xt7jq23qvv26 https://exploreuk.uky.edu/dips/xt7jq23qvv26/data/mets.xml Norwood, Charles Joseph, b. 1853. 1880  books b96-13-34924086 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 Ohio County. General account of the geology of a part of Ohio County  / by Charles J. Norwood. text General account of the geology of a part of Ohio County  / by Charles J. Norwood. 1880 2002 true xt7jq23qvv26 section xt7jq23qvv26 













GEOLOGICAL SURVEY OF KENTUCKY.
          N. S. SHALER, DIRECTOR.



        A GENERAL ACCOUNT

                  OF THE

GEOLOGY OF A PART OF OHIO COUNTY,



BY CHARLES J. NORWOOD.

PART V. VOL. V. SECOND SERIES.



STURWTY-PD FOR -F R SURVY-  Y MAJOR, JOHNSON & RARR-, YEOMAN PR, .IEAEIORY, RY.
                                   77 & 78

 










PRELIMINARY LETTER.



Professor N. S. SHALER, Director Kentucky Geological Survey:
  DEAR SIR: I herewith present the results (that are ready
for publication) of my work in Ohio county. It is proper to
state, that a number of matters have been left undiscussed,
although notes were taken concerning them, as it seemed best
that they should be considered in a report dealing with the
county considered as a county alone. In this report the coun-
ty is especially considered with respect to its value in aiding
to make clear the history of the western coal field.
  The acknowledgments of the Survey are due the citizens
of the county generally for their cooperation in furthering the
work in their respective regions, but especially are they due
Mr. Harrison D. Taylor, Judge Baird, Dr. J. E. Pendleton,
Hon. E. Dudley Walker, Mr. J. E'. Barrett, and Mr. Carson,
of Hartford; Mr. R. B. Thomson, of Elm Lick, and Mr. S.
Woodward. Dr. Pendleton, Mr. Carson, and Mr. Woodward
presented specimens of archa0ological value to the Survey;
Mr. Taylor and Judge Baird furnished maps, and Mr. Thom-
son rendered very material assistance to me in a number of
ways.
                            Respectfully,
                                    C. J. NORWOOD.
78

 










A GENERAL ACCOUNT OF THE GEOLOGY OF A
              PART OF OHIO COUNTY.


                           PREFACE.
  The conditions of the beds in Ohio county depend essen-
tially on two nearly parallel disturbances, one of which is an
uplift, apparently a synclinal, and traverses the county in an
irregular eastwardly and westwardly direction; the other, a
disturbance lying within the counties to the south of the Ohio
line, near the southern border of the coal field, and which
seems to have been, in a large degree, instrumental in shap-
ing the form of the southern limit of the field.
The counties nearest to Ohio county, within which this south-
wardly disturbance lies, are Butler and Muhlenburg. Accord-
ingly, the southern part of Ohio county, and the northern parts
of Butler and Muhlenburg counties, are found to lie within a
common geological basin, which is a synclinal one.
  North of the Ohio county disturbance the beds seem to have
one general sweep-a downward one-towards the north,
nearly, if not quite, to the Ohio river. The amount of the
depression of the beds, however, varies in that direction; ap-
parently being inconsiderable in the direction of Hawesville,
Hancock county, but sufficient in the direction of Owensboro',
Daviess county, to bring the upper coals within the hills facing
the river, near that city.
  We find, therefore, in Ohio county two distinct geological
areas: one occupying the southern half of the county, and
forming, with parts of Butler and Muhlenburg counties, a
I It is possible that the very low rocks seen at Hawesyille (beds at the base of the coal
measures are visible there) may have been brought to light by another disturbance-
causing a northwardly rise of the beds. Of this, however, I have no accurate knowledge,
and refer to the forthcoming report of Mr. P. N. Moore, on the geology of that region,
for the solution of this question.
                                                             79

 


