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4v

Topographic and Geologic Survey of
Pennsylvania.
RICHARD H. HICE, State Geologist.

Geologic Map of Southwostern
Pennsylvania.
REPORT NO. 2.

HARRISBURG, PA.
WM. STANLEY RAY. STATE PRINTER
1914.
“F.
(2):
CONTENTS.
Illustrations,
The Geographic Base, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
The Geologic Map, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
The Geologic Section, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Rocks of Southwestern Pennsylvania, . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Carboniferous System, .- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Permian, or Dunkard Series, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Greene formation, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Washington formation, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pennsylvania Series, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Monongahela formation, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conemaugh formation, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Allegheny formation,
Pottsville formation, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Mississippian Series, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . ..
Devonian System, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Structure,
General Statement,
Method of graphic representation, . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Method of determining structure, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
The structure as represented, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Horizontal sections, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I 0 O I O I I a Q I Q a I 0 u I I I I 0 l O Q O Q I I I I I l I I I 0 0 I b I 0 I I I 0 0 0 I I c I t 0 0 I I I a I n‘
I I 0 I 0 u I l u 0 I n a I I t Q l q 0 I 0 0 n 0 o o I o Q n o I 00
I a I o c 0 I I I I 0 I I Q I l h 0 I v q I 0 u n Q I 0 I n n O l q l I 0 Q u n n I I o I c a n u Q u Q I u I I o u I u n an
I a Q a u 0 u I o g I 0 0 a Q u l I I n o O Q I n u t O I i n n I I a l 0 u I c o o I I I
368987
(3)
M "3% “3;” (“Egg-“ta
“ii figgqéafgs
(4“).
Plate 1.
Plate II.
Plate III.
Plate IV.
Plate V.
Plate VI.
Plate VII.
Plate VI-II.
Plate IX.
Plate X.
ILLUSTRATIONS.
Areal geology of southwestern Pennsylvania.
Structural geology of southwestern Pennsylvania.
Sketch map showing location of horizontal sections.
Geologic section through Uniontown, Connellsville, La-
trobe, Elders Ridge, Rural Valley and Clarion quadran-
gles.
Geologic section through Beaver, Carnegie, Brownsville,
and Unionltown quadrangles.
Geologic section through Mason'town, Connellsville, La-
trobe and Indiana quadrangles.
Geologic section through Rogersville, Claysville, Burgetts-
town and Beaver quadrangles.
Geologic section through Beaver, Sewickley, New_ Ken-
sington, Freeport, Elders Ridge and Indiana quadran-
gles. .
Geologic section through Claysvrille, Amity, Brownsville
and Connellsville quadrangles.
Geologic section through Rogersville, Waynesburg, Mason-
town and Uniontown quadrangles.
(5)
T O
..L.’
((56))
THE GEOGRAPHIC BASE.
The area embraced in this map covers forty—eight 15’ quad-
rangles in the southwest portion of the State, together with
portions of nine quadrangles along the western boundary of the
State (a strip about one mile in width) and a strip along the
southern boundary of the State, embracing portions of eight
quadrangles which lie for the most part in West Virginia and
Maryland. The total area embraced in the map is 11,227
square miles, being 2-1.9 per cent. of the total area of the State.
Of the forty-eight quadrangles entirely embraced in the map
all but ten have been mapped topographically, those remaining
unmapped being the Penfield, Reynoldsville, Brookville, Wil-
pen, VVindber, Stahlstown, Hyndman, Berlin, Meyersdale and
Confluence. The narrow strips of the quadrangles along the
western and southern boundaries of the State have all been
mapped topographically.
The geographic base used is far more accurate than any map
of a large portion of the State heretofore issued. In the prepa-
ration of this map the topographic sheets of the quadrangles
which have been mapped were carefully reduced, and the por-
tions of the map thus covered are far within the possible accu-
racy of a map on this scale. This reduction was from the
scale of 162,500 of Nature, approximately 1 mile to the inch,
to a scale of 1-500,000 of Nature, or 8 miles to the inch.
In addition to the detailed topographic work there was
available a large mass of data of great accuracy. Surround-
ing the published topographic sheets there is in all cases a strip
of accurately mapped territory embracing portions of the
unpublished areas. Over all the area embraced in the map
work has been done towards the final completion of the topo-
graphic map. This consists of what is known as “Primary
control,” which is the accurate location, far within the possi-
bilties of the map to depict, of a number of prominent points
which can be used for reference in the preparation of the
detailed map of the region. All these accurately located points
(7)
8
were carefully assembled in the work of the preparation of
the map, and the data available from other sources was ad-
justed to these locations. The result of all this work was a
map in which the accurate location of all points, streams and
boundaries, falls well within the possibilities of the scale to
show.
The map was constructed by the United States Geological
Survey as a portion of the millionth map of the world. It
was constructed on a scale of 1-500,000, and for use in State
work was enlarged to 1-250,000, approximately 4 miles per
inch.
THE GEOLOGIG MAP.
In the_preparation of the geologic map all known sources of
information were used. A number of the quadrangles which
have been mapped topographically, have also been mapped
geologically under the co-operative agreement between the
United States Geological Survey and the State Geological Sur-
vey. The reports of the Second Geological Survey of Penn-
sylvania have been freely drawn upon, and other sources of
information utilized as fully as possible.
Where the various quadrangles have been mapped geologi-
cally, the work has been published on the scale of 1-62,500 of
Nature, approximately 1 mile to the inch. In reducing these
maps to a scale of one-fourth the published size it is obviously
impossible to retain the details and all the individual forma-
tions depicted on the large scale map. These, therefore, have
been in some cases combined.
' The reports of the Second Geological Survey of Pennsylvania
are filled with detailed geologic sections. Where the areas
have been mapped topographically it was possible in most
cases to accurately locate many of these sections and therefore
to show well within the scale of the map the position of the
formations given in the detailed sections.
Where ‘topographic maps were not available the geology as
indicated in the reports of the Second Geological Survey, with
such changes as it has been possible to secure from later
sources, has been adjusted to the new and better base of the
present map.
9
It will be thus seen that geologically the map is of three
degrees of accuracy. (A) Over much of the area the extent
of the formations as shown’ is far within the scale of the map.
(13) Over another portion of the map, where the topographic
maps were available, the geology is also believed to be well
within the possibilities of the map. (O) A third portion of
the map, mainly in the southeastern area, possesses less accu-
racy, but owing to the better geographic base and the recent
geologic work along the Maryland line, it is believed the forma-
tions are more accurately shown than in any preceding map.
THE GEOLOGIO SECTION .
No attempt is made to indicate on the map the unconsoli-
dated rocks on the surface, which belong to the Pleistocene, or
last geologic age. These unconsolidated materials consist of
glacial debris, and of the materials of decay from consolidated
rocks, which either remain in place or have been moved by
running water into the streams, and are now found as alluvial
benches or terraces along many of them. A portion of the
material of glacial origin has also been washed down from
the more northerly latitudes, and has been spread along the
streams in terraces, or is found in a thin layer of outwash
upon the underlying consolidated rocks. While these forma-
tions are of great interest geologically, and also from an
economic standpoint, it was not thought best to show them on
this map.
The consolidated rocks over most of the area shown belong
to the Carboniferous age, although the southeastern portion
of the area mapped embraces rocks of older age, down to the
time of the Trenton limestone. The principal divisions of the
rocks found in the area mapped, with their recognized geologi-
cal age, is shown by the following table:
10
BOOKS OF SOUTHWESTERN PENNSYLVANIA.
Carboniferous—
Permian, or Dunkard Series. (“Upper Barren Measures”)
Greene formation.
Washington formation.
Pennsylvania Series. (“Coal Measures” Groups).
Monongahela formation, “Upper Productive Measures.”
Conemaugh formation, “Lower Barren Measures.”
Allegheny formation, “Lower Productive Measures.”
Pot-tsvrille formation.
Mississippian Series, or “Lower Carboniferous.”
Mauch Chunk formation.
Burgoon (Logan, “Big Injun”) sandstone.
Cuyahoga shale, (limestone, and sandstone)
Berea (Corry) sandstone.
Catskill—Erie—
Knapp formation.
Conewago formation.
Devonian——
Chemung formation.
Portage formation.
Genessee shale.
Hamilton and Marcellus formations.
Oriskany sandstone.
Helderberg limestone.
Silurian—
Waterlime group.
Salina group.
Niagara group.
Medina group.
Ordovician (Lower Silurian)—
Hudson River shales (Lorraine).
Utica shales.
Trenton limestone.
GARBONIFEROUS SYSTEM.
' PERMIAN, OR DUNKARD SERIES.
4‘
The youngest consolidated rocks in the area covered by the
map are the upper portion of the Garboniferous,* the Permian,
or Dunkard Series, as named by Dr. I. G. White in 1891, from
their exposures along Dunkard creek in Greene county. In
the earlier reports of the Second Geological Survey and in the

