xt7bcc0tqx99 https://exploreuk.uky.edu/dips/xt7bcc0tqx99/data/mets.xml Moore, Philip North, b. 1849. 1878 books b96-13-34908917 English Stereotyped for the Survey by Major, Johnston & Barrett, Yeoman Press, : Frankfort, Ky. : Contact the Special Collections Research Center for information regarding rights and use of this collection. Geology Kentucky. Coal Kentucky. On the geology of the region adjacent to the eastern border of the western coal field : from the Louisville, Paducah and Southwestern railway to the Ohio River / by P.N. Moore. text On the geology of the region adjacent to the eastern border of the western coal field : from the Louisville, Paducah and Southwestern railway to the Ohio River / by P.N. Moore. 1878 2002 true xt7bcc0tqx99 section xt7bcc0tqx99

GEOLOGICAL SURVEY OF KENTUCKY.

N. S. SHALER, DIRECTOR.

ON THE GEOLOGY

OF TH

REGION ADJACENT TO THE EASTERN BORDER

OF TM

WESTERN COAL FIELD,

FRM THE
LOUISVILLE, PADUCAH AND SOUTHWESTERN
RAILWAY TO THE OHIO RIVER.

BY P. N. MOORE.

PART XI. VOL. IV. SECOND SERIES.

SOTS TIXWon IR -I" BY JO.O By, UOYALAdAOB. -.
423 & 424

This page in the original text is blank.

ON THE GEOLOGY OF THE REGION ADJACENT TO
THE EASTERN BORDER OF THE WESTERN
COAL FIELD, FROM THE LOUISVILLE,
PADUCAH AND SOUTHWESTERN
RAILWAY TO THE OHIO RIVER.

The work of tracing the eastern outline of the western coal
field was performed by a party in charge of Mr. S. S. Lyon,
in the year 1859, while the former Geological Survey of the
State, under direction of Dr. D. D. Owen, was in progress, and
a report was published in volume IV, first series Kentucky
Geological Reports. A skeleton map, which was constructed
at the same time, has, however, never been published, but has
remained in the archives of the Survey to the present time.
The work by this party was, however, from necessity, done
in so rapid a manner that it could not be detailed. Mr. Lyon
himself states (vol. IV, p. 586) that a large portion of the
margin of the coal measures was only approximately deter-
mined.
The topographical work was confined to mapping some of
the principal roads near the coal field margin-some inside of
it and some beyond. The geological observations seem like-
wise not to have extended over an area of any great width,
nor to have embraced the country between the mapped roads.
For these reasons the Director of the Survey ordered the
re-survey of this area during the past season, extending the
examinations to the west within the coal field, in most cases
beyond the point where the Sub-carboniferous rocks disappear
beneath the drainage, and far enough to obtain some knowl-
edge of the position and character of the coals which are near
the margin.
The topographical party under Mr. W. B. Page extended
its operations as far to the west as the geological examina-
42S

4 REPORT ON THE GEOLOGY OF THE REGION ADJACENT TO

tions, mapping all the roads and principal streams. It is
owing to their work that the outline can be delineated with
any detail.
In speaking of the outline of the coal field in the following
pages, the word will be used to mean the line where the coal-
measure rocks first present anything like a connected body,
or beyond which they are the prevailing rocks.
The term must, of necessity, be used somewhat arbitrarily,
for the edge of the coal field presents an extremely broken
and irregular outline, being cut through by nearly every
stream and ravine, so as frequently to isolate large areas, or
leave them as tongues or outliers extending out over the
Sub-carboniferous rocks.
The outline or margin of the coal field, from the point south
of Leitchfield, Grayson county, whence it was followed south
to Green river, in the report, part I, volume II, second series
Kentucky Geological Reports, turns towards the west, crosses
the Louisville, Paducah and Southwestern Railroad about three
miles from Leitchfield; thence runs nearly parallel to the rail-
road, and not more than a half mile north of it, until a short
distance beyond Caneyville, where it turns to the north. The
Chester limestone is seen in the road about one half mile
north of Caneyville, while a short distance beyond nothing
but Sub-carboniferous rocks occur.
From Caneyville to the Falls of Rough creek the outline
runs a little to the west of the Bowling Green and Cloverport
road. Its distance from this road varies somewhat, but it does
not cross the road, unless, perhaps, at one place on a high
dividing ridge, and this even is not certain.
It is broken by the valley of Short creek, which runs
entirely in Sub-carboniferous rocks from head to mouth, and
again by Rough creek.
The triangular area between this road, Short and Rough
creeks, is entirely detached and surrounded by Sub-carbonifer-
ous rocks; but it occurs in the direction of the principal line
of outcrop, and, by position, belongs properly to the main
body of the coal measures.
426