A GENERAL ACCOUNT OF THE



synclinal basin, which reaches from Rough creek to the south-
ern margin of the coal field; the other, an area with a single
slope, and that towards the north. There certainly are local
modifications of these conditions; but such seems to be a
correct view of the general arrangement of the geological
features of the regions.
  The two regions seem to differ in some special particulars
besides the relative positions, towards the surface, of the beds
beneath it.
  There -seem to be indications of a wedging out (so to call
it) of some of the beds towards the north, and a lessening in
the thickness of some of the coal seams; hence it is not im-
probable that a larger number of coals are to be found south
of the Ohio county disturbance than north of it. This is con-
jectural, however; and even should it prove true, it does not
seem to have been effected by the disturbance-so far as the
early history of the coal beds is concerned. This will become
apparent further on.
  It will be seen that each area has a certain individuality,
which serves as a distinguishing feature, and that it is of suffi-
cient importance to render the study of each section, by it-
self, desirable. Accordingly, the plan has been to limit the
study of the geology of these districts less by the geograph-
ical than by the geological lines; so that the study of either
section should not be confined to a single county, but would
include such parts of the other counties as came within the
geological bounds. With this in view, and in order that the
report may be used in connection with, and properly form a
part of, the record of the general results obtained in the study
of the synclinal basin, only the southern part of Ohio county
-somewhat more than half of the county-is now described.

                              1.
                        TOPOGRAPHY.
  The topographical features of the district differ little from
the general type presented in the interior portions. of the
western coal field. Soft sandstones and beds of shale of vari-



4

 


GEOLOGY OF A PART OF OHIO COUNTY.



ous sorts (usually sandy shale) are the elements from which
have resulted a region of much flat land, a few prominent
ridges, and occasional conical or flat-topped hills.
  The accidents to which the crust has been subjected, viz:
the disturbance along Rough creek, with its attendant twist-
ing of the beds, and the uplift at the southern margin of the
field, have impressed themselves on the geography of the
region in a general way; but the chief features of the topog-
raphy, so far as relates to details, have been determined by
the simple erosion or wearing down of sandstones (usually
incoherent) and sandy or clay shales, according to localities.
The valley of Muddy creek, of Lewis creek in part, and prob-
ably of Rough creek, have been largely determined by dy-
niamical agencies; but the character, both as to course and
size, of the larger number of the drainage channels, has de-
pended entirely on the character of the underlying beds and
the various degrees of resistance with which they have with-
stood atmospheric effects.  It is not uncommon to find in-
stances where the course of a valley has been altered by the
lateral passage of shale into sandstone, or vice versa. The
effect, on the topography, of the few limestones which occur
in the section, seems to have been very limited. In the region
about Sulphur Springs, and eastwardly and westwardly from
there, along Rough creek, the Sub-carboniferous limestones
have given an area of occasional underground drainage, and
produced somewhat of the peculiar topography we find when
it is based on such beds; but the limestones are so intimately
associated with sandstone and sandy shale, that the general
features are still very largely those of what may be termed
"sandstone topography." The area of the Sub-carboniferous
limestones is also quite limited, being confined to a compar-
atively narrow strip along Rough creek.
  The principal streams of the district, besides Rough creek,
are Caney creek, Hall's creek, Mill run, Muddy creek, and
Walton's creek-all of which are tributaries of Rough creek
-Lewis creek, Bull's run, Slate creek, and Indian Camp creek
(the head waters)-all of which flow into the Green river.
    voL v.-6                                              82



5

 