‘The only known exception to this statement is a. small igneous dike (peridotite) in
Fayette and Greene counties. See Top. and Geol. Surv. 00m. Rept. 1910-1912, p. 150.
11
reports of the First Geological Survey, these beds were known
as the “Upper Barren Measures,” as it was believed at the
time they were thus named they did not possess coals of work—
able thickness.
These rocks embrace that portion of the Carboniferous sys-
tem lying above the top of the Waynesburg coal. They are
largely confined to Greene and Washington counties, although
small patches still remain in Fayette, Westmoreland and Alle-
gheny counties. The general dip of the rocks in this region
. is towards the southwest, so that the greatest thickness in this
State is near the southwest corner of Greene county.
The Dunkard series has been divided into two formations,
the Greene, extending from the highest of the known rocks
to the top of the Upper Washington limestone, and the Wash-
ington formation, embracing the rocks from the top of the
Waynesburg coal to the top of the Washington limestone.
The total thickness of both formations in this State is about
1,200 feet, and how much has been eroded we have no means
of knowing.
PEN N SYLVANIAN SERIES.
Monongahela Formation.
This formation in early reports on the geology of the State
and in some of the reports of the Second Geological Survey,
was called the “Upper Productive Measures.” It extends from
the top of the Waynesburg coal down to the bottom of the
Pittsburgh coal. This formation underlies the wide expanse
of the Permian Series in the southwestern portion of the State
and outcrops beyond it to the north and east, occupying a
considerable portion of Allegheny, Fayette and Westmoreland
counties. There are small areas also found in Beaver, Indiana
and Somerset counties, and five small remnants have escaped
erosion in the Broad Top coal field of Huntingdon, Bedford
and Fulton counties. The thickness of the formation in Penn-
sylvania varies from about 350 feet to 400 feet.
This formation is of value, economically, from the fact that
it embraces the Pittsburgh coal bed, which is almost uniformly
of workable thickness and purity wherever found in Pennsyl-
12
vania. This bed produces approximately 60 per cent. of the
bituminous coal mined in the State. Other coals in the
Monongahela formation are locally of workable thickness.
Oonemaugh Formation.
Immediately underlying the Monongahela formation occurs
a series of rocks, 500 feet to 700 feet in thickness, which the
early geologists of Pennsylvania termed the “Lower Barren
Measures,” from the fact that they were supposed to contain
no coals of value. This series, which extends from the top
of the Upper Freeport coal to the base of the Pittsburgh coal,
is now known as the Gonemaugh formation, from the stream
of that name. -
The Gonemaugh formation occupies a very large portion of
the area embraced in the map, including portions of Wash- _
ington, Beaver, Allegheny, Butler, Armstrong, Indiana, West-
moreland, Fayette and Somerset counties, indeed being found
in all the counties embraced in the map, with the exception of
Greene on the southwest and Bedford on the southeast.
Allegheny Formation.
This series of rocks, extending from the top of the Potts-
ville sandstone to the top of the Upper Freeport coal, or the
base of the Mahoning sandstone, was ‘known to the early
geologists of the State as the “Lower Productive Measures.”
[t is to be distinguished from the underlying Pottsville by
the greater prevalence of workable coals and the smaller
amount of sandstone contained. It can be distinguished from
the overlying Gonemaugh formation by the presence of several
workable coals, the best known and defined being, in ascend-
ing order, the Brookville, Clarion, Lower Kittanning, Middle
Kittanning, Upper Kittanning, Lower Freeport, and Upper
Freeport.
In the area covered by the map the Allegheny formation
bounds the Gonemaugh to the north, and extends far down
the valleys into the overlying formations. It is also found
13
in irregular extension to the West Virginia line through the
counties of Fayette and Westmoreland, where it is brought to
light by the acute folding of that region.
The coals of the Allegheny formation furnish about 4.0 per
cent. of the bituminous output of Pennsylvania.
Pottsville Formation.
Underlying the Allegheny formation occurs the great Potts-
ville sandstone. It is not very prominent in the area covered
by the map.
In the northern portion of the map the Pottsville is found
in the valleys of the larger streams, occupying portions of the
Beaver, and middle parts of the Allegheny valleys. In western
Pennsylvania the Pottsville consists of three members, the
Homewood sandstone at the top, the Mercer coal group, and
the Conoquenessing sandstones. The economic importance of
the Pottsville in this area is quite small, aside from the flint
clays of the Mercer horizon, which are the most valuable flint
clays in the State.
MISSISSIPPIAN SERIES .
Except in the southeastern portion of the area covered by
the map, where they are brought to light by the folding which
has there taken place, the rocks underlying the Pottsville are
only found in a portion of the immediate Allegheny and Clarion
valleys. These rocks lie unconformibly beneath the Potts-
ville in southwestern Pennsylvania. This nonconformity ex-
tends throughout the region covered by the map. The Mauch
Chunk red shale, with the Greenbrier limestone, has a thick-
ness of about 200 feet in the southwest corner of the State.
separating the Conoquenessing and Burgoon sandstones. This
thins going north and east until, in the vicinity of Pittsburgh,
the Conoquenessing and Burgoon are in contact.
The rocks underlying the Pottsville are of great economic
importance in the area covered by the map, as they include
many of the more important oil bearing sands. The Berea
sandstone is regarded as the base of the Mississippian Series.
14
DEVONIAN SYSTEM.
The rocks underlying the Mississippian Series are only
known over most of the area covered by the map by well
records. These same rocks, however, are shown in a general
way in the southeastern portion of the area covered by the map,
where they have been thrown up by the folding.
Any discussion of these rocks throughout southwestern
Pennsylvania entails a study of well records, and is not in
place in describing a general geologic map, which only shows
the rocks exposed at the surface.
STRUCTURE.
From an economic point of view the determination and
delineation of structure is of the highest importance, and in
the geologic work done in co-operation between the United
States Geological Survey and the State Survey particular at-
tention has been given to this phase of the study.
in the report of the Commission in 1906-08, Dr. G. H.
Ashley explained the meaning of the word structure, and the
method of representing it in the folio publications. From his
report the following description is taken:
“General Statement. In the recent geologic work in which
the Federal and State governments have co-operated the de-
termination and delineation of structure has been considered
as of the highest importance, and a large share of the work
and its cost has been devoted to that side of the study. As
work in this direction is a distinct advance over the work of
the earlier surveys, and as men without engineering training
are not familiar with the meaning of the word as here used,
or the method of representing the structure in recent publica-
tions, the subject is here treated at some length and from a
very elementary standpoint. There are four phases of the
subject to be explained: (1) The meaning of. the word
‘structure’ as here used; (2) the method of its graphic repre-
sentation; (3) the methods of its determination in- the field;
and (4) the degree of accuracy and reliability of the structure
as presented.
15
“If it were possible to remove all of the rocks lying above
the top of any selected rock layer in western Pennsylvania,
such as the Pittsburgh coal, it would be found that the top
of the layer formed a surface like that of a gently rolling
country consisting, in the main, of low, rounded ridges or
swells between equally gently rounded valleys. The ridges
and valley would be found in western Pennsylvania to have a
general trend of northeast and southwest. Some of the ridges
and valleys would be found to be very long, extending some-
times half way across the State, but in all cases the ridges
would nose out and the valleys run out as two nearly parallel
ridges run together and coalesce. This would be true only
of the western part of the State west of a line which is fol-
lowed by the east side of Cambria county. For a short dis-
tance west of this line the ridges and valleys would usually
be quite long and narrow and regular. Further west they
would usually be shorter, broader, and less regular, until along
the western edge of the State this rock surface which we have
assumed to have been exposed would appear to be a gently
sloping surface, sometimes rising into oval or sugar-loaf
mounds and similar depressions, but in general sloping toward
a line drawn from Pittsburgh southwestward toward Hunting-
ton, West Virginia. Further examination would show that
this line was the axis of a major valley or basin, but that in
going eastward from this line, the ridges and valleys occurred
at higher and higher elevations. By structure here is meant
the ‘lay’ of any bed, or the shape of one of its bounding sur-
faces, as just described.
“The geologist recognizes that in the main these ridges and
valleys are folds produced by pressure from the southeast, as
a bolt of cloth partly extended on a counter and pushed upon
from one end will be thrown into many transverse folds or
wrinkles. To the up folds or ridges the geologist gives the
name ‘anticlines,’ to the down folds or valleys, the name of
‘synclines;’ the direction of slope at any point is the ‘dip,’
and a horizontal line at right angles to the dip along the bed
is the ‘strike.’
“Method of Graphic Representation. In attempting to rep-
resent the structure, three methods are used. One method is
16
by hachure lines, or some modification of them; that is, on the
map of the area involved, short lines are drawn in the direction
of the dip. Usually the part of the line down the dip is made
heavier than the opposite end. In this way it is possible to
show the direction of the dip, the position of the anticlines and
synclines, and, if the length of the line is varied as the dip
varies, it may be possible to suggest whether the dip is high
or low. In this method there is only one definite thing shown-—
the horizontal position of the axes of the anticlines and the
synclines. All the rest is indefinite, and the method has,
therefore, a very limited application from an engineering and
practical standpoint. The second method consists in assuming
that the rocks have been cut by a vertical plane and a draw-
ing is made which 1epresents the cut edges of the rocks where
they are intersected by this plane. Just along the line of its
intersection this method represents the structure with entire
d efiniteness and with as great accuracy as the facts observed or
obtained will allow. It shows not only the horizontal posi-
tion of the axes and folds at the points of intersection, but
their vertical position as well, expressed, it may be, in feet
above sea level, and the exact slope of the rocks between the
various axes of the anticlines and synclines, so that the exact
position, vertically and horizontally, of any rock being studied
may be determined. This is the most vivid way of represent-
ing structure. It has this great disadvantage, however—it
shows the structure only along the line of the section. If
the anticlines and synclines are long and regular such sections
a mile apart may give a very fair idea of the structure. If
the structure. be irregular the sections must be correspond-
ingly more numerous and near together. It is evident at once
that, while such sections may give accurate information of
the structure along the lines of the sections and general infor-
mation of the region in general, if it be desired to .get exact
information/as to the dip or elevation of any coal or other rock
bed or any point off from one of the lines of section, it can
only be done with difficulty, and at best, approximately.
“The third method is by one of use of contour lines. This
method, while not so readily understood, or so graphic in its
portrayal of the folding as the preceding method, has the great
17
advantage that it may be placed on a map with other features.
and from the lines as drawn it is possible to determine at any
point on the map the dip, strike and elevation of the rock
surface that has been contoured. To understand the meaning
of contours, let it be imagined, as before, that all of the rocks
above the top or bottom of a selected layer be removed and
that then the sea rises until just above the top of the highest
fold, say, to an even number of 100 feet above its old level.
Suppose now that it sinks 100 feet so that the top of the ridge
project slightly above its surface. If it remains at this level
a short time it might be assumed to make a slight beach mark
where the waters meet the ridge. Such a beach mark might
consist of a slight wave cutting in the rock or only of an
inconspicuous ridge of seaweed, sand, etc, such as is ordinarily
thrown up at high water on any beach to-(lay. Suppose the
sea then sinks another 100 feet and remains until another
beach mark has been made. Evidently the two beach marks
will show the exact shape of the hill at the elevations above
the old sea level at which the sea stood still. Where the
slope from the first mark to the second was gentle the marks
will be far apart. Where the slope was steep the marks will be
near together. Assume then that the sea continued to sink,
stopping at each even 100 feet long enough to make a beach