THE EASTERN BORDER OF THE WESTERN COAL FIELD.

Near the Falls of Rough the coal measures cap the ridge
to the west of, and but a short distance from, Pleasant run.
Crossing Rough creek, they are first found in the Cloverport
road, capping the ridge west of Rock Lick creek. From here
the outline still follows closely the Cloverport road, crossing
it occasionally, and often cut by the streams which the road
crosses, until within a few miles of Cloverport, where it turns
toward the northwest, crosses Tar Fork and a number of its
branches, and reaches the Ohio river between Hawesville and
Cloverport.
There are a number of outliers a considerable distance to
the east of the margin as just described, but they are mostly
entirely isolated, and of small extent. They usually consist
of detached knobs or high dividing ridges between streams,
capped with a small thickness of wasted coal-measure rocks.
They do not, so far as known, carry any coal, although a few
of them apparently rise high enough to hold the lowest coal;
but it is probable that, even if present, the coal will be found
badly weathered and worthless, owing to the slight covering
above it, and the effects of exposure on all sides.
Such outliers occur on the ridge between the waters of
Tewells and Long Lick creeks, between the branches of
Rough creek and Clover Fork, at Sand or Pine Knob, near
Eskridge's Ferry, and also south of Rough creek, between
that stream and Short creek.
The Sub-carboniferous rocks are found above drainage
much further to the west than the outline above described.
Nearly all of the principal streams shown in the accompany-
ing map, by Mr. Page, except in the central and western por-
tion of Hancock county, cut their channels in these rocks.
Near the Ohio river the Chester limestone is last seen im-
mediately below, and in contact with, the Conglomerate sand-
stone, about one mile above Hawesville. Indian creek runs
in Sub-carboniferous rocks from head to mouth; but Lead
creek, which is next below, and not far distant, does not cut
below the Conglomerate. The different branches of Tar Fork
all run in the Sub-carboniferous rocks.
427

6 REPORT ON THE GEOLOGY OF THE REGION ADJACENT TO

On Sulphur Fork of Blackford creek, at Patesville, it is
stated that the Chester limestone was found a few feet be-
low the bed of the creek, when digging a water-pit for a saw-
mill; elsewhere it is not seen on this stream. It is found in
all the head branches of Panther creek, and extends in the
main stream nearly a mile west of the Cloverport and Fords-
ville road before it passes below the drainage.
Crossing the divide to the waters of Adams' Fork, a branch
of Rough creek, the Chester limestone is found near the heads
of the main branches, except Middle Fork, which does not cut
it until within about one mile and a half of Fordsville, where
the top of it is exposed. It is also seen just below Fordsville,
but disappears again, and is not exposed for so'me distance.
No exposures of the Chester limestone have been found
west of Fordsville and Middle Fork.
After its junction with the Middle Fork, the main branch
of Adams' Fork runs in this limestone, to its mouth.
The branches of Rough creek from the north, and those
emptying above Adams' Fork, all run in the Chester rocks
nearly from head to mouth.
Rough creek itself has cut a wide valley in the Sub-carbon-
iferous rocks for its whole length, in the region under discus-
sion. This is owing to an anticlinal or uplift in the strata,
by which the Chester rocks have been raised to the present
surface far inside of the coal field. The axis of the anticli-
nal is followed pretty closely by Rough creek, within the area
covered by this report, although occasionally the creek runs
in the edge of the coal measures at one side of the Chester
rocks exposed. This is due to the fact that the disturbed and
folded rocks are most readily worn away by the action of run-
ning water, and thus afford the easiest channel for a stream
to flow along. The anticlinal, therefore, has probably been
the agent which has directed Rough creek into its present
course.
This anticlinal is the most important geological disturbance
of this region. It completely divides the region under dis-
cussion into two parts, as the coal-measure rocks at no point
428

