xt79zw18m308 https://nyx.uky.edu/dips/xt79zw18m308/data/mets.xml Jillson, Willard Rouse, 1890- 1918  books b92-141-29449554 English [s.n.], : Lexington, Ky. : Contact the Special Collections Research Center for information regarding rights and use of this collection. Geology Kentucky Floyd County. Outline of the geology of Floyd County, Kentucky  / by Willard Rouse Jillson. text Outline of the geology of Floyd County, Kentucky  / by Willard Rouse Jillson. 1918 2002 true xt79zw18m308 section xt79zw18m308 





























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AN OUTLINE



               OF THE


           GEOLOGY

                 OF


FLOYD COUNTY, KENTUCKY

                 BY



WILLARD ROUSE JILLSON
        B. S., M. S.
        Professor of
   Geology and Paleontology
         in the
    University of Kentucky



LEXINGTON. KENTUCKY
      1918

 This page in the original text is blank.


 




Sandy Valley was begun shortly after July 6, 1917, when the
writer, having removed from Tulsa, Oklahoma, where he had
been engaged for some time as a consultant in the geology of
oil and gas in the Mid-Continent field, arrived in Prestonsburg
to establish permanent residence. A general reconnaissance of
all of Floyd and parts of the adjoining counties, was first under-
taken, after which detailed studies of the stratigraphy and
structure of the main river valley and each of its principal
tributary water sheds Abbott, Middle, Beaver, Mud and a por-
tion of Johns creek were undertaken.
    The progress of this work in the field has been much facili-
tated by the use of the excellent topographical maps recently
prepared and issued for this district by t-he United States and
the Kentucky Geological Surveys at the scale of 1:62,500.
From these maps accurate elevations above sea level have been
available from numerous bench marks, and elsewhere approxi-
mate elevations have been determined by the interpretative
reading of surface-feature contouring. While the use of these
maps has advanced the work in this field, the lack of good roads
throughout Floyd County has greatly retarded and added to
the physical difficulties encountered in completing this study.
    All of the work in the field has been done horseback or
afoot as no modern buggy or automobile road exists in Floyd
County today. Investigations in the Big Sandy Valley proper
and up Beaver Creek and its Right Fork to Wayland have been
somewhat speeded by the use of the trains of the Chesapeake 
Ohio Railroad, but rail schedules at best, are poorly timed for
the advancement of work in the field, in the prosecution of
which, not infrequently under very trying conditions, the
writer has been very courteously treated throughout Floyd
County.

                        DRAINAGE

    All of Floyd County is drained by the Levisa Fork of the
Big Sandy. This master-stream heads somewhat to the south-
east of the Pine Mountain-the great barrier ridge between
Kentucky and Virginia. It flows in a meandering northwest-
wardly course from the Pike County line to Prestonsburg at
which point it turns to the north, a direction it maintains to and
beyond the Johnson County line. The "valley of the Big

 




Sandy"-as the west and main fork of the river is usually called
-is confined to the eastern-central part of the north half of the
county. Besides numerous smaller ones, three large tributaries,
Mud, Beaver and Middle creeks enter the river from the south
and west, while only one of comparable size-Johns creek-
joins it from the southeast.
    The width of the bottoms of the Big Sandy in this area
rarely exceed 1500 or 1600 feet and occasionally it is narrowed
down to not more than 750 or 800 feet, nearly half of which
is occupied by the stream channel alone. The width of the
inner valley-from ridge to ridge-is usually not more than a
mile and sometimes much less. The fall of the bed of the river
from Pikeville to Prestonsburg is forty-two feet and from Pres-
tonsburg to the vicinity of Paintsville it is twenty-three feet thus
giving an average slope of about 1.4 feet per mile.
    The bed of the stream is characterized by extensive de-
posits of loose sand interspersed with occasional outcroppings of
sandstone. These hard rock ledges provide, during the dry
period of the year, a flow pattern of successive shallow slack-
water pools and shoals which now effectually bar navigation,
though up to about 1910 small steamboats carrying both pas-
sengers and freight ascended this fork of Big Sandy during six
or eight months of the year a distance of about 100 miles above
the Ohio.
    A notable instance of the alteration of the pattern of drain-
age by piracy may be seen on the upperwaters of Right Middle
creek. This stream rises at Ivyton in Magoffin County and flows
to the southeast through the northwestern part of Floyd County
to join Left Middle creek about three miles nearly west of
Prestonsburg. From Prater branch, about two miles above Dot-
son P. 0., all up-stream branches of Right Middle creek includ-
ing the State Road Fork join the main creek valley at an acute
angle against the direction of stream flow. The original head-
waters of Right Middle creek is seen as about a mile above the
mouth of Richardson branch. All of the area drained by this
creek above this point-some 10 or 12 square miles mostly in
Floyd, but partly in MIagoffin County-has been diverted from
the drainage basin of the Burning Fork of Licking river by
Right Middle creek of the Big Sandy. This piracy has been
brought about by a gradual headwaters migration to the north-
                           -7-