mark, until it had returned to its old level; that a map of
these beach marks had then been drawn and each marked with
the elevations at which it was made. Such a line, when drawn
on a map, is called a contour line. It is evidently a line of
equal elevation, in this case, above sea level, and a map show-
ing the st1 ucture by contour lines is called a structure contour
map. The elevation of any point on one of the contour lines
is, of course, shown by the designation of that contour line,
but it is also evident that if the slope between any two adja-
cent contour lines he, or be assumed to be, even, the elevation
of any intermediate point can at once be determined with
close approximation. Thus, if a particular point on a map
comes half way between 1,200 and 1,300~foot contours, its
elevations may be assumed to be very close to 1,250 feet. If
it be one-fourth the distance from the 1,200-foot to the 1,300-
foot contour, its elevation is close to 1,225 feet, and so on.
2
18 M
“So that if a map be made showing by 20-foot contours the
structure of the surface at the bottom of the Pittsburgh coal,
an engineer, by turning to such map, can see at a glance the
elevation above sea level of the Pittsburgh coal to within 20
feet, and usually within 5 feet, either at the point at which
he is standing or at any other point on the map about which he
is interested, even though the coal at that point be hundreds
of feet under ground. If, further, the map shows by contours
the elevation of the surface of the land at that point, by sub-
tracting the one from the other, he may obtain the depth below
the surface of the bottom of the coal and will know at once
how far he must drill or sink the shaft in order to reach the
coal.
“Methods of Determining Structure. In determining the
structure, two general methods have been used. The first
method is, briefly, to plot on the map all of the elevations of
the selected surface it is possible to obtain, and then to con-
nect them with lines of equal elevation. Thus, suppose that a
map is being made in the Pittsburgh coal field and the bottom
of the Pittsburgh coal has been selected as the surface to be
contoured. If there be any mines on that coal in the area,
copies of the elevation of the coal would be made from the mine
maps of the companies. These would then be reduced by pho-
tography to the scale of the field map and the elevations trans-
ferred to the field map. Then there would be added to the map
the elevations of the bottom of the coal at every point where
it could be found in outcrop, as at small mines or ‘country
banks,’ prospects or exposures in road, railroad or steam cut-
tings, or when seen as black smut marks across the roads.
If any drilling has been done to prove the coal, or if there are
oil or gas wells in the area which pierce the coal and the
records of which give the depth of the coal, the elevations so
obtained are added. When necessary, the elevations of the
tops of the wells are determined in the field. Then having
determined the elevation at the surface of other coals, lime-
stones, sandstones or other rocks that outcrop, and knowing,
or finding from a study of the stratigraphy, the distance from
the Pittsburgh coal up or down to the outcropping bed by
adding or subtracting, as necessary, a great number of addi-
19
tional elevations on the coal may be obtained, until finally
the field sheet of a single quadrangle may contain many hun-
dreds of elevations on a single horizon. Then lines are drawn
between points of equal elevation, the lines passing through
or to one side or the other of any elevation as the elevation is
just at, above, or below the elevation of the line being drawn.
“In this case, the reliability and accuracy of the final result
will depend upon two things: The abundance and uniform
distribution of the elevations and the accuracy with which the
individual elevations are determined. In the field .the eleva-
tions are determined by the barometer, by the hand level or
by the spirit level, or stadia. In all cases the measurements are
checked on or measured from bench levels intrumentally de-
termined in the making of the topographic map. Experience
has shown that where frequently checked on bench marks, as
in western Pennsylvania, barometric determinations will be
correct within 50 feet, though the limit of error is hardly
less than that. With the hand level the limit of error should
not be more than 5 or 10 feet, while with the spirit level, or
stadia, the limit of error should be well within 5 feet, and
generally within 1 foot. The liability of being mistaken in
the identification of the bed itself or of some other bed from
which its elevation may be computed, is a constant possible
source of error, as is also the constant possibility that the
interval from an outcropping rock to the surface to be con-
toured may have changed from what it is at the nearest point
at which this interval could be measured. This method, using
in the main the spirit level, has been applied in the Burgetts-
town, Claysville, Carnegie, Sewickley and Clarion quadrangles.
“In the second method, vertical cross sections are drawn to
scale so as to make a complete network all over the quad-
rangle. Ideally, every square mile should be crossed by one
or more of these cross sections. These cross sections are drawn
so as to follow in a general way routes taken in the field study
of the geology, such as the roads, railroads, streams, hill slopes,
etc. In making the field study of the geology, the geologist
draws in his note book a large scale profile of the ground as he
passes over it, and on this he represents graphically and with
- abundant notes every particle of geological data he can obtain
20
along the line he is traveling, not only actual exposures of the
rocks, coals, mines, wells, etc., but everything about the soil
or debris which may contain any clue to the character of the
rock below. All of these data are placed on his profile at
the proper elevation as determined by the barometer, hand
level or spirit level. In the office the data are transferred from
the field note book to the carefully drawn cross sections, the
elevations being carefully corrected for any errors in the
barometiic 1eadings where such can be detected. If the sur-
face data are at all clear, it is usually then not difficult to
draw what corresponds to the intersection of the plane with
the horizon which it is desired to contour. The cross section
paper used has horizontal lines, or they may be drawn to rep-
resent the vertical intervals at which contours are to be
drawn on the map. Where these horizontal lines cross the line
representing the position of the bottom of the Pittsburgh coal
on the cross section, if that be the surface being contoured,
or when the corresponding contour lines are going to cross the
line of the cross section on the map, these points of intersection
are drawn on the map and then connected together to form