THE EASTERN BORDER OF THE WESTERN COAL FIELD.

extend across it. The rocks dip away from Rough creek in
both directions, sometimes quite regularly and sometimes
broken by small faults.
The writer is informed by Mr. Norwood that, shortly after
passing to the west of this region, Rough creek leaves the
line of the anticlinal, which extends westward through Ohio
county some distance to the north of Rough creek, and finally
crosses Green river into Webster county. For the particulars
of its course the reader is referred to the report of Mr. Nor-
wood upon the geology of Ohio county. Enough has been
stated here to show that this is a geological feature of more
than local interest, if not the most important disturbance in
the western coal field.
South of Rough creek all of its branches, as far west as,
and including, Caney creek, have cut down to the Chester
rocks. Near the railroad, on Caney creek, the rocks are so
covered that it is difficult to tell at what geological level it
does run, but it is not far above the Chester limestone, if
any; and before it reaches its mouth, Caney creek has cut
nearly one hundred feet down into the Chester rocks. Along
the railroad, as shown by Mr. Norwood's section in volume
I, second series Kentucky Geological Reports, the Chester
limestone is found a few feet above the creek, until beyond
Caneyville.
Between the railroad and Rough creek, Caney creek and
the Bowling Green and Cloverport road, the coal measures
cap the ridge, and toward the railroad cover most of the sur-
face; but on the Rough creek slope they extend only over a
small area on the tops of the ridges.

GENERAL GEOLOGY.
In the region under consideration there are exposed only
the rocks of the Carboniferous system, including:
Carboniferous, - - Coal Measures.
Sub-carboniferous, - f Chester Group.
St. Louis Group.
429

8 REPORT ON THE GEOLOGY OF THE REGION ADJACENT To

The characteristics of these different divisions have been
so fully and recently described in the reports of the Geolog-
ical Survey, that it is not considered necessary here to repeat
them. They will be discussed here in an ascending order.

THE ST. LOUIS GROUP.
The limestone of this group, called by Mr. Lyon, in his
report (volume IV, first series Kentucky Geological Reports),
"the cavernous member of the Sub-carboniferous limestone,"
is exposed only in the eastern portion of the region under
discussion, where it is cut into by the streams, but not to any
great depth. It is seen on Little' Clifty creek and on Rough
creek, near the mouth of Little Clifty. It also probably
occurs on Short creek, its presence being indicated by the
topography; but the region has not yet been examined in
sufficient detail to determine with certainty if this be the
case.
North of Rough creek, and as far west as the Falls of
Rough, most of the streams and their branches run in the
upper part of the St. Louis limestone. This is also true of
the creeks flowing into the Ohio river as far west as Clover
and Tar Forks, which empty at Cloverport.
In none of these cases, as already stated, is a considerable
thickness of the rocks of the St. Louis Group exposed, so
that it is practically of small importance. But a short dis-
tance to the east, in Breckinridge county, the St. Louis lime-
stone is the most prominent member of the rock series.
The thickness exposed in the region covered by this re-
port is so small, that, from natural sections alone, little could
be known in regard to this limestone; but in the vicinity
of Cloverport, during the oil excitement some twelve years
since, numerous wells were sunk in search of oil, which pen-
etrated deep into the St. Louis rocks. Of these, unfort-
unately, the records of only two have been obtained. It has
been impossible, though diligent efforts have been made, to
find any trace of the others, as the individuals who sank the
wells and kept the records, if any were taken, have left the
430

