale below shaly sand beds. On the steep side of the anticline an oil sand will be struck above the sulphur water, then sulphur water a few hundred feet lower, and two hundred feet below will be a second oil sand 13. with little commercial value. Sandy beds predominate just over this sand. After the oil sand comes a few hundred feet of tough blue shale, which forms a cepping for the main oil beds and offers the best solution for a point at which the wells can be cemented, The mistake of cementing off above the sulphur water should be guarded against, Below the oil sand mention- ed as occurring below the Big Blue is about three hundred and fifty feet of chiefly sand, or very sandy shale with a few shale lenses. Sulphur water occurs in the lower part of this series, but is much harder to determine exactly than in the Westside, due to the fact that the strate is sandy, per- haps allowing the water to be scattered through a longer dis- tance, resulting in a less flow; and also the sand will not be noticed among other sands as well as if in the midst of shale beds. The oil sand at the base of the sandy series is not very productive, so the best point to cement off the wells would be about twenty-five or fifty feet below this sand in the tough shale beds, which occur at this point. This would eliminate any possible sulphur water or ground water, and it seems highly improbable that any water occurs in the oil sands themselves, unless due to improper drilling. The oil sands have been traced through this section with much care, and the main sands have been held distinct from the tar or oil sands, which are not continuous and only productive in localities. 14. In the Westside Field, the upper two sand zones are the main sources of production, and most of the wells stop in a blue shale, but a few have reported a lower sand below about fifty feet of blue shale. Since these wells are at a distance from each other, and their upper formations can be well correlated for formations and position, the pre- gence of a third sand zone is shown to be the usual condition, Wells obtaining small production from the upper two zones due to position or local conditions should penetrate fifty to one hundred feet in search of a better sand. The most clear indication of the Tejon is brown shale, not in a nar- row belt, but & massive formation. There are certain con- siderations which cause an exact statement concerning the kind of oil impossible. In the Eastside the lower sand is a few degrees lower in gravity, but this is not always liable to be the case, since the relative coarseness of the sand , its cementing material, thickness and relation to overlying and underlying beds have their effect, Since it has been clearly shown that an unconformity exists between the Tejon and Vaqueros, then the nature of the local unconformity and its relation to the oil bearing formations in the Tejon will have an effect on the quality and quantity of the oil. The Tejon is waterbearing at certain horizons, so that the pre- gence of these water sande at or near the lower oil sand must be considered, as the disturbance produced by the pumping of 0il might induce a water-flow from below, A few wells ob- tain a good production from the lowest sand with no water, 15, but some have found salt water lower in the Tejon. The shale and sand dividing the second and third 0il zones becomes more sandy to the northas other formations do, and seems to become an oil-bearing zone on the dip of the anticline. A thin lense of shale comes in at this point to divide the first zone, and gradually increases in thick- ness to the north. The data given in this vieinity was sup- plied only by two wells, which indicated the sands as drawn. Even if any carelessness occurred in reporting the oil sands, the essential facts remain the same, that three sand zones will be encountered. The fact of the gravity of oil cannot correlate one zone with another, for it has been shown many times in the Coalinga field that the oil varies four or five degrees in the same 2zone. Different factors influencing the gravity of the oil are: size of sand drains, kind of cementing ma- terial within the sand, distance from outerop or downdip, ori- ginal composition or source of oil, kind of material through which the oil diffused in coming to its present reservoir, and also its present or post association with water. The middle light oil zone is usually fine grained, while the upper and lower sands are coarser and