the contour map. In this method use is made of the levels
from mine maps, drillings, etc., but all of the other data is
taken into account as well. WVith a similar mode of obtaining
elevations this method is much more accurate than the pre-
ceding. This is particularly true in the regions in which the
outcropping rocks are mainly or entirely of Allegheny or Lower
.lonemaugh age, as in most of the Barnesboro, Patton, Punx-
sutawney, Curwensville and Houtzdale quadrangles, and large
areas in some of the other quadrangles, where there is an entire
lack of any rock that would serve as a key rock and where,
in fact, the stratigraphic position of none of the coals, lime-
stones, shales or sandstones can be determined by an exami-
nation of the rock stratum itself. Under these conditions,
with the second method it is possible to carry the structure
over larger areas within which it is not possible to recognize
the stratigraphic position of any outcropping rock. In a region
in which such rocks are the outcropping rocks, and where
almost none of the outcrops are in umweathered exposures,
even the second method may yield onlysqmgertain results. Over
21
large areas in the quadrangles mentioned in the preceding
paragraph just such conditions exist. Generally the presence
of the sandstones has to be assumed from the scattering sand-
stone fragments on the surface. Often, where the land is all
under cultivation the existence of stone fences or of small
stone piles in the fence corners has been the best evidence
obtainable of the presence and position of a sandstone. In
certain places some sandstone has been locally more resistant
than those above or below it, and its top can be traced around
the hill slope by following the top of the scattered boulders
that have been derived from it by weathering. In the rocks
of the lower Cdnemaugh, it will be noted that the distance
from the top of what appears to be the same sandstone in
adjacent sections down to the Upper Freeport coal varies so
greatly that even, though the top of such sandstone be traced
for several miles it is not sure how closely the underlying sur-
face to be contoured will follow the same levels. Some of the
difliculties of working out the structure are thus practically
stated so that too much confidence may not be placed in the
structure as shown. In general, the contour interval has been
so chosen that the limit of error will not be greater than the
contour interval. It is true that in many of the quadrangles
over considerable areas the limit of error is well within the
contour interval, but again, on the same quadrangles there
may be areas in which the limit of error is much greater. In
the latter cases it is usually planned to make the contour
lines broken or dotted.
“The Structure as Represented. On the map, is brought
together the structure, represented by contours, over a large
part of southwestern Pennsylvania.
“Probably never before has the detailed structure of so large
an area been accurately represented, certainly not in this
country. It therefore represents an opportunity for the study
of the folding of the earth’s surface under the conditions here
existing that it is hoped may be taken advantage of in the
future. _ \
“In drawing the structure of the large map, the Pittsburgh
coal was chosen as the horizon to be contoured rather than one
of the lower and more widespread horizons, because a lower
22
horizon would go below sea level in the southwest corner of
the State—a condition that when represented is always apt
to be misleading. In preparing the map the structure maps
as published or prepared were reduced to the scale of the new
map and the structure transferred. In several of the quad-
rangles the structure as originally drawn on the maps was on
the base of the Pittsburgh bed. In these cases the structure
was transferred without change. In other quadrangles various
horizons have been used to contour on. The Washington lime-
stone, Ames limestone, the Upper Freeport coal, the Middle
Kittanning coal, the Lower Kittanning/ coal, have all been
used. In these cases the distance was coni‘puted from the
Pittsburgh coal up or down to the layer actually contoured on
in any case. Usually the figures were taken in round numbers,
as 300 feet below the Pittsburgh coal to the,Ames limestone;
600 feet from the Pittsburgh coal to the Upper Freeport coal,
increasing to 750 feet at the east. To the Lower Freeport coal
50 feet additional were added, and to the Lower Kittanning
200 feet additional. By knowing the intervals from one coal
to another in any of the quadrangles and the assumed interval
from the Pittsburgh bed to one of the coals in each quadrangle,
the approximate elevation of any coal in the area may be
computed from the map.
“The following table will therefore enable anyone to com-
pute the actual elevation of the stratum in each quadrangle
that has been used to contour on, and by using the intervals
as given in the table of coals or the local descriptions, the
approximate elevation of any other coal or stratum may be
computed:
“TABLE GIVING STRATUM UPON WHICH OONTOURS HAVE BEEN
DRAWN IN THE FIELD NOTES OR DETAILED PUBLICATIONS,
AND THE ASSUMED DISTANCE FROM THE PITTSBURGH GOAL
TO THAT STRATUM.
Feet.
Newcastle quadrangle, Middle Kittanning, . . . . . . . . . . . . . . . . ——70()
Beaver quadrangle, Upper Freeport coal, . . . . . . . . . . . . . . .. -—550
(Ames limestone), . . . . I . . . . . . . . .' . . . . . . . . . . . . . . . . . . . —-—260
Sewickley quadrangle, Ames limestone, . . . . . . . . . . . . . . . . .. -—260
Burgettstown quadrangle, Pittsburgh coal, . . . . . . . . . . . . . . . . 0
Carnegie quadrangle, Pittsburgh coal, . . . . . . . . . . . . . . . . . . . . 0
23
Claysville quadrangle, Upper Washington limestone, . . . . . . +570
Amity quadrangle, Pittsburg coal, . . . . . . . . . . . . . . . . . . . . . . .. 0
Brownsville and Connellsville quadrangles, Pittsburgh coal, 0
Rogersville quadrangle, Pittsburgh coal, . . . . . . . . . . . . . . . . . . 0
Waynesburg quadrangle, Pittsburgh coal, . . . . . . . . . . . . . . .. 0
Masontown-Uniontown quadrangles, Pittsburgh coal, . . . . . . 0
Clarion quadrangle, Lower Kittanning coal, . . . . . . . . . . . . . . ——800
‘ Kittanning and Rural Valley quadrangles, Vanport lime-
stone, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ———850
Elders Ridge quadrangle, Upper Freeport coal, . . . . . . . . . . . -——700
Latrobe quadrangle, Pittsburgh coal, . . . . . . . . . . . . . . . . . . . . 0
Indiana quadrangle, Upper Freeport coal, . . . . . . . . . . . . . . . . -—-700
Punxsut/awney quadrangle, Upper Freeport coal, . . . . . . .. —700
Cunwensville and Houtzdale quadrangles, Lower Freeport
coal , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ——750
Barn'esboro- Patton quadrangles, Lower Freeport coal, . . . . -—750
Johnstown quadrangle, Lower Kittanning coal, . . . . . . . . .. ——850
Ebensburg quadrangle, Upper Freeport coal, . . . . . . . . . . . . . . -—750