 




west-still in process-caused by the shorter course and more
rapid down cutting of the very much lower waters of Right
Middle creek.

                      TOPOGRAPHY

    Although Floyd County is commonly referred to as one of
the "mountain" counties of eastern Kentucky, the description
is somewhat misleading for there are in fact, no real mountains
within its boundaries. The nearest and the only upland of
truly mountainous proportions in this part of the State is the
Pine Mountain which attains a crestal altitude of about 3000
feet near Jenkins, Kentucky. It lies some thirty-five miles in
an airline "up the valley" from Prestonsburg and is at least ten
miles removed to the southeast from the southern-most tip of
the countv.
    A great and intricately dissected tableland sloping to the
north and northwest, Floyd though not actually mountainous
is nevertheless, an extremely rough area topographically. In
its entirety the county is an internal part of the broad Cumber-
land plateau, a notoriously rugged upland which flanks the Al-
leghany mountains on the west from New York to Alabama.
Characterized throughout by meandering V-shaped valleys and
steep-sloped, sharp-crested ridges, Floyd County exhibits its
maximum elevation-2300 feet-on the drainage divide at the
head of Left Beaver creek two miles nearly due south of Weeks-
bury where it corners with Knott and Pike counties.
    The lowest elevation in Floyd Countv-600 feet-is found
at low water at East Point where the Big Sandy river flowing
to the north enters Johnson Countv. The maximum relief
exhibited in Floyd County is therefore 1700 feet. The im-
mediate relief in any given locality is usually not more than
600 or 800 feet, though 1000 to 1200 feet is commonly found
on the head-waters of Left Beaver creek. On the other hand,
below Prestonsburg to East Point the hilltops of the inner val-
ley rarely extend more than 400 or 500 feet above the bottoms
of the Big Sandy.
     The upper bottom or old flood plain of the river on which
the town of Prestonsburg is seated has an elevation of 641 feet
above sea level and from this by very gradual graduations the
bottoms of the main valley rise to 653 feet at Boldman on the
                           _-8-

 



Pike County line. The nice topographic adjustment of drain-
age levels in this district is further evidenced by the fact that
the bottoms of Johns creek at Thomas on the Pike County line
are 654 feet above tide while similar elevations are found in the
county road as far up the waters of Right Beaver creek as the
hamlet of Dinwood.
    As might be anticipated in an unglaciated upland area of
homogeneous sedimentary rocks where stream dissection has
reached maturity, there are in fact in Floyd County, Kentucky,
no broad upland flat lands, nor are there anywhere more ex-
tensive bottoms than those found in the great southwestern bend
of the river at Prestonsburg. Because of these topographical
pecularities, from the days of the earliest exploration and set-
tlement-1755 to 1790-down to this year of 1918, the activi-
ties of man in Floyd County have been largely confined to the
valley bottoms of the Big Sandy river and its principal tribu-
taries.
    While these originally rich and easily accessible lowlands
have been cleared and farmed for upwards of 150 years, the
upper slopes of the ridges, steep, thin of soil and cropped with
only the very greatest efforts-still stand, quite generally in
timber from which during the past quarter century the best
grades of hardwood-oak, ash, hickory, poplar and walnut have
been logged out to feed the great mills that stood during the
early part of this century in Ohio, West Virginia and Kentucky
near the mouth of the Big Sandy river.