contain heav- ier oil. This may be due to the ability of fine grained materiel to hold the lighter hydrocarbons, which are more volatile. from the larger interstices. The fine grained gands also prevent gravitional sorting, because in interstices surface tension checks motion necessary below a certain size ) 16. for gravitional sorting, thus preventing the escape of the lighter hydrocarbons through the outerop. Gas can move along very fine sand beds, where oil would move very slightly, and as each bubble of gas carries a pelliele of the lighter oil, the sands are gradually filled with oil of a higher gravity than the nearby coarse beds. a —— Ww me WR SS a ee -—— a We We a we a The Standard 0il Company have drilled #.80 on Section 28 through the Vaqueros, then nine hundred feet of brown shale and six hundred feet of blue shale into a paraf- fin oil sand, whieh yields about ninety barrels per day. This sand by position and formation is a similar sand to those tapped by the Home 0il Company on Section 20 T 19S, R 15E. The productive sands in that locality dip to the southeast, also inereasing in oil content to the southeast, where favor- able sand reservoirs are found, This oil has been assigned to the Creteceous, since it only occurs in beds immediate to the Cretaceous rocks, and only when the purple shale of the upper Cretaceous is present, It ig probable that the oil is in the Tejon, and its high naptha and paraffin content indicate a secondary oil, which has been fractionated by dif- fusion, This has been shown possible by the experimentation of J. E. Gilpin, we GW ee WE WR Bee Wee We ee We AS ee WT SM Se A a A possible theory along these lines would be that blue shale in between brown shale in the Standard Well represents a change from oil forming strata to barren strata, and then back again, The blue shale might have been of the proper character to diffuse oil like Fullers earth does, so that the upper part would contain naptha and paraffins chiefly. The mein mass of the oil probably entered the Vaqueros through any unconformity as a heavy oil unaltered by diffusion. The lighter diffused oil fn the blue shale was then collected later by underground water and stored in the sands. This theory represents a probable hypothesis, for it has been prov- ed that heavy oils can be fractionated by diffusion. The diffusion varies with composition of material, size of grains, heat,and presence of certain compounds like salt, gypsum and bromide or iodine salts, The region to the immediate south of Section 20 has been shown unproductive for paraffin oil sands, but indi- cations point to a favorable production to the southeast, as is shown by the Standard well. The strike of the anticline was determined by another parallel section, and computed to be at en angle of sbout 30° with the strike on the U. S. G. S., map on Section 28. The gtrike of the projection of the upper oil sand runs from a point 2440 feet east of the IW corner of Section 36, in a di- rection 5 22° §, This shows that the anticline would proba- bly run in a slightly curved line through Section 33 about one quarter mile west of the anticline line on U. 8. G. S. mep, and about one half mile west on Section 34. I believe 18. that the anticline will be oven fsriher out than I nave indi- cated. The Peerless 0il Company might sink a well in their northeast corner and it would do much to show the true under- ground réletions, and indications seem to show that oil will be struck between 2500 and 2700, instead of3800 feet.. | This well might open up a large territory which 1s at grongil | considered too deep for the present market value of oil. The light oil found by the llohawk sees to indicate a better grede of oil throughout the deeper field far from the outcrop. Te W. X.,on Section 2,1is the only oil company of- fering date on the deeper part of the anticline, and making correction for elevation and position on dip between #2 and #2, the depth of the oil sands bear out my statement that the top of the anticline is further southwest. The section and study of these fields miles apart have shown that their oil sands are continuous zones, and not local lenses, as in many oil fields. The amount of oil act- ually in sight will tale many years to pump, and the limita- tions of the field are unknown. It is probable that water is beneath the oil further down the dip of the anticline, per- haps following it up slowly, so that there may bre a south- easterly limit to the production, end wells in the very deep territory may be the first to have water troubles. The steady yield of the wells with slight decrease of oil and little or no water seems to prove thet the coming of the water is many years away, for its presence will be felt long before the oil is exhausted. 