“In the above table the minus sign indicates that the amount
given should be substiacted f; om the elevations given on the
contour map; the plus sign indicates that the amount should
be added.
“Without discussing the structural details, certain general
features are readily apparent and need only be referred to.
“First, there is the general nqrtheast-southeast trend of the
folds. While not nearly so straight as they have frequently
been represented, nevertheless, taking large distances, the
folds in this part of the State tend to have axes running about
N. 30° E. On the south line of the State the trend is more
nearly north, running from-N. 20° E. to N. 25° E. Toward
the northern part of the map there is marked bending to the
eastward. Had the map therefore been continued farther to
the north and east, the general trend would have been more to
the east, possibly as high as N. 45° E.
“In the second. place there is noted a marked change from
the closely folded anticlines and synclines of the southeast to
the open gentle folds of the northwest, until to the northwest
of Pittsburgh the structure is little more than an irregular,
very gentle slope in which some parts project very slightly
beyond adjacent parts. So gentle is much of the structure
at the northwest that, except for the spirit-leveled elevations
to which it was everywhere referred, it would hardly have been
? t
a
"'wb0<
v
3 J)
J )3"
a u‘.
a: a
2
u
24
possible to have detected any variations at all from a uniform
slope, and the structure might have been drawn in with a
ruler; and yet the work in oil and gas has shown that in many
cases even these slight irregularities in the slope seem to have
had a marked effect on the position of the oil and gas pools.
“In the third place it will be noted that the folds are, as it
were, but wrinkles on the surface of a broad syncline, of which‘
the axis runs southwest and northeast through Pittsburgh.
South of Pittsburgh this axis coincides with the axis on the
Ninevah syncline and farther north with the axis of the Fair-
mount syncline. Thus at the southeast the position of the
Pittsburgh coal is theoretically on the Dulany anticline, 4,200
feet above sea level; on the Fayette anticline 1,800 feet above
sea level; on the Belle Vernon anticline 1,050 feet above sea
level; on the Amity anticline, the same, and in the Ninevah
syncline it gets down to less than 100 feet above sea level. This
is possibly even better brought out by a line through Indiana.
Thus starting 10,000 feet above sea level in the southeast
corner of the Ebensburg quadrangle, the Pittsburgh coal even
in the Pavia syncline does not get below 4,200 feet above sea
level ; in the deep VVilmore basin to the northwest it gets down
to 1,700 feet: west of that is keeps above this elevation until
the Laurel Hill axis is crossed where it has a maximum eleva-
tion of 3,000 feet above tide, though to only 2,800 feet in the
line being followed. From the Laurel Hill anticline to Indiana
the synclines carry the coal below 2,000 feet, and the anticlines
raise it above 2,500 feet. The Latrobe syncline carries the coal
down to 1,700 feet at Indiana and still lower farther south.
The Elders Ridge syncline carries it down to 1,500 feet and
down to 1,100 feet farther south. The Greenville anticline
can only raise it to 1,600 feet in the line here followed, though
nearly 2,300 feet farther north, while in the Fairinount syn-
cline the Pittsburgh coal south of Kittanning is only 1,550
feet above tide.
“I n the fourth place it is to be noted that in the center of
the major synclinal axis there is a general rise of the structure
in the direction of the axes of folding to the northeast. Thus
in the axis of the major syncline it will be noted that in the
southwest corner of the State the Pittsburgh coal is almost
‘ u.
‘0" u
25
down to sea level—locally within 100 feet of it. Going toward
Pittsburgh the strata in the center of the basin rise as in
climbing toward the point of a spoon until at Pittsburgh the
coal of that name is 1,000 feet above sea level. Going north-
eastward the same rise continues until in the Clarion quad-
rangle in the lower part of the major basin, the Pittsburgh coal
is theoretically over 2,000 feet above sea level. If the Union-
town syncline be followed it will be found near Uniontown to
bring the Pittsburgh coal down to 550 feet above tide. At
Latrobe the coal is not below 700 feet; at Blairsville about
1,000 feet, at Indiana it is 1,700 feet above tide. This tendency
to rise to the northeast does not continue southeast of the
Chestnut Ridge, and in many parts of that area may be re-
versed. Thus in the Uniontown quadrangle the position of
the Pittsburgh coal on Chestnut Ridge is about 4,000 feet;
east of Latrobe less than 3,500 feet; east of Indiana only 2,500
feet, and but little higher east of Punxsutawney.
“In the first syncline east of Chestnut Ridge the Pittsburgh
coal is theoretically above 2,100 feet on the Uniontown sheet.
East of Indiana it is down to 1,900 feet, but on the Curwens-
ville sheet it ranges between 2,000 and 2,350 feet, so that the
theoretical strike follows the axis of the folds. The Laurel
Hill anticline east of the west wedge of the J ohnstown quad-
rangle has raised the Pittsburgh coal theoretically to 3,900
feet; in the northern part of the quadrangle it is down to 2,800
feet and at Coalport to 2,400 feet; eastward on the Houtzdale
quadrangle it raises to 2,900 feet again. In the J ohnstown
syncline, and in the Bradley, Mud Lick and Houtzdale syn-
clines the coal keeps not far from 2,000 feet.
“Fifth, it emphasizes as has never been done before the undu-
lating character of the folds in the direction of the axes. No
such even-crested anticlines or even-bottomed troughs or ‘syn-
clines as have usually been pictured have been found to exist
in the area covered by the map. Instead the synclines appear
to be a series of elongated pr oval or spoon-shaped basins
separated by relatively high divides or buckles; and the anti-
clines consist of elongated or oval domes or crests separated
by low ‘sags’ as they may be called. A study of the relative
position of these basins and crests brings out some interesting
26
points. In the U niontown-Connellsville quadrangles the basins
and crests are set in alternate arrangement, while in Cambria
county they are opposite. Thus, for examaple, the Uniontown
basin is not opposite the highest part of the crests of the
adjoining anticlines, but opposite the sags of those anticlines,
and mice 'L‘é’l'Stt. In Cambria county, on the other hand, it will
be noted that the highest part of the Ebensburg anticline is
almost exactly between the lowest parts of the Wilmore and
Johnstown basins adjoining it’ on either side. This is even
more strikingly shown in the Latrobe quadrangle where domes
in Fayette and Chestnut ridges and basins in the Greensburg
and Latrobe synclines all fall in a line nearly normal to the
strike. The same thing is true in the Roaring Run anticline,