                      LITERATURE

    The first printed reference to the geology and mineral
resources of Floyd County, Kentucky, is found in the Report
of Survey of Mountain Roads made by Napoleon Bonaparte
Buford to the House of Representatives of the Commonwealth
of Kentucky in 1836. In this brochure published as an ap-
pendix to the House Journal, the territory involving Floyd
County along the upper part of the road leading to Prestons-
b)urg and points farther up the Big Sandy river Mr. Buford
described as an "almost inaccessible portion of the State." With
more than passing interest he cites the "celebrated Burning
Spring on the road between Licking Station-IIow Salyersville
                           -9-

 



-and upper Middle creek" in Floyd County. This natural gas
spring, which the writer has visited and flamed on numerous
occasions, was again referred to as one "which constantly emits
a thick sulphurous vapor    and ignites on the application
of fire" by Judge Lewis Collins in his Historical Sketches of
Kentucky printed in Maysville in 1847.
    Twenty years after Mr. Buford's reconnaissance report to
the Legislature was put into circulation, Dr. David Dale Owen
in his Report of the Geological Survey in Kentucky for 1854
and 18.56, included a preliminary note of the Coal Measures at
Prestonsburg.  In this early report there also appeared an
analysis of Aaron and Bogg's coal taken from domestic mines
or "banks," as they were then called, located in the main Big
Sandy valley near the Johnson County line. This is the first
printed analysis of Floyd County coal. In 1861 there appeared
from the hands of Leo Lesquereux the first stratigraphic section
for Floyd County. It was printed with remarks concerning the
coals outcropping near Prestonsburg in his Report of the Fosgil
Flora and of the Stratigraphical Distribution of the Coal in the
Kentucky Coal Field.
    In 1877 Dr. Nathaniel Southgate Shaler, Director of the
Kentucky Geological Survey, issued his Preliminary [Geo-
logical] Map of Kentucky. It made use of seven distinct
colored patterns to exhibit the areal geology of the State, and is
the first map to indicate Floyd County as completely embraced
within the Coal Measures. A vear later-in 1878-there was
issued by the State Geological Survey the first of a series of
chemical reports, which continuing to 1913, presented analyses
of the coals, ores, mineral waters and soils of Floyd County
as executed by Dr. Robert Peter and his son, Dr. Alfred M.
Peter, chemists to the Survey in Lexington.
    Professor A. R. Crandall's Preliminary Report on the
Geology of Morgan, Johnson, Magoffin and Floyd Counties, a
24-page pamphlet, was issued by the Kentucky Geological
Survey in 1890, but unfortunately only a few citations touch on
Floyd County. Nevertheless it prepared the ground for Pro-
fessor Newton C. Brown's report on the Mineral Wealth of the
Big Sandy Valley From Louisa to the Head of Navigation
which was issued by the Government at Washington in 1900
as Document No. 326 of the United States House of Representa-
                          -10-

 




tives. In this very readable report, the most comprehensive
that had yet appeared, the design and the descriptions are those
of Professor Brown but the coals and the stratigraphy as applied
to that part of the valley embraced within Floyd County is the
labor of Professor Crandall.
    It may be stated without fear of contradiction that the most
extended work up to the present time discussing oil, gas and
coal in Floyd County has been done by Mr. Joseph B. Hoeing
and Professor Crandall. In 1905 the Kentucky Geological
Survey issued Mr. Hoeing's Oil and Gas Sands of Kentucky.
In it there appear numerous logs of wells drilled for oil and gas
in Floyd County and, as interpreted from these records, a de-
scription of the oil and gas producing formations in this part
of the upper Big Sandy Valley is given. During the same year,
Professor Charles J. Norwood, then the head of the State Geo-
logical Survey also issued Professor Crandall's Coals of the Big
Sandy Valley. This report describes in some detail the com-
mercial coals on Mud, Beaver, Middle creek and the Big Sandy
in Floyd County, and gives occasional measured sections, but
it is very weak in its regional correlation and general strati-
graphy.
    Five years ago-in 1913-the State Geological Survey of
which he was then the head, issued Mr. Hoeing's Coals of the
Upper Big Sandy Valley and the Headwaters of the North Fork
of the Kentucky River. Although this report represents a
great advance over anything that had preceeded it, no effort was
made apparently to present the entire stratigraphic section or
correlate other than a few of the lower coals of Floyd County
adjacent to the Big Sandy river, and its local tributaries, Ab-
bott, Middle, Beaver, Mud and Johns creeks. It should be
noted with credit to this report by Mr. Hoeing, however, that it
is the first and only piece of writing up to this time to attempt
an interpretation and description of the geological structure of
the surface rocks of Floyd County.
    In summation of all previous work in this area it is proper
to state that a careful review of the literature, while it reveals
some twenty-five or thirty separate maps and reports of specific,
if not detailed bearing, as indicated in the checklist of refer-
ences attached to these pages, no comprehensive report on the
geology and mineral resources of Floyd County, Kentucky, has
                           -11-