THE EASTERN BORDER OF THE WESTERN COAL FIELD.

region, and no trace of them can be found. This is greatly
to be regretted, as the records of all these wells would furnish
valuable information in regard to the stratification below the
present drainage surface of the country, which can be ob-
tairned in no other way.
Sections obtained by boring, unless made for the express
purpose of ascertaining the character of the rocks, are always
liable to a certain amount of error from the difficulty of recog-
nizing the material passed through by the drill. This liability
to error is greatest where passing through thin strata, as the
line of transition from one to the other is not easily deter-
mined, owing to the mixing of the pulverized material by
the drill. When these allowances are made, however, these
records are of great value.
The two following sections are the records of wells sunk
by the Breckinridge Petroleum Company, and were kindly
furnished for publication by Mr. E. D. Tyler, of Louisville.
They were both sunk in Breckinridge county, on the waters
of Tar Fork, and the starting point in both cases was near
the base of the Chester Group. The records are given as
reported, although in some cases slightly altered in phraseol-
ogy, and abbreviated. The remarks in parentheses are by
the writer:
THE NEWTON WELL, HONEY LOCUST BRANCH OF TAR FORK.
Thickness, Total
feet. depth.

Soil........7........ .. 7
Sandstone...... .. .. . .. .. . .. . .. .. .. 2 9
Limestone... .. 19
Shales and thin sandstones.30 49
Sandstone...... .. .. .. . .. .. .. .. .. .. . 24 73
Limestone. . .. .. .. .. . 9 82
Slate and soapstone" (shale) ...... ............. . 41 123
Limestone...... .. .. .. .. . .. .. .. .. .. . 33 i56
"Slate and soapstone" (shale) ...... . . . ....... 23 179
Limestone.... . 15 194
Sandstone.... 3 197

It is stated by Mr. J. T. Goff, of Cloverport, that this well
was afterwards sunk to a total depth of nearly 300 feet; but
no records of it have been found, other than as above given.
431

TO REPORT ON THE GEOLOGY OF THE REGION ADJACENT TO

THE GABBERT

WELL, TAR FORK, ABOUT ONE
SPRINGS.

MILE BELOW TAR

Limestone ...............
Shale le................
Limestone ...............
Shale le................
Limestones.t e............
"iRed sandstone" ............
Hard shale ...............
Limestone. .
Hard shale ...............
Limestone .
Shale.. .. .
Limestones.t e............
Sandstone . .
Limestones.t e............
Shale .
Limestones.t e............
Shale. .
Limestones.t e............
Shale. .
Limestone. .
Shale .
Limestone. .
Hard grey granite" (This is evidently a
ably a stratum of flinty limestone) ....
Limestone . .
" Limestone and sandstone" .
Limestone. .
Shale. .
Sandstone . .
Limestone ...............
Sandstones.t e............
Limestone . .
Sandstone... .. . .. . . .. . . .
Limestones.t e............
Sandstones.t e............
Limestone . .
Sandstone . .
Limestones.t e............
Sandstone . .
I.imestone.. .............
Shale .
Limestone . .
Shale. .

In the above record there is evidently a serious mistake in

the stratum recorded as "granite," for there is certainly no

such rock in this region. It is probable that it is a stratum

of unusually hard limestone, which the person in charge of the

well dignified with the name of granite.

If the above records are to be depended upon, they prove

that the St. Louis Group, instead of showing massive, homo-

432

Thicknes,
feet.

J0
3
42
50
37
10
15
23
15
30
so
10
87
2
21

4
3
9'

10
38
47
6
6
7
3
7
6
2
S
2
38

7
3
13
27
9
30

.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .

.. .
.. .
mistake.
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
. .
.. .

. .
.. .
.. .
.. .

Total
depth.

so
13
55
'0S
142
IS2
67
I90
205
235
245
332
334
355
300
371
378
391
392
396
399
490

500
538
585
6os
607
614
6X7
624
630
632
637
639
677
678
685
688
701
728
737
767

.. .
.. .
.. .
.. .

