Warren. - Area, 910 square miles: population in 1880, 27,981. This
county is square, 36 ½ miles long on the New York State line and 26
½ miles wide on the Crawford and Mckean County lines. The Allegheny
River reenters the State at its north-east corner; runs south and
west to Warren, where the Conewango River comes in from the north;
keeps on 7 miles further west to Irvineton, where the Brokenstraw
comes in from the north-west; then 14 miles south-west to Tidioute
and Triumph; then 4 miles to the Forest County line. The Oil Creek
waters drain out at its south-west corner. The most remarkable feature
in the drainage of this county is the heading of Tionesta Creek on
the highest land overlooking the Allegheny River in Watson Township;
* whence it flows in a direction opposite to the course of the river,
north-east, to Cranberry Swamp (6 miles south-east of Warren). Here
it turns and flows south 6 miles to Sheffield, where it receives its
south branch coming from the south, and then the combined streams
flow south and south-west through Forest County to the Allegheny River.
There is no way of accounting for this remarkable topography in Meade,
Cherry Grove, Sheffield, and parts of Kinzua and Pleasant Townships,
but by accepting Mr. Carll’s conclusion that in the ages before the
invasion of the northern ice the drainage of the Tionesta was northward
to Warren, and that the reversal of the drainage to its present
southward direction was caused by a dam of glacial drift being thrown
across the ancient valley between the Cranberry Swamp and Warren.
In fact the oil wells at Clarendon have gone through 250` of drift
before reaching the bed rock of the ancient valley. Similar facts
observed throughout the upper Allegheny River region in Pennsylvania
and New York form a body of evidence that the whole rainfall north
of Tidioute previous to the ice age passed northward into the eastern
end of Lake Erie.
All the highest highlands of the southern half of the
county consist of massive coarse Olean conglomerate, sloping
gently south-westward at a rate of 16 feet per mile;=
consequently the only coal beds in the county are the Sharon and perhaps
Scrubgrass coals, and nowhere of much importance. At Quaker Hill,
in the south-west corner of Elk Township, north-east of Warren, the
Sharon bed (2`) has furnished a good deal of coal for the neighborhood.
The Olean conglomerate caps the high ridges north of the Allegheny
and Brokenstraw, making a great show in cliffs and gigantic fallen
blocks, especially at Garland Station on the Philadelphia and Erie
railroad. The outcrops of the Sub-olean conglomerate form cliffs
and steep bluffs along all the valleys and ravines; the lower slopes
consist of Crawford shales, in the upper part, and the Venango oil
sand group (300` thick) in the lower part. The underlying Chemung
flags are above water in the Allegheny River valley, from the State
line up to Kinzua in the Conewango river valley, from the State line
up to within 5 miles of Warren, in the Stillwater Creek valley from
the State line up to Sugar Grove, in the Little Brokenstraw valley,
from the State line down to Lottsville.
The Shenango shales under the Olean conglomerate mark the
end of a geological age by the fact that they vary in thickness from
60` to 30`, and the Olean above them seems in some places not only
to cut them out entirely but even to descend so as to take the place
of the Sub-Olean conglomerate which underlies them; to say nothing
of the fact that in Eastern Pennsylvania they are represented by 3000`
of Mauch Chunk red shale (XI) or perhaps by the uppermost strata of
the Pocono formation No. X. North-west of the Allegheny River they
are almost uniformly 50` thick; but south-east of the river they thicken
to 100` at Sheffield and 120` or more at Brookstone; and on the Clarion
to 150`.
The Sub-Olean conglomerate (X) marked by its flat pebbles
ought to be a key rock to the oil drillers; but they have paid as
yet no attention to it. The three Oil Sands of Venango County
(already described on page-above) are in full forces along the river
up as high as Tidioute. Here the highest summits are capped by Olean
conglomerate and Sharon shales, and (in Deerfield) by Kinzua sandstone
(middle XII.); the general highland by Shenango shales and
Sub-Olean conglomerate; and along the river bluffs run the
three Mountain Sands of Oil Creek. The lowest or Third Mountain
sand (Pithole grit) loses its individuality (turning into a shaley
flaggy series, no one sandy member of which can be followed with any
certainty) as it slowly rises along the river from Tidioute towards
Warren. The First Oil sand also outcrops along the hill-side,
but becomes less well defined going towards Brokenstraw Township.