 




yet appeared. Such a report would be of very great value at
the present time due to the expanding interest in oil and gas
and coal development.

                      INDEX FOSSILS
    A careful search of the literature reveals nothing in print
on the paleontology or the paleo-botany of Floyd County, Ken-
tucky. This is not remarkable when it is considered that no
unit work on the geology of this part of the State has ever been
written. Nevertheless it is believed, in accord with casual dis-
coveries made in the northeastern part of the county during the
past mid-summer, that Floyd County affords an attractive op-
portunity for the invertebrate paleontologist.  Late in the
month of Aug-ust, 1918, while pursuing structural investiga-
tions, the writer came upon a remarkably prolific invertebrate
fossil horizon in a blue-gray limey shale on the Dr. G. T. Ken-
drick farm on the headwarters of Cow creek. This stream is a
westerly flowing tributary of the Big Sandy, debouching into
the river just east of Emma postoffice.
     The type fossil locality occurs about 400 feet up the branch
from the Kendrick dwelling which is seated just above Bear
Branch. Here a fossilferous shale, which may be styled "the
Kendrick," rises from the bed of the stream. It is a thin
sedimentary unit exhibiting a thickness of about eight or ten
feet in the lower part of the hills on either side. Stratigraphi-
cally this shale is about 150 feet above the Prestonsburg or Van
Lear coal and about thirty feet below a bench which is probably
the Whitesbiirg coal. Broad distribution of invertebrate shells is
found in the Kendrick shale, both in and outside of nodular
"cone-in-cone" masses. In a rather considerable collection of
fossils taken from the type locality on the Kendrick farm by
this writer there is at least one coral, fragmental parts of a
crinoid calyx, and a number of brachiopods, pelecypods, gastro-
pods and cephalopods.
     While specific determinations of this interesting group
of fossils have not been made, the coral is identified as Lopho-
phyllutm proliferum a definite index of the Pennsylvanian.
Among the brachiopods there are apparently about six different
species of Products, two Spirifers and several specimens of the
trim elongate Leda. Among the pelecypods there is the large
                            -12-

 



Deltopecten TexarnuR and among the gastropods a species of
Bellerophlon. The cephalopods are represented by at least one
very interesting Orthocera8, one or more Goniatitie8 and a
Nautilu8. On loose blocks of shale on the lower waters of Cow
creek the writer has seen the typical Lingula umbonata. Several
of these forms taken individually, and this group of fossils
considered as a unit are definitely characteristic of the lower
Pennsylvanian or Pottsville. The writer is of the opinion that
within a reasonable distance from this locality on the head of
Cow creek other interesting exposures of the Kendrick shale
may be found in Floyd County and that diligent search may
reveal additional limey-fossiliferous-shale beds both above and
below this horizon.
    In the field of paleo-botany, both the shales and the sand-
stones of widely separated localities give ample evidence of the
luxuriant plant life that was here existant during the growth
of the stratigraphic section. Brown sandstone casts of the roots
of Lepidodendron, Stigmaria, Calamite8 and Sigillaria are com-
monly found in both the beds of the streams and on the
hill-sides where they have been carried by stream action or
weathered out of the formations in situ, while the coals of the
area frequently reveal the carbonized figure of the bark, and
shales the outline of the leaves or branches of these old Coal
Measure tree-like plants.