Elders Ridge syncline and Jacksonville anticline. On the whole
the opposite arrangement appears to be more common than
the alternative, though not enough so as to be made the basis
of a theory in the matter. ln the case of the Latrobe quad-
rangle a line lying nearly normal to the structure through the
points of maximum folding south and west of Latrobe, from
the southeast corner of the quadrangle to the Greensburg syn-
cline, would cross contour lines to the extent of 5,400 feet;
one through the maximum folding south of Blairsville would
cross 5,150 feet, while through the nodes between, a line would
cross only 4,150 feet. Other cases are even more striking. A
nearly east and west line a little north of J ohnstown in cross-
ing from the Wilmore syncline to the Laurel Hill anticline,
would climb up 2,950 feet and down 750 feet or a total of 3,700
A parallel line through Ebensburg would climb up 900 feet
and down not at all, making a total of 900 feet.
“Unfortunately the areas not yet mapped prevent carrying
this study out broadly. It should be noted, however, that
in the cases cited that the lines passing over the greater
amounts of ascent and descent in the structure are not propor-
tionately longer than the other lines. The difference is made
up in the difference in the steepness of the structural slope. Now
it is a well known fact that a highly convex arch is longer than
a lower arch of the same span. It would therefore appear that
along certain lines transverse to the folding any selected rock
stratum as folded'ri's longer across the areas of maximum fold-
I.
I
27
ing than the same rock is along other selected lines or what
might be called nodal lines as they pass through the nodes of
these undulating axes. This difference is probably not large.
Calculation of the length of the Upper Freeport coal over the
Chestnut Ridge anticline on a line southeast from Punxsu-
tawney, as compared to the cord of the same arch, showed
a difference of less than 5 feet, notwithstanding the rise of the
arch at the center is 750 feet above the cord. The calculations
in question seem to show that the shortening of the rocks due
to folding in a line passing from the Allegheny Front north-
westward through Punxsutawney was much smaller than would
have been anticipated—not over 30 feet. Further south where
the folding is more intense it would be much more. Time does
not permit the following of the subject further at this time
as the whole subject of the mechanics of mountain-making soo'
becomes involved.
“Another question is raised by observing these nodal lines
and lines of maximum folding. Have there been axes of cross-
folding action? This too will be passed at this time. It is
probable that the completion of the structure of Somerset
county and of the breaks existing within the area already
enclosed will be necessary before some of these questions can
be examined with any satisfaction.”
Horizontal Sections. In addition to the delineation of struct-
ure by contour lines, so well described by Dr. Ashley, it has
been thought wise to accompany this map with a number of
sections. These sections are constructed on a horizontal scale
of l-62,500 of Nature, 4 times that of the general map. The
vertical scale of these sections is 1-12,000 of Nature. It will
be noted that the horizontal scale is that of the published
topographic maps, and therefore the relations of the geology
to the surface structure can be readily determined by com-
paring these detailed sections with the topographic maps.
There are 7 of these detailed sections.
( 1) A section extending from a point on the southern line
on the Uniontown quadrangle, latitude 39° 45’, longitude 79°
35', extending northward across the Uniontown and Connells-
ville quadrangles to latitude 40° 15’. Thence eastward 10’ to
longitude 7 9° 25’, a point on the southern side of the Latrobe
28
quadrangle. From this point the section extends due north
across the Latrobe, Elders Ridge, Rural Valley, and Clarion
quadrangles, to the northern edge of the map in latitude 41°
. 15’, longitude 79° 25".
- (2) A section parallel tov the preceding extending from a
- point on the southern line of the Rogersville quadrangle in
latitude 339° 45’, longitude 80° 25’, extending due north across
the ' Rogersville, Glaysville, Burgettstown and Beaver quad-
rangles, to latitude 40° 45'.
(3) A section extending from a point on the eastern line
of the Uniontown quadrangle, latitude 39° 50’, longitude 79°
30’, and extending due west across the Uniontown, Masontown,
Waynesburg, and B-ogersville quadrangles to longitude 80° '30’.
(4) A section extending from the eastern line of the ‘Con '
nellsville quadrangle, latitude 40° 10’, longitude‘ 79° 30’, and
extending due west across the Gonnellsville, Brownsville,
Amity and Claysville quadranglesto'longitude 80° 30'.
(5) A section extendingfrom the northeast corner of the
Indiana quadrangle, longitude 79° 00’, latitude 40° '45’, and
extending thence due west along the northern line of the In-
diana, Elders Ridge, Freeport, New Kensington, Sewickley
and Beaver quadrangles to longitude 80° 30’. D
(6) A section beginning at the southeast corner of ‘the
Uniontown quadrangle, longitude 79° 30,, latitude 39° .45’, and
extending thence northwesterly "across the Uniontown, Browns-
ville, Carnegie and Beaver quadrangles to longitude 80° 30’,
latitude 40° 45’. ‘ , >
(7) A section extending from the southwest corner of the
Masontown quadrangle, longitude 80° 00’, latitude 39° 45', and
extending-thence northeasterly across the Masontown, Gon-
nellsville, Latrobe and Indiana quadrangles to longitude 79°
00’, latitude 40° 45’. . ‘
It is believed that these detailed sections will be of very
great value .to all students of the geology of the region.
The importance of structure in connection with the accumu-
lation into paying quantities of petroleum and natural gas
cannot be over-estimated, and the direction and-character of
the various anticlinal and synclinal axes shown on the struct-
ure map, and by the detailed sections, cannot but be of interest
.29
in this connection. It is realized, of course, that the structure
as laid down on the horizon of the Pittsburgh coal does not
entirely coincide with the structure on the producing sands
found hundreds of feet beneath vit. This difference in the
structure of the deeper sands is not only due to local varia-
tions in the thickness of the intervening formations, but is
a necessary result of the nonconformity at the base of the
Pottsville before referred to. Owing, however, to the want of
continuity in the oil‘ sands over the portion of southwestern
Pennsylvania embraced by the map, it is not practicable to
depict the structure at the horizon of any one sand over so
“ ‘large an area. The relation and connection of the various oil
and gas fields and pools to the structure is, however, very
striking, as will be brought out in a map on which work is
' a now in progress.
(30)
REPORT NO.2 PLATE NO.1