6A GENERAL ACCOUNT OF THE



Chief among these streams are, (X) Caney creek, which flows
into the county from Grayson county, and then flows north-
wardly, approximately parallel with the eastern boundary of
the county; (2) Muddy creek, which flows in an irregular
westwardly course, and empties into Rough creek about one
mile and a half below Hartford, draining the region princi-
pally about Elm Lick and Rosine; (3) Lewis creek, which
flows westwardly into the Green river, and drains the larger
part of the southern portion of the district; and (4) Walton's
creek, which drains the larger part of the region about Cen-
tretown, and flows northwardly into Rough creek.
  The principal ridges of the district are three in number, and
are, (a) one bordering on Muddy creek, south of the stream,
(b) one lying farther to the south, whose southern slope is
drained by Lewis creek, and (c) the "Jerusalem" ridge in the
region of Rosine and Elm Lick, which is drained in part by
Muddy creek. The general course of these ridges is north
of westwardly. There are other ridges, especially north and
northeastwardly from Elm Lick and Rosine, which are promi-
nent features in the topography of the region. but their extent
is usually short, and their courses quite irregular. The first
ridge (a), which may be termed the "Muddy Creek ridge," is
a low one, for the larger part of its course, and is compara-
tively short; it seems to coincide with the second ridge (6)
towards the west, or to fall away and disappear in that direc-
tion; it has not been determined which condition occurs. To-
wards the east it breaks up in a series of rounded hills, which
are washed by the numerous small tributaries of NMuddy creek.
  The second ridge (6) may be termed the "Coal ridge," as
within it are contained the largest number of important coal
beds to be found in any one ridge in the district. This ridge
is apparently a part of the main ridge of the coal field, which
has been mentioned in a preceding report. and will be more
fully discussed hereafter.
  The Jerusalem ridge (r) is also an important ridge; but,
although it contains a thick and important coal bed, does not
  See part VII, volume IV, Kentucky Geological Reports, N. S. Shaler, Director.
S2



6

 


GEOLOGY OF A PART OF OHIO COUNTY.



have equal value, so far as concerns coal, with the "Coal
ridge."
                              II.
    THE GENERAL STRUCTURE AND COURSE OF THE UPLIFT.
  Naturally, one of the most interesting features in the struct-
ure of the district is the disturbance which forms its northward
limit; hence the discussion of it will serve as a fitting intro-
duction to the general account of the other features of the
region. It is a line of uplift which stretches across the county
in a somewhat irregular eastwardly and westwardly direction,
extending to the Falls of Rough, and perhaps beyond, on the
east; and through McLean county as far west as Sebree, in
Webster county, and probably beyond.
  The existence of the disturbance was discovered by Dr. D.
D. Owen; but he does not seem to have recognized its full
importance, or to have traced it for any distance, nor to have
determined its nature.  He mentions it as the "Barnett's
creek disturbance," probably referring to the region about the
old salt wells, on Barnett's creek, and does not seem to have
traced it any farther towards the east.
  The disturbance was for the first time suspected by myself
in March, i874, upon a visit to a point on Rough creek, above
Hartford, known as the -Iron Mountain."  The discovery of
Sub-carboniferous beds there, and the inclination of the strata,
proved the existence of some sort of disturbance, but of what
kind was not known. Another visit made to the locality in
1875, and the examinations, undertaken along the north and
south running railways in the same year, proved the disturb-
ance to have a considerable extent; but it was not until May,
1876, that its true significance and general character became
apparent, and it was determined to be a line of uplift. The
uplift is probably connected with the disturbance in Union
county, described by Dr. Owen, and designated as the " Bald
Hill disturbance. "  This, however, is entirely conjectural, as
  See page 147, volume I, Kentucky Geological Reports, old series, D. D. Owen,
Director.
tSee page 112, volume I, Kentucky Geological Reports, old series, D. D. Owen,
Director.
                                                           83



7

 



A GENERAL ACCOUNT OF THE



that disturbance has not been studied as yet by any officer of
the present Survey, nor the westward extension of this one
fully determined.
  The location of the uplift is distinctly marked in the geog-
raphy of the region by Rough creek, which, for the larger part
of its course, closely follows the line of the disturbance, never
permanently leaving it until within a few miles of the mouth
of the stream; it does not, in fact, pass entirely beyond the
limits of the uplift there. The detailed relations that exist
between Rough creek and the disturbance cannot well be de-
termined before the line of the uplift is accurately mapped;
but all the evidence collected, so far, seems to indicate the date
of the creek valley to be more recent than the disturbance,
and that the course of the creek has been considerably influ-
enced by the uplift. Although the disturbance is plainly an
uplifting of the beds, and along some parts of its course is
plainly an anticlinal fold, its general character, that which is
most common throughout its length, is yet somewhat con-
jectural.
  I am inclined to regard the uplift as an anticlinal fold, modi-
fied in its general character along some parts of its course.
The balance of evidence favors such a classification; but as
yet it must necessarily be a provisional one, as at some points
the disturbance exists as afazdt, while at some others the evi-
dence seems to point to a monodinal fold. So far as Ohio
county alone is concerned, the disturbance may safely be re-
garded as (most commonly) an anticlinal fold; but as it ex-
tends far beyond the limits of this COuL1ty, and must hereafter
be considered in the relation it bears towards other parts of
the coal field, it is desirable to avoid any name that may be
too local in its application. Accordingly, from the relations
existing between the disturbance and Rough creek, it is desig-
nated as the - Rough Creek uplift" in this and a preceding
report.
  The course of the uplift varies considerably. The strike of