                     STRATIGRAPHY
                       Exposed Rocks
    Unconsolidated beds of gravel, sand, clay and mud of
fluviatile origion ranging in thickness from five to about
fifty feet as a maximum are to be found bordering the Big
Sandy river and all of its tributaries throughout Floyd County.
These loose sediments make up the bottom lands of the river
and its tributary creeks and branches and are of Pleistocene
and Recent age. Soft and easily eroded, these stream deposits
are of much importance to agriculture, provide town and home-
stead sites and afford the easiest levels of communication, but
they contain no important mineral resources except an occas-
ional lenticular bed of sand suitable for building purposes.
    The hard rocks exposed at the surface in Floyd County are
all sedements, dominently sandstones, shales and coals of Potts-
                           -13-

 



vile (Lower Pennsylvanian) age. Igneous and metamorphic
rocks are unknown. Two calcareous horizons, the Kendrick
limey-shale at about 150 feet above the Van Lear or Prestons-
burg coal, and the Fossil limestone at about 400 feet above the
same coal bench are known, but as both are thin, rarely ex-
ceeding eight to ten feet, and occur in the stratigraphic section
well above ordinary farming and transportation levels, they are
usually covered with talus or timber and are inconspicuous in
the landscape. Nevertheless these calcareous horizons because
of their fossiliferous character are important markers in the
stratigraphy of the county though they appear to have been
entirelv overlooked bv both Professor Crandall in 1905, and
Mr. Hoeing in 1913 in their separate studies of the coals and
Coal 'Measture -ectionw of Floyd County.
    The entire stratigraphic section of Pennsylvanian rocks as
exposed in Floyd County slightly exceeds 1100 feet, the
maximum measurement for any single locality occuring on the
head of Left Beaver creek, some two miles above Weeksbury
at the Pike County line. Here a massive sandstone caps the
ridge underneath which occurs a coal of good thickness but
very small areal extent. It will here be called the Ridge coal.
The upper 350 or 400 feet of the section as found in the souther-
most tip of the couinty, and high in the hills, is dominantly
sandstone.
    In this area below the Ridge coal four rather thick coals
can be found spaced from 80 to 120 feet apart, if one is fortunate
enough to locate the few openings that identify them. What
the separate names of these upper coals may be, the writer is
unable to indicate specifically but since they occur well above
the Fossil Limestone, and the lowest of them about 400 feet
above the Van Lear or Prestonsburg coal, it is probable that
they are correlatives in ascending order of the Haddix, the
Hazard, the Flag, and the Hindman coals which have been
described by James M. Hodge in his Report on the Coals of the
Three Forks of the Kentucky River and its tributaries which
was published by the Kentucky Geological Survey in 1910.
    From the Hladdix coal which occurs about thirty or forty
feet above the Fossil limestone, down to the varying levels of
creek and river drainage, shales predominate in the succession
of exposed rocks of Floyd County. This lower 550 or 600 feet



-14-

 




of the stratigraphic section contains the two significant cal-
careous units-the Fossil limestone at about 450 to 500 feet
and the Kendrick shale at about 200 to 250 feet above the
lowest water level in the river.
7   Seven or eight coals occur in this lower part of the surface
section of the Pottsville rocks and it is to be noted that such
sandstone members as are a part of this division are found as-
sociated both above and below (1) the three Elkhorn coals (the
middle or No. 2 bench of which is the Van Lear or Prestonsburg
coal) and (2) the three higher associated coals which in de-
scending order are: the Fire Clay, Little Fire Clay and Whites-
burg seams. The somewhat higher Limestone coal, as it is
known elsewhere in Eastern Kentucky, occurs about thirty or
forty feet below the Fossil Limestone and is notably bedded
both top and bottom in heavy shale.
     The lowest exposed stratigraphic unit in Floyd County is
 the heavy gray-black, fine, carbonaceous shale found underlying
 a heavy massive, cross bedded sandstone at the juncture of
 Beaver creek and the Big Sandy river. At this locality this
 shale, a distinct Pottsville unit, can be seen just north of Allen
 Postoffice in the cliffs below the county road leading over Bull
 Mountain to Prestonsburg. It is also exposed opposite Dwale
 near the mouth of Cow creek and may be seen at various points
 up the Big Sandy river to the Pike County line.
     In summation the exposed 1100 or more feet of upper
 Pottsville rocks in Floyd County, exhibit principally sandstones
 in the upper half of the section and shales with two calcareous
 beds in the lower portion with an overall inclusion of twelve or
 thirteen separate coals eight or nine of which are locally, if not
 widely, of commercial importance. Of the workable coals the
 three lowest in the section which in descending order are the
 Elkhorn No. 3 (possibly the equivalent of the Amburgy in the
 valley of the North Fork of the Kentucky river as described
 by Mr. IHodge), the Elkhorn No. 2 (which is the Van Lear or
 Prestonsburg bench) and the Elkhorn No. 1 (noted as the Way-
 land seam) are the coals supporting the extensive and growing
 mining industry in the vicinity of Prestonsburg, up the Big
 Sandy river and oln Beaver creek and its branches. In order
 of superposition these upper Pottsville sediments may be tabu-
 lated as follows:



-15-

 




Ridge top at the head of Left Beaver creek.
1. Massive sandstone
2. Coal-"Ridge"
3. Interval, principally sandstone
4. Coal-"Hindman"
5. Interval, principally sandstone
6. Coal-"Flag"
7. Interval, sandstone
8. Coal-"Hazard"
9. Interval, sandstone
10. Coal-"Haddix"
11. Interval, shale
12. Fossil Limestone
13. Interval, shale
14. Coal-"Limestone"
15. Interval, shale and sandstone
16. Coal-"Fire Clay"
17. Interval, sandstone
18. Coal, thin-"Little Fire Clay"
19. Interval, sandstone
20. Coal-"Whitesburg"
21. Interval, sandstone and shale
22. Kendrick, limey shale
23. Interval, shale and sandstone
24. Coal-"Elkhorn No. 3"
25. Interval, shale and sandstone
26. Coal-"Van Lear, Elkhorn No. 2"
27. Interval, shale
28. Coal-"Wayland or Elkhorn No. 1"
29. Interval, sandstone
30. Lowest exposed bed, shale at Allen



450 to 500
.   feet














1 550-600
   feet



I



                    Unexposed Rocks

    The records of numerous wells drilled for oil and gas in
widely separated localities in Floyd County reveal an uninter-
rupted downward continuation of the surface sediments of up-
per Pottsville (Pennsylvania) age to a depth of about 850 or
900 feet below drainage. This upper portion of the subsurface
stratigraphic section is dominantly siliceous, though shales,
                          -16-



I
i
I

 




sandy shales and one, two or three coals are known to occur.
Somewhat removed to the southeast in the upper valley of the
Big Sandy river where this group of rocks is exposed in in-
creased thickness along the top and upperwestern slope of the
Pine Mountain, Ralph W. Stone in his report on the Coal Re-
esource8 of the Rus8ell Fork Basin in Kentucky and Virginia,
issued in 1908 has grouped them as a unit formation and styled
them the Lee sandstone. Farther to the north and elsewhere
generally the lower portions of this massive coal measure unit,
frequently, if not usually, exhibiting many white quartz pebbles
has been described as the Pottsville conglomerate.
    Separated by an erosional unconformity varying from a
few to perhaps as much as 100 or 150 feet from the heavy
bedded conglomeratic sandstones of the upper Pottsville
(Pennsylvanian) above, indurated sediments of Mississippian
age, limestones, sandstones and shales, exhibiting a thickness
of about 900 or 1000 feet continue the subsurface stratigraphic
section to a depth of about 2000 or 2100 feet. Due principally
to the thickening of the unexposed Coal Measure section, to the
southeast, the base of the Mississippian series will of course, be
found at greater depths in the southern part of the county
than at points farther north. The upper part of this subsurface
section of the Mississippian rocks has been described by Mr.
Stone as the Pennington shale. As a formation unit in Vir-
ginia it usually contains a considerable thicknesses of sand-
stone, but in Floyd County this sandstone known as the
"Maxon" by drillers is lenticular in character, varying in thick-
ness and may be entirely absent. In such instances only a few
feet of shale, sometimes reddish or pinkish gray is present as a
dependable correlative of the Pennington of the South and the
Mauch Chunk of the north.
    Beneath the argillaceous and siliceous beds of the upper-
most Mississippian, there is found in Floyd County about 200
or 250 feet of shelly and massive limestone, the upper third of
which is probably a time equivalent in deposition to the Chester
and the lower two-thirds to the St. Louis (Meramec) of the
Mississippi Valley. Below this prominent calcareous unit, the
Waverly vani-colored shales with two included, relatively thin
sandstones, the "Big Injun" and the Berea, extend downwardly
some 650 or 700 feet to complete the Mississippian section.
                           -17-