T_OPO§BAPHIC AND GEOLOGIC SURVEY OF PENNSYLVANIA _ _
80°30, 79°00’ 78°30’
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AREAL GEOLOGY
SOUTHWESTERN PENNSYLVANIA



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TOPOGRAPHIO AND GEOLOGIC SURVEY OF PENNSYLVAN‘A REPORT No.2 PLATE No.2
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STRUCTURAFL GEOLOGY
SOUTHWESTERN PENNSYLVANIA
STRUCTURE ON HORIZON OF PITTSBURGH COAL
LEGEND
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PERMIAN MDNONGAHELA CONEMAUGH ALLEGHENY POTTSVLLE Pocono DEVONIAN HELDEREERG MEDWA ORDOVYCIAN
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TOPOGRAPHIG AND GEOLOGIC suave-y OF PENNSYLVANIA PLATE N0.Ill
so‘oo' A 79‘00'
I
I
NESHANNOCK MERGER HILLIARDS FOXBORG CLARION BROOKVILLE
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|
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| FOL. 14s FOL-12! , FOL. 82 ‘
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D L A B L
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INDEX MAP SHOWING
LOCATION OF HORIZONTAL SECTIONS

TOPOGRAPHIC AND

GEOLOQIO $URVEY OF PENNSYLVANIA










UNIONTOWN QUADRANGLE









YOUGHIOGHENY RIVER

I
L AT 4000'
CONNELLSVILLE
CONNEL LSVILL E
F YEBTE CO-
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TMORELAND CO.


QUADRANGLE
PITTSBURGH COAL
REPORT NO- 2.


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PLATE ~o.g_|

























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N I MONONGAHELA CONEMAUGH ALLEGHENY POTTSVILLE P°°°~° PERM'AN PERM‘AN

UNIONTOWN QUADRANGLE
BROWNSVILLE QUADRANGLE
GEOLOGIC szcwou (B—B) .
THROUGH
BEAVER, CARNEGIE, BROWNSVILLE s. UNJONTOWN
QUADRANGLES, PENNSYLVANIA.

PITTSBURG H O OAL
HORIZONTAL SCALE 1 IT062,500
VERTICAL ~~ ITO/2,000




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MONONGAHELA RIVER
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REPORT NO- 2




































TOPOGRAPHIC AND cEoLomc SURVEY or PENNSYLVANIA PLATE "an
MASONTOWN QUADRANGLE m _ CONNELLSVIL LE QUADRANGLE
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n- w < ----_
REPORT NO- 2
























TOPOGRAPHIC AND GEOLOGIC SURVEY OF PENNSYLVANIA 1 __ PLATE Nam
ROGERSVILLE QUADRANGLE CLAYSVILLE QUADRANGLE
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GREENE WASFHNGTON MONONGAHELA QONL'MAUGH ALLEGHINY GREENE WASHINGTON MONONGAHELA CON!‘ MAUGH ALLEGHENY
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SEA LEVEL


























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PERMIAN
MISSISSIPPIAN
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REPORT NO-Z

TOPOGRAPHIC AND GEOLOGIO SURVEY OF PENNSYLVANIA PLATE Nam ’
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BEAVER QUADRANGLE ‘3 NEW KENSINGTON QUADRANQLE
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MISGISSIPPIAN MISSISSIpPIAN

REPORT NO. 2
PLATE NO.1Y

ToPogggm-uc AND GEOLOGIC. SURVEY OF PENN8YLVAN|A

CLAYSVILLE QUADRANGLE AMITY QUADRANGLE
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‘ THROUGH
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QUADRANGLES, PENNSYLVANIA.
'\,/\ L‘ w a HORIZONTAL SCALE’- !1'062,500
WASHINGTON 60-
MONONGAHELA RIVER
WESTMORELAND 00
YOUGHIOHENY RIVER
TARRS











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PERMiAN MISSISSIPPI/QM
VERTICAL - - I TO 12,000
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. ‘ REPORT No.2
I . PLATE NO-X
I
TOPOGIRAPHIC AN'IQTYGEOLOGIC SURVEY OF PENNSYLVANIA
WAYNESBURG QUADRANGLE.
ROGERSVILLE QUADRANGLE
























' LATIB °.so’ ' "m LAT. 39‘250'
LIBIVI; 23:35.2’ Ca . Ccm L oNc. air/5' C" 0" L_..___:Icm ‘- ONG- 9000"" L________cw
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n. HORIZONTAL scALE: ITo 62,500
VERTICAL -- ITo 12,000


SEA LEVEL
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LAT 9 so I l l: C, 0,“, Cm 6"‘ I" D l LONG.79°50'




6"’ cm C ‘* GP” cm L ONG- 79°45’ { c""______ w ._ -__._____ ~w——~
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