 See R.po,, t , th, Ge-ogy of the R-gi-ns A,jarelt to /Ih A  Ath and S-th Running Rail-
wnys, part VII, volume IV, new series, Kentucky Geological Reports, N. S. Shaler,
Director.
84



8

 


GEOLOGY OF A PART OF OHIO COUNTY.



the beds ranges from north 400 east, in the vicinity of Hart-
ford, to north 850 east (though more commonly north 70o east),
in the region about Sulphur Springs and Barrett's Ferry,
while west of Hartford the variation is from north 30 west
to north 850 west-the strike of the beds at the old salt
wells, on Barnett's creek, however, being north 550 west to
north 650 west. We thus find an almost complete swinging
around of the line of the uplift westwardly from Hartford.
  There seems to be little room to doubt, that when the line
of the uplift is accurately mapped, it will be found to be marked
very faithfully by the course of Rough creek; for that stream
seems to depend very largely on the turns of the line of the
uplift for its more important changes of direction. The value
that the uplift has in directing the course of the stream is
curiously illustrated by the decided curve to the south made
by the stream when north of Hartford, and the turn then
made towards the north just after Hartford is passed. That
this is very largely due to the changes in the course of the
uplift becomes plain when a map (even a poor one) of the
line of uplift is compared with a good map of the stream-
which we fortunately have.
  From "Clifty Hill,' above Barrett's Ferry, to the Sulphur
Springs, and a short distance beyond, the general direction of
the uplift is about north 700 east; it then changes, and at half
a mile south of west of the Sulphur Springs bears north 65
east, and keeps this general course for several miles towards
the west. The course is then altered again, and bears north
400 east, at a point northwardly from Hartford.
  On the lower Hawesville road, northwestwardly from Hart-
ford, a good view of the tilted beds near the axis of the uplift
is obtained; their strike bears about north 85' west. This is
modified to north 300 west, still farther west, and is again
changed in the vicinity of the old salt wells on Barnett's creek,
the strike of the beds there being north 55' west to north 650
west.
  It will be seen that the course of the line of the uplift forms
somewhat of an open loop near Hartford-the open part of
                                                           8S



9

 


A GENERAL ACCOUNT OF THE



the loop being towards the north. The map of Rough creek
shows the same feature in the course of the stream. This
loop really represents a shallow synclinal in the vicinity of
Hartford, as will be seen from the following: In the immedi-
ate vicinity of Hartford, and for some distance north of the
town, the beds are found dipping nearly due west, the bearing
being a little north of a due west course; but west of the
town, on the west side of Rough creek, the dip is reversed,
and bears south of east-in some places nearly due southeast
-gradually, however, swinging around to the southwest to-
wards Barnett's creek.
  The existence of this synclinal may serve to explain the
southwardly course of the stream from the mouth of Flat Lick
to the mouth of Muddy creek, and its subsequent departure
from such close connection with the uplift as exists eastwardly
from Hartford. It cannot be said to ever pass entirely beyond
the influence of the uplift, for there is a marked relation be-
tween the strike of the uplifted beds and the course of the
creek, so far as it flows; but its channel is within a different set
of beds from those on its upper course (which are the older),
and the distance between the stream and the central line of
uplift is increased. This seems to be due to the southwardly
impetus gained by the stream when turned through the syn-
clinal valley.
  Northeastwardly from Hartford the beds, near the central
line of uplift, are frequently exposed within short distances of
Rough creek. On the Hartford and Sulphur Springs road,
Chester limestone, overlaid by about forty feet of shaly sand-
stone, is exposed in the divide between Hall's creek and Sul-
lenger's branch, about one mile from Hall's creek. Limestone
of the same age is exposed in the region about the Sulphur
Springs and Hines' Mill. In the vicinity of Sulphur Springs
the limestone is frequently found toward the base of the hills,
with massive sandstone above it.
For the details of the structure of this region, and of all that eastwardly to the Gray.
son county line, the reader is referred to the forthcoming report of Mr. P. N. Moore on
the Eastern Margin of the Coal Field.
86