.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. . .
.. .
.. .
.. . .
z Z

Z Z Z

It is prob
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .
.. .

THE EASTERN BORDER OF THE WESTERN COAL FIELD. I I

geneous character, which it possesses further south and south-
east, is here formed of limestones interstratified with numerous
thin beds of shale and sandstone, and nowhere shows an un-
broken limestone of more than i5o feet thickness. For the
present, and until this group can be studied in more detail in
I3reckinridge and Meade counties, to the east of this region,
this conclusion must be regarded as tentative, as it indicates
a marked change from the character of the group as known
at other places. Dr. Owen, however, in volume II, first series
Kentucky Geological Reports, page 92, calls attention to this
same feature in Breckinridge and Meade counties.

'rHE CHESTER GROUP.
This group retains throughout the characteristics described
in the previous reports of the Geological Survey by Mr. Nor-
wood and the writer.
It consists of sandstones, limestones, shales, and marly
shales in great variety, both as to thickness and order or
position. The strata which compose it are very changeable
and uncertain in their occurrence-no one stratum, except
perhaps the Big Clifty sandstone, which marks the base of
the series, seeming to be persistent over any wide area.
For this reason no general section of the members of this
group can be given which will be more than locally accurate,
and none has been attempted. In a general way the rocks
retain the character shown in the sections 6f Mr. Norwood's
report along the railroad, and in the sections for the region
south of Leitchfield and Grayson Springs. (Part II, volume
11, second series Kentucky Geological Reports.) There is
a great prevalence, especially toward the upper part of the
series, of thin-bedded and shaly rocks, differing from the more
massive character which the members of this group present
further south, on Green river.
In the southern part of this region, along the railroad and
for a short distance to the north, the sections above referred
to, which have heretofore been published, illustrate the char-
acter of the stratification. The shales, marly shales,. and
VOL IV.-28 433

12 REPORT ON THE GEOLOGY OF THE REGION ADJACENT TO

marls are the most abundant rocks. Further north, in the
valley of Rough creek, on both sides of that stream, these
rocks are not so conspicuous, and where present are thin;
and we have a greater prevalence of thin limestones and
sandstones.
Still further north, in the immediate drainage of the Ohio
river, the shales and marly shales are again found abundant,
and of considerable thickness; in fact, they are the most con-
spicuous members of the series in this vicinity.
The following section, near the Bowling Green road, just
after the crossing of Tar Fork south of Cloverport, is fairly
typical of the upper portion of the Chester Group, and shows
the great abundance of these shaly rocks:
SECTON.
Top of hill.
Covered space; wasted coal-measure sandstones......... . .. . . 50 feet.
Limestone... .. .. . .. .. .. .. .. . .. .. .. .. .. .. 25
Shale. 15
Thin imestones.; I
Shale, upper part mary....... .. .. .. .. . .. .. .. .. .. 8
Limestone, very silicious. to
Dark shale .I
Limestone. 4
Shale. 6
Green m ir dsle 14
Shale. 25
Covered space o "0
Sandstone .25"
Covered (probably sandstone).......... .. .. .. .. . .. . . IS
Limestone .5.............................. . 25
Covered, limestone seen at intervals......... .. .. .. . .. . . 45
Red and green marly shale....... . . . .. .... . . .4.. ... 4
Covered space............................. 25
Tar Fork.
High water mark of the Ohio river will probably come
within a few feet of the last exposure of marly shale in the
above section.
The heavy sandstone at the base of the Chester series,
which has been called by Mr. Norwood the Big Clifty sand-
stone, is persistent throughout this region; more so appa-
rently than any other stratum of the group. It is found from
40 to ioo feet in thickness, and is generally exposed where-
ever the streams have cut into the lower part of the series.
It is called by Mr. Lyon the "d Lower Tar Spring Sandstone."
It is noted for the great number of tar springs which issue
434

THE EASTERN BORDER OF THE WESTERN COAL FIELD. 13

from its base. It is the sandstone which occurs in such im-
posing exposures at the Tar Springs south of Cloverport, in
Breckinridge county. It is also the sandstone which is seen
on the Ohio river below Cloverport. It is here an excellent
building stone, and has, in former times, been extensively
quarried and shipped away. Part of the rock for the locks
on Green river was obtained here.
The great prevalence of tar springs issuing from this sand-
stone gave encouragement to the idea that oil would be found
in this region in large quantities; but beyond this single fact
there was nothing which points to any such conclusion.