19. Considering the immense size of the Coalinga 0il Fields, their favorable structure for oil accumulation, and lack of vital water troubles, the future is very promising for a long steady yield, with much room for future development, ORIGIN OF SULFHUR WATER. The association of sulphur water with certain form- ations in the Coalinga Field has been noted in the structural study, and the intimate relation between the oil and sulphur water has been shown. It is true that many wells have sul- phur water without traces of oil, but the same sulphur water higher toward the anticlines or outerop has oil, because of the well known fact that oil flowe on water; hence the lower water would contain little or no oil. It is also possible that the oil or carbonaceous matter may be oxidized, leaving the sulphur water as a residue. The intimete association of sulphur, chiefly as HpS, with oil and gypsum has been noted in many other oil fields, and experimentation has proved that decomposing organic metter reduces the sulphates of the sea to sulphides, which by reaction with carbonic acid yield hy- drogen sulphide, according to the reaction:- CaS ¥ 2 COg CaCOz # HgS HN CaSO4 + 2 C Cas + HpCOz This readtion has been shown by Murray end Irvine,in Trans. Roy. Soc, Edinburgh, Vol. 37, p. 481, 1€95, to be particu- larly effective in "blue mud." Applying this idea to the sulphur water in Coalinga, it is seen that the oil and its associated carbonaceous matter act on the various sulphates, such as gypsum, which are abun- dant, reducing them to the carbonate, and causing the produc- tion of sulphur water, which is HpS in solution in water. cl. The presence of blue shale or clay surrounding the sand favor- ably incresses this action, resulting in a stronger sulphur water in the Westside than Eastside field, although the cir- culation would tend to keep the fields of equal strength. 22. POSSIBLE ORIGIN OF OIL. The oil in Coalinga is most probably derived from giliceous shales in the Tejon and Cretaceous, principally from the Tejon, which is composed of 78 per cent silica, much being in a finely pulverized state, BS — - — —— —— n — — S ee BE SW Wee BAe fe SB a BS oe R.C.Wells, U.S.G.S. BULLETIN 398, pp 66 - 70. Se — —— ee ee a. SAW See Se gee Re We SE Se She Gee we GOR SE SE ea WE gue gee SER Ge GE Ne We ee SRE SNe ee See ee Se BS — The brown color of the shale ard carbonaceous appearance with cracks lined with sulphur makes it difficult to realize that the organic matter in the diators was the source of these fea- tures and the oil in the beds above. The majority of pure deposits of diatomaceous earth usually present a white, chalky appearance with no great discoloration due to organic content, mich less do they impregnate adjacent beds with oil. The presence of sulphur in the 0il is not necessarily a sign of animal origin, for it has been shown in this paper that sul- phides are formed from various salts by the reducing action of carbonaceous matter. This fact seems to indicate that the organic material in the diatoms and fossils must have been supplemented by other sources to produce the enormous organic decoloration and production of oil. A possible supplementary source for oil would be the chemical and mechanical precipitation of organic matter in solution in river or bey water by salt weter,accormpanied by a precipitation of colloidal or finely divided silica. 23. The chemical, geological and historical evidence supporting this statement seem to suggest very strongly its truth, although not conclusive. The general correlation of facts will be given as briefly and conclusively as possible. The analyses of present day rivers show that cer- tain rivers,chiefly in the tropics or & "peaty" country, con- tain much organic matter in solution, chiefly in the form of humus acids. Ref:~ ¥? W. Clark - Data Geochemistry -- Analyses of Rivers of the World. Amount of soluble matter in rivers. BULLETIN 491, U. 8. G. 3S. Bg Wf WS RS ae We BE Ge SR ase Se EG ee SE GR ee Se ee SE RR ee Se SR SE SR ee SE a We Se Se a ae ee a SE Se This amounts to even sixty per cent of the total matter in solutions. When the amount of soluble matter in large rivers amounts to millions of tons