to

 


GEOLOGY OF A PART OF OHIO COUNTY.



  Northeastwardly from Sulphur Springs a thin coal bed oc-
curs, in close connection with what seems to be Sub-carbonif-
erous limestone. The coal is about nine inches thick, and is
probably at the base of the coal measures. The precise age
of the limestone underlying the coal could not well be deter-
mined, but it seemed to belong to the Chester Group. The
coal is covered by four feet or more of drab sandy shale, and is
firm and glossy black. The beds seemed to be dipping at an
angle of about 60 course south 250 east. This is on Mr. N. P.
Boswell's land.
  At Mr. T. J. Barrett's " Sulphur Lick," about two and a
half miles north of east from the Sulphur Springs, a sandstone
is exposed which is tilted apparently at an angle of nearly 450.
Very little of the bed could be seen, so that the angle of the
clip may really not be so steep.  Limestone is reported to
have been found below the sandstone.
  In the Hartford and Hardinsburg road (the old "' Louisville
and Hopkinsville" road), about half a mile a little south of
east from the Sulphur Lick, sandstone, probably equivalent to
that seen at the lick, is exposed. The bed is dipping about
south 200 east, the strike being north 700 east. Chester lime-
stone is exposed in the road about seventy-five yards north-
wardly from the sandstone outcrop, but is apparently nearly
horizontal. Its place seems to be below the sandstone. Spi-
rifer increbescens is very abundant in the rock.
  About twenty yards beyond the limestone a thin seam of
coal, six to seven inches thick, is exposed, with a dip reversed
to that of the sandstone. There seems to be the axis of an
anticlinal here. This place is near Barrett's Ferry.
  At "- Clifty Hill," on the north bank of Rough creek, about
half a mile north 650 east above Barrett's Ferry, a fine view
of the central structure of the uplift is obtained. Tilted beds
of sandstone, shale, and Sub-carboniferous limestone are seen
in the following order:
  i. Massive limestone.
  2. Space; notably sandstone and shale, which are probably
crushed.
                                                          87



I I

 



A GENERAL ACCOUNT OF THE



  3. Massive compact sandstone.
  The beds are tilted at an angle of 60, so nearly as could
be determined; course about south 200 east. The arrange-
ment of the beds is shown in figure i, plate I.
  Chester limestone, overlaid by sandstone, is also seen in
the Hartford and Hardinsburg road, about one mile and three
quarters south of west from Barrett's Ferry. The beds at
this place seem to be nearly horizontal. Farther to the west,
at the crossing of Sulphur run, about one mile and three quar-
ters south 50 east from Sulphur Springs, the Chester beds
are again exposed-at the foot of the dividing ridge between
Sulphur run and Hall's creek. As the road mounts the ridge
rhomboidal blocks of sandstone are exposed, whose place is
above the limestone. The beds are nearly horizontal. The
lessening in the degree of the dip of the beds is plainly seen
as we recede from Rough creek.
  In the vicinity of Hartford lower members of the coal meas-
ures are exposed, which are affected by the dip of the Sub-
carboniferous beds to the north, but show a change in the
direction of dip, as compared with that seen towards Sulphur
Springs. At the Foreman Riffle," on Rough creek, about
half a mile above Hartford, shaly sandstone is exposed-the
beds dipping apparently south 450 west. 'rhe precise direc-
tion is obscure, as the outcrop is limited.
  At the -"water" mill, at Hartford, higher beds are seen,
consisting of sandstone, limestone, and coal, which have a
considerable dip nearly due west. At the mill the inclination
of the beds amounts to eight feet in one hundred and eighty
feet. On the Hartford and Hawesville road, about five miles
west of north from Hartford, Chester beds, consisting of sand-
stone, limestone, and shale, are exposed, inclined at a steep
angle. At one place the sandstone shows a dip of 28', course
south 600 west; this, however, seems to be a local exaggera-
tion, as the more trustworthy beds of limestone show a dip of
only i5', course south 250 west, which is probably the general
inclination of the beds in the locality.
38