The Second Oil sand at Triumph is divided into two (the lower
one at Tidioute just below water level) but loses its character and
passes into shales under the high land west of the river. The Third
Oil sand, 120` thick at Triumph dwindles to 30` at Tidioute, and
in the next three miles north-eastward is indistinguishable as a separate
stratum from the super and subjacent shales. The sandstone layers
in the hill-sides at Warren therefore cannot be identified with the
three Oil sands as has been often asserted; and furthermore
no special thickness can be assigned to the interval between the Venango
Oil Sand group and that Warren Oil Sand group which
has yielded oil beneath Conewango creek. Nor do these Warren sands
extend southward beneath the Venango sands; for the borings from Warren
down to Triumph show nothing of the kind beneath the Venango Third
sand; neither do the Bradford oil sands, as the Clapp well No.1
(bored in 1882) and the Fagundus well No.37 (deepened from the Third
sand downwards in 1882) prove. The Clapp well, 3 miles west of the
river and 3 miles north of the Forest line (2464` deep) went to 2550`
beneath the Olean conglomerate; and the Fagundus well (2700`
deep) to 2700` beneath it, without striking a single well-defined
sand referable to either the Warren or Bradford rocks in the 1600
feet of shales underlying the Venango Third Sand. The Warren oil sand
rocks are as specially and peculiarly a feature of Warren County as
the Bradford oil rocks are a unique feature of the geology of McKean
County. Gardner’s rock is a picturesque outlier of horizontal Olean
conglomerate (at "the Pass" S.E. corner of Elk Township) from the
bottom layer of which blocks (30` high, 40` wide and 70` long) have
detached themselves and slidden down the slopes of Hatch’s run; top
of rock at summit 2080` A.T.; top of Gardner’s rock 2030` A.T.; Allegheny
River at mouth of Conewango Creek 1177` A.T. The Wolf Den is another
fine object. The Beatty well No. 1 at East Warren (or Glade City,)
the first paying well in measures lower than the three Venango Oil
Sands, was bored in March 1875; well mouth 1217` A.T.; valley drift
90`; oil and gas got from 620` down to 629`; production 5 bbls.
*
Developments naturally spread from this as a center; North Warren
was opened on one side and Stoneham on the other. The most astonishing
oil development ever witnessed in Pennsylvania commenced with the
Jamestown Oil Co.’s well, called the "Mystery" from the precautions
successfully taken to conceal its first yield from the public until
May 18,1882, when the plug was removed and 1100 bbls. a day flowed;
it was drilled a little deeper and yielded June 13, 2000 bbls. By
the end of August this new Cherry Grove or Garfield district was pouring
upon the oil market 40,000 bbls. per day from 69 wells completed to
August 1, and many more bored that month. Of 405 wells commenced in
seven months (May-November, 1882) 383 were productive and only 22
dry. But each flowing well fell off rapidly in its daily yield; for
example, the Sardine Co.’s well flowed its first six days 2000, 1128,
594, 444, 350, 274 bbls. The "Mystery" well, above mentioned (its
mouth 1805` A.T., struck oil at 1630`) or 175` above tide level; passing
the Clarendon oil sand at 1345` or 460` above tide level, with
no show of oil. The order of Warren oil rocks is thus given by Mr.
Carll: North Warren oil shales say 1200` beneath the Olean conglomerate;
Warren "third sand" 1325`; Stoneham wells 1400` (gas horizon in N.
Warren); and a little oil in North Warren from strata 1650` beneath
the O.C. (For innumerable details and discussions see Report I4,
1883.)
* Cobham P.O. is 1140` A.T. Road forks to Warren 1790`. Head of west
branch of Hickory Creek at bridge 1555`. Sheffield depot 1344`.
= Base of
Olean conglomerate in Glade Township 1996`; on the Forest County line
west of the river 1550` A.T. (See Report I4, p. 186.)
* For a map of the Warren wells see preface to Report I4, pp. xvi-xix.
From: A geological hand atlas of the sixty-seven
counties of Pennsylvania :embodying the results of the field work
of the survey, from 1874 to 1884. By J. P. Lesley. (Report of
progress (Geological Survey of Pennsylvania), v. X ) Harrisburg, PA
: Board of commissioners for the second geological survey, 1885.
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