per year, the amount of organic matter is very large. It is found that with the inerease in organic matter comes an increase in free uncombined giliea in most cases. By chemically equating the positive ions to the negative ions in the analysis, I found that there is an excess of free silica, apparently in a colloidal state, varying from a fration of one per cent in rivers with little organic matter to forty-four per cent in tropical rivers, such as the Uruguay. The relation between the silica and hums is not clearly understood, and prominent chemists have given conflict- ing views concerning the physical and chemical relationship. —————————————————————————————————_——_———]—_——_———————————— Ref:- P,Thenard, Compt. Rernd., Vol.70, p. 1412 (1870) C.W.Hayes, BULLETIN Geol.Soc.Am., Vol.8, p.213, (1896) TB tS ———— C—O — ]—-———{——_——_ 0. Wa. Wa. -—— - ———_—— 24, These ideas do not have any direct bearing on my theory, but it would be well to state the more probable explanations, cor- relating and conbining the facts, which offer any aid to a proper understanding of the theories involved. Large rivers contain little silica in solution, ex- cept where & large amount of organic matter is present. The corbined silica is chiefly in the form of sodium metasilicate, which has been shown by Kohlrausch and others to be hydrolyzed in solution into colloidal silica and sodium hydroxide. Sg Wf BE a SE Ge Ge ES Ge BE Se ae we WE a WE eee we US gue SR ga A TE Ge wee SR ee GE eee GS Ref:- Xohlrsusch - Zeitschr. Physik. Chemie, Vol.1l2, p. 773 -- 1893, L. Kahlenberg & A. T. Lincoln, Jour Phys. Chem, Vol. 2, p.77 -- 1898, — A —— ——— a GW Ga Ge Ge SE eee GE WG Gee WE Ge Se WS ES en ee SE NS We SR ge Sg Se Ga Unconmbined silica must be present as colloidal silica, since silicic acid hydrolyzes, forming the colloidal solution. A colloidel suspension is finely divided solid matter in the presence of the solvent. It has not been definitely settled whether these colloidal suspensions manifest any of the properties of true solutions. There is satisfactory experimental evidence to prove that the colloid particles are charged electrically, certain being positively charged, while others, such as colloidal silica and sulphur, have negative charges. — C—O —— WW WW SN GER me GE SE Wee ee ee ee de SS WW ae SBT ER me We ee SE a WR ee se ae see We ee ee SR a a Refs:- Jones, Physical Chemistry, p. 285 -- 1907. Coehn, Wied. Ann,, Vol. 64, p. 217 -- 1898, Whitney and Ober, Jour Am, Chem. Soc., Vol. 23, 1901, p. 844, a —— ee Ga Ge TEE Ge aa Se WR We Gee Se SE See See me TM ee SE ee ee Sn SS a a Thus it has been shown by layer, Schaeffer and Terroine in a series of tests that the addition of traces of an alkali to an ultramicroscopic suspension had the effect of increasing the size of the colloidal granules if the suspension was posi- tive, and diminishing them if suspension was negative, end the additions of acids produced the inverse effect. WS ————————————_—— —_g— a wD gyn Ww WE ee We GS wwe Se Sh a A a Ref:- Mayer, Shaeffer and Terroine, Compt. Rend, Yol. 145, 1907, pr. 918-920. WB dW Ge GE we ee WW ge ee ST ee ae a Sg It seems possible that the negatively charged colloidal silica would have the size of its particles decreaced in size and in- creased in number by the presence of humic acids. This is a probable explanation for the usual reletion of high organic to high silica content in river waters. A strict rule of the relatively solubility cannot be applied, for the action would vary with the solvent, depending upon the salts and alkalis present in the water, and the density and terperature. The coagulation of the colloids is effected by elec- trolytes, such as Alp(SO4)z, Feg(S04)zs FeClz, and other salts when present in sufficient quantity. Burton has shown that a marked difference in potential exists between the colloidal perticles and water. This diminishes the surface tension be- tween the two, and there is nothing to draw the fine particles together into large particles, and produce a precipitation, When a sufficient electrolyte is added to the colloidal suspen sion, the colloidal particles attract the oppositely charged ions, and the difference in potential between the colloidal particles and water becomes less and less, inereesing the sur- 26, , face tension. The colloidal particles are drawn nearer to- gether and are precipitated. TS —————— Wh WL WW ow We WEN Se ee GS RA a WW WE Wt ——————————— o— i Wan— WG We We Wa A The coagulation of the organic