 


GEOLOGY OF A PART OF OHIO COUNTY.



  On Barnett's creek, on Mr. Lewis Turner's land, and in Mr.
Stephen Woodward's field, near the "old salt wells," Sub-car-
boniferous limestones are exposed tilted at high angles. On
Mr. Turner's land the limestone, thirty feet of which is ex-
posed, is inclined at an angle of 400, course south 350 west.
This place is about three and a half miles, by map measure-
ment, above the mouth of Barnett's creek.
  Such are the features to be observed in a general survey of
the Rough creek uplift. The disturbance is certainly one of
the most interesting problems to be found in the western coal
field, not only in its scientific but economic bearings, and mer-
its a more extended study than it has yet received.

                             III.
         THE GENERAL STRUCTURE OF THE DISTRICT.
  As intimated on a preceding page, the principal topographi-
cal features of the district south of the Rough creek uplift are
a principal ridge, having a northwestwardly trend, which forms
the water-shed for the waters of Lewis creek on the south,
and the waters of Muddy creek in part, and of Rough creek
in part, on the north, and a subordinate ridge to the north and
south of the principal one; this is the "i Coal " ridge. These.
with the -,Jerusalem" ridge, are the principal features: but
they are not the only prominent ones. The "d Ben's Lick hills,"
between Brush creek and Ben's Lick creek (both of which
streams flow into Rough creek); a few conical hills on the
borders of Muddy creek; the ridge down which flow the
streams of Flat Lick, Mill Run, etc. (but which is very much
broken, and is really connected with the ridge northwardly
from Rosine). and the ridge at Point Pleasant and near Cen-
tretown, are also prominent. especially in their geological
value.
  The coal ridge, which, for the larger part of its course, lies
south of the railroad, and extends in an irregular line from
the head waters of Indian Camp creek to the Green river,
This is probably the locality visited by Dr Owen; see page 147, volume I, old series,
Kentucky geological Reports, D. D. Owen, Director.
                                                           89



13

 


A GENERAL ACCOUNT OF THE



with its various spurs, seems to contain not only a larger num-
ber of coals, but a larger area of thick beds than any of the
other ridges.
  The Ben's Lick hills contain some of the thick beds; the
Jerusalem ridge contains a bed from three feet ten inches to
six feet six inches thick (including a clay parting), and within
the ridge near Centretown, and at Point Pleasant, the thickest
bed of coal in the district is found; but compared with that of
the beds in the coal ridge, the area of the coals is small. The
precise value, in beds of coal, of the coal ridge, cannot be de-
termined until its form is accurately mapped.
  The general slope of the beds from the Rough creek uplift
is, east of Hartford, between 200 and 350 east of south; west
of Hartford the direction, as indicated on a preceding page, is
very variable, the general course, however, being southwest-
wardly. East of Hartford, the southwardly slope of the beds
seems to terminate at the valley of Muddy creek, giving place
thereat to a southwardly rise.
  The region west of Hartford has not been studied stiffi-
ciently in detail for the precise limits of the various dips of
the beds to be determined. The dip is not only very variable,
but complicated by a small fault, which extends northwardly
from Rockport, on the Green river. It may be said, however,
that, in that region, there is a general retreat, to the north-
ward, of the limit of the southward slope of the beds as the
Green river is approached; that is, the line limiting the south-
ward slope swings round west of Hartford and points towards
the northwest, in the direction of the Green river.
  It seems that, were these lines projected on a map, they
would be found to represent an imperfectly formed letter V
-one stem reaching out past Beaver Dam, Elm Lick, and
Rosine, and the other one extending towards Point Pleasant,
on the Green river-the angle being somewhere between
McHenry and the Lewis creek tunnel.
  South of these lines the strata rise towards the south. It
will therefore be seen, that the larger part of the valley of
Muddy creek is within a synclinal depression, the direction of