THE LEITCHFIELD MARLS.
The green and red marly shales, containing a considerable
per centage of potash, which are found in the upper part of
the Chester Group, and which occur in such abundance in
the vicinity of Leitchfield, Grayson county, that they have
been called by the Director of the Survey the Leitchfield
Marls, extend over a large part of this region. They may
be said to follow the distribution of the shaly and thin-bedded
strata as already given. Near the railroad they are abun-
dant. In the central part of this region, on Rough creek and
its tributaries, they have not been so frequently seen, and
where they do occur, they are thin. Toward the Ohio river,
they are again abundant and of great thickness. On nearly
all of the branches of Tar and Clover Forks they are fre-
quently exposed. The section just given shows them occur-
ring at several different levels.
At a locality in the edge of Hancock county, about three
miles from Cloverport, known as the Buffalo Wallow, there is
a remarkable natural exposure of these marly shales, show-
ing a thickness of thirty feet or more. These shales are re-
ported to extend several miles to the south of this locality,
still retaining this thickness.
There is, therefore, in the aggregate, in this region, an
enormous quantity of these marly shales, lying close to the'
surface, and very accessible. It is greatly to be hoped that
435

14 REPORT ON THE GEOLOGY OF THE REGION ADJACENT TO

some economical process will ere long be discovered, by which
the potash, their valuable fertilizing ingredient, can be ren-
dered soluble, and therefore immediately available. When
this can be cheaply accomplished, these beds will be of the
greatest value to this country as a source from which to
draw the fertilizers which shall renew the worn tobacco lands.
They exist in such quantities, and are so accessible, that they
will cost but a trifle; and the only expenses attending their
use will be the transportation and preparation.

THE CHESTER COAL.
The thin coal in the Chester rocks, which is so generally
found in the region south of this, is also quite persistent here.
It has been seen at a number of places, and is reported at
many more.
Dr. Owen and Mr. Lesquereux, in volumes II and III, first
series Kentucky Geological Reports, refer to two coals in the
Sub-carboniferous rocks, and state that they are sometimes as
much as ten inches in thickness; but the writer has seen none
of more than three inches.
Although nowhere of economic value, very many attempts
have been made to work these coals, and even yet time and
money are occasionally wasted in digging into them at new-
ly-discovered out crops, in the vain hope of finding them of
workable thickness-a hope which, it is unnecessary to repeat,
will never be realized. It is useless to search for workable
coal in the Chester rocks.

THE COAL MEASURES.
Within the area covered by this report, not including Han-
cock county, which will be discussed in a report devoted to the
whole county, we have shown a total of about i8o feet thick-
ness of coal measures, or perhaps 200 feet in some of the
highest knobs. A thickness of 150 to i8o feet is only at-
tained in the western part of this region, while to the east it
gradually decreases until only the tops of the hills are cov-
ered with a thin cap of wasted coal measures.
436