matter and silica in solution can be effected by sea water,due to the presence of the needed electrolytes. This is possible chemically accord- ing to the best chemists. That it actually exists is shown by analysis of water for organic content at London, when the water has been affected by sea water; and on verious rivers where the effect of salt water has beer noted. WT — ——— —— — WW Wg Ww ge WE WG ge We We WW a C—O ——_—— WS W—_— Refs:- Water Purification, p. 118, London Inst. lin. Zng. Proceed ngs 1912. Fe HF. S. Shelton, Chen, Soc, London Proceed., p.110,19D TE ————-—————————————— ou w— WV —— a a Ww gee a WE GE SE GE WN ee Gee ae See we The Transactions of London Institute of Mining and lMetallurgy for 1912 contain observations by Bunney on the peat mosses at at Down Holland, where he found petroleunm being formed from de- composition in presence of an infiltration of sea water. The analysis of a typical peat will show its relation to the humus acids under consideration. Water 20.07% 29.5 Ash 3.0 3.05 Fiber 47.0 54.95 Furs 30.0 12.50 Acids a We a Refs:- Analyses by H. Bourtr#ger, Zeitschr. Anal. Chemie. Vol. 39 -- 1900, p. 694, TI ——————_————-_— en S———————————__- oo —— 1 —-_——— o_o" ———— a — In Coalinga, the Tejon has a poor grade of coal at _7. certain horizons, showing conditions favorable for the genera- tion of humus acids on the land areas. The absence of paraffin hydrocarbons in the soil, al- though they are concentrated in extensive deposits in localities, seems to indicate the existence of an intermediate orgeric com- pound between the complex plant compounds and the paraffin hy- drocarbons, and evidence points to the humus acids, which are probably collected by surface waters and concentrated by sea water in the formations where they are found today. The vegetation in the Eocene and up to middle Miocene in Californie indicate a warmer, more humid climate than the present day, presenting conditions similar to the tropics today. TE ee a SG ann ge. ee GS we a a a Wa WS Refs:~ Age of lammals, F. F. Osborn, pp. 93-95-282. THN —————————————————————————————_——_——— WW. WW a WW mw SS The lack of carbonaceous material in the formations has been one of the reasons which disapprove a plant origin, but the coagulated organic matter, silica, and sediment would contain little fibrous carbonaceous material. An interesting comparison is the fact that below the carboniferous strata in the Bast is found beds of lime and iron compounds, which may have been due to the leaching action of the humus acids from the peaty coal beds. Beds of arorphus gilica are also found with the iron carbonestes in the Penokee iron region. C—O ———————— a —— C—O ————— Refs:- R.D.Irving and Van Hise, Tenth Ann.Rept. U.S.G.S., pt. 1, 1890, op. 397. C.R.Ven Hise, U. S. G. S., Vol. 47, 1890, p.847-853, UD TA — —"—" —_—_—__—__—_—_—_——_ o_o" {o_o —_— = miner. ls Céhoretions of lime and iron “also occur in the brown shaleg of 28. Coalinga, increasing in size and quantity in the upper vart. The work of Binney in showing the formation of oil in peat bogs from infiltrating sea water may mean that the presence of sea water is necessary for the chemicel change from humus acids to oil, which may have prevented oil formation in the Rast, but the relation of the iron and coal beds to the oil sirata are not clearly worked out, so a definite statement is impocs- ible. Refs:- R.D. Irving and Van Fise, Tenth Ann. Rept. ¥, 5. G. 3. p%.1l, 1890, 7p. 327. The presence of some diatoms and forsminiferal in- dicate that the material might have been precipitated far from shore. It is well known that river waters take many miles to " mix with the sea. The Challenger exredition has not worked mich on deposits near great tropical rivers, but reports were made of a brown mud found miles off the coast of tropical Africa being ascribed to river sedimentation. The fadt that sea water contains hardly a trsce of silica in any locality, and sili- » fn EY ceous organic oozes occur along the "mud line," seems to sup=- plement the other statements in this paper. The association of siliceous deposits in merine stra- te in California with oil deposits in tie Zocene and I'iocene periods, and the extensive deposit of oil indicating ebnormel orcenic derosition, such as cannot satisfactorily he exnlained 29, by marine origin alone, seem to indicate by chemical, geolo- 2 ft and historical evidence that the oil may have been de- £ica C rived from the precipitation of organic material. END OF TITLE