14

 


GEOLOGY OF A PART OF 01110 COUNTY.



which is northeastwardly. It seems, indeed, that the -Muddy
Creek" ridge, at the base of which Beaver Dam stands, may
be regarded as a synclinal one. It seems to be near the
central axis of the great synclinal (so to call it) extending
from the Rough Creek uplift to the southern border of the
coal field.

     NUMBER OF COAL BEDS AND THE GENERAL SECTION.
  There seem to be at least eleven distinct coals within the
district; but only ten have been fully identified. This does
not take into account the coals towards the extreme eastern
margin of the county, in which direction there is at least one
bed lower than the ones enumerated in the following section,
nor yet those lying closely along the uplift. So far, I have
been unable to satisfactorily obtain the direct connection be-
tween these lowest coals and the ones lying above them, on
account of the limited character of their outcrops, and the
difficulty of tracing the strata-a difficulty which will be recog-
nized by one who has worked in this coal field, where the beds
are seldom horizontal for any considerable number of miles,
and the structure is so frequently masked by disintegration of
the rocks. I have accordingly preferred to limit the section
more particularly to those localities where the element of dip
would have the least bearing in the computation of the dis-
tances between the beds; where, indeed, the direct connec-
tion of one bed with another one could frequently be ob-
tained, by simply descending from the one bed to the other,
without passing over any considerable horizontal distance.
In the region bordering immediately on the lower uplifted
rocks, the dip, as mentioned on a preceding page, is quite
variable, both in amount and direction. Farther to the south,
however, where the slope of the beds is towards the north,
the dip is more regular in amount, and more constant in direc-
tion; consequently, the relations between the beds are gener-
ally quite plain. In several instances, vertical sections of the
ridges have shown as many as four coals in orderly succession,
while many of the sections show from two to three coals fol-
                                                           9t



15

 


16              A GENERAL ACCOUNT OF THE

lowing one another within short horizontal distances. The
grouping of these sections, by the identification of some of
the members of one section with corresponding ones of an-
other, has resulted in establishing a general section showing a
thickness between five hundred and six hundred feet of beds
-including at least ten comparatively constant coals and one
whose character is yet conjectural.
  Even those coals that may be regarded as comparatively
constant are not, however, presumed to be present everywhere
that their horizons are reached. There seem to be at least
two whose places are sometimes filled with sandstone or beds
of shale; and the indications seem to be, that in the vicinity of
Fordsville (which, however, is north of the northern limit of
the synclinal basin) there is a shortening from the base up-
wards of the section, and an absence of some of the coal beds.
Whether this is actually the case, however, is as yet problem-
atical; and should it prove to be the case, the cause is as
yet imperfectly understood. There is this to be said, how-
ever, in such a connection: at Fordsville, and on the extreme
eastern margin of the district, the coal-bearing series rest
immediately on the Chester Sub-carboniferous) beds.  At
Fordsville, and near the Sulphur Springs, a thin seam of coal,
which may possibly be Coal L, rests within a few feet (some-
times within a few inches) of the Sub-carboniferous limestone.
This is to be observed at Spring Lick, in Grayson county, and
further east. At Spring Lick, Coal L occurs at five feet above
the Chester limestones
  Towards the southern border of the field, in Butler and
Muhlenburg counties, a conglomerated sandstone, known
simply as the "Conglomerate," lies at the base of the coal
measures, and is interposed between the lowest coal and the
Sub-carboniferous beds.  The same conditions as those to
which the Conglomerate owes its presence on the south, while
it is absent towards the east and on the northern limits of the
 For a full discussion of the section at Fordsville and surrounding region, see the
forthcoming report of Mr. P.