THE EASTERN BORDER OF THE WESTERN COAL FIELD. I5

The rocks vary so greatly in thickness, are so uncertain in
occurrence, and, withal, are so rarely well exposed, that it is
difficult to give a general section which will hold true over any
considerable area. Nevertheless, with the qualification that it
only shows the stratification in a very general way, the follow-
ing section is given:
CNLtAL SaClON.
i. Covered space, probably shales.:......... . 3o to 6o feet.
2. Coal.I........... .. .. .. . . . to 4"
3. Covered space, probably shale.o....... . . . s
4. Coal 4 to s1 inehm
5. Sandstone.I........................... o to 30
6. Shale....... . . o to 20
7. Coal.. otto4 4
8. Shale.i.
9. Coal . .12t026
lo. Sandstone and shale. .. .. .. .. .. to 30
Top of Chester limestone.
The plate of sections accompanying this report shows more
accurately the position and changes of these rocks.
It will be noted that no reference is made to the Conglom-
erate in the above general section. This rock is not recog-
nized in this region until near the Ohio river, in Hancock
county. At some places it seems to be represented by a
coarse, friable, micaceous sandstone; at others it is entirely
wanting; and we have the lowest coal resting almost imme-
diately upon the Chester limestone.
In the region to the south of this, which was embraced in
the report, part II, vol. II, second series Kentucky Geological
Reports, there is no rock which can be certainly identified
as the Conglomerate for a distance of several miles south
of the railroad. Its disappearance is nearly coincident with
the occurrence of the frequent small disturbances in, and the
sudden rise of, the Chester rocks toward the railroad. It
is possible that this may be due to the fact that, where the
Conglomerate is present, the faults and disturbances are not
noticed; but the fact remains. The Conglomerate is, there-
fore, wanting over nearly all the area in which the Chester
rocks are known to be considerably disturbed. Whether this
has any bearing upon the question of the age of these
disturbances, it is difficult to state. It certainly indicates a
437

i6 REPORT ON THE GEOLOGY OF THE REGION ADJACENT TO

cessation, over a large district, of the disturbed waters and
rushing currents which accompanied the deposition of the
Conglomerate, and a prevalence of more quiet conditions;
but whether this was accompanied by a greater submersion,
or a previous elevation of this region, is not yet certain.
This region, as is also true of other portions of the mar-
gin of the western coal field, shows a decided thinning of
the coals toward the margin. With perhaps one or two very
limited exceptions, the lowest coal is not found workable near
the edge of the field. The most prominent exception to this
rule is the Breckinridge cannel coal, which will be referred to
in another place. The coal in the upper part of the general
section is not found until some miles within the coal fields,
and then it is not always workable; while the coals between
are nowhere workable within the present field under discus-
sion.
This fact has an important bearing upon the question of
the former connection of the eastern and western coal fields,
in that it indicates the original termination of the coal field by
a natural thinning out of the strata along a line probably to
the east of the present margin, which has retreated to its
present position under the influence of erosion.
It is the prevalent opinion among many western geolo-
gists, at the present time, that if the eastern and western
coal fields ever were connected at all, it must have been
around the southern end of the- Cincinnati anticlinal. At
present the least distance between the two fields is about
6o miles-from the outliers of the western coal field in Ed-
monson and Hart counties to those of the eastern field in
Clinton and Wayne counties. The character and position of
the strata in Edmonson county, at the extreme southeastern
corner of the western coal field, more closely resemble
the rocks of a similar horizon in the eastern field than at any
other point on the margin of the western field. In fact,
Wbile this is indeed the prevailing opinion among geologists, I have no longer any
doubt that it is entirely an error, and that the eastern and western coal measures were
once connected over a large part, if not the whole, of the Cincinnati axis. The evidence
will be given in the third volume of this series of reports and in the second volume of
Memoirs. N. S. S.
438

THE EASTERN BORDER OF THE WESTERN COAL FIELD. 17

going toward the Ohio river, the character of the section
changes rapidly, until it bears hardly the slightest resem-
blance to the rocks at the margin of the eastern field.
COAL.
It will be observed that there are four seams of coal in-
cluded in the general section; but one of these, at No. 7 of
the section, is so thin, and so rarely occurs, that it was a
question whether it was worth a place in the general section,
and it was only admitted after considerable hesitation. It will
not be numbered.
The coal at No. 4 of the general section has been seen at
few places, but it has been reported at a number of others, so
that finally it was considered best to give it a place in the sec-
tion. It is of no economic importance, as it has n