 




    At the base of the lowest Corboniferous beds, as described
above, a rather uniform, though not consistently black, but
usually dark, fine grained shale sets in and extends about 700
or 800 feet deeper. This is the correlative, in part at least,
of the Chattanooga and the Ohio shales, seen on outcrop at the
periphrey of the Bluegrass region of central northern Kentucky
and elsewhere in Ohio. A sedimentary unit of great promi-
nence in the sub-surface stratigraphic section of Floyd County,
like its correlatives to the northeast and north it is generally
regarded as of upper Devonian age.
    Beneath the Devonian black shale occurs a gray to brown
porus limestone that has generally been referred to, particularly
by oil and gas drillers, as the Corniferous, the exact identifica-
tion of which stratigraphically has not been made with assur-
ance. If it is the Corniferous-as is the first limestone beneath
the Chattanooga shale at the outcrop somewhat to the northwest
on the flank of the Cincinnati arch, as for example in Estill
County, Kentucky, it is probably of Hamilton or Onondaga
age and so would be middle Devonian, but such determinations
at the present time, due to the fact that only one or two wells
have so far penetrated this formation, must remain incon-
clusive.
     Beneath the lowest Devonian sediments, whatever they
may be, bard sedimentary rocks, dominantly calcareous, with
many shale intercalations and possibly a few thin sandstones.
referable to the Silurian, Ordovician and Cambrian systems are
thought to occur in a very considerable but unmeasured, because
undrilled, thickness in the lower subsurface stratigraphic section
of Floyd County.

                        STRUCTURE

     In its simplest conception the upper Pottsville or surface
sediments of Floyd County lie in a broad synclinal or down
fold between what Mr. Hoeing has called the "Paint Creek Up-
lift"-a high, faulted domal and anticlinal structure extending
generally in an east and west direction through central Johnson
and Martin counties on the north, and the Pine Mountain
Overthrust and Uplift which coincides with the Kentucky-Vir-
ginia line on the south. This broad syncline, exhibiting no
faults or sedimentary displacements of consequence, has its
                            -18-

 




lowest surface expression, as may be noted by the disappearance
of the Van Lear coal below river level, at a point about three
miles south of East Point. A major syncline, its axis extends
southwestwardly across lower Abbott creek, where it is not very
plain, and is again seen well defined near the forks of Middle
creek. From this locality it appears to follow a winding course
through the hills between Spurlock and left Middle creek to
the south and southwest into Magoffin County. From the low-
est point on the Big Sandy river, as indicated above, this
syncline is to be noted as plunging to the east onto the waters of
Johns creek past the hamlet of Edgar toward the Martin County
line where in the high timbered hills of this area its axis be-
comes less apparent.
         South of the trough of this broad syncline the surface
beds of the upper Pottsville formation steadily rise. The Van
Lear coal again comes to the surface at the mouth of Abbott
creek and continues on up to a point some forty or fifty feet
above the level of the flood plain of the river at Prestonsburg.
In this rapid upfold, evidenced at many points by the Van
Lear or Prestonsburg coal, one limb of the prominent Prestons-
burg anticline located on the lower waters of Middle creek and
the Big Sandy river is seen. Proceeding further up the river
the pronounced eastern extension of this large anticlinal or
doming structure, the apex of which is found on the mid-waters
of the Bull creek, is seen about one mile by the river below the
mouth of Cow creek.
    Another well defined extension of the Bull creek anticline
or upfolding may be seen at the mouth of Beaver creek where
the Van Lear coal is some seventy-five or eighty feet above the
river plain. Farther up the river valley proper, at the mouth
of Ivy creek another doming, the Ivy anticline of northeast-
southwest strike crosses the Big Sandy followed on the southeast
by a paralleling syncline. From this point up the river the
Coal Measures continue their steady rise as indicated by the Van
Lear coal which is about 750 feet above sea level at the Pike
County line.
    Elsewhere in Floyd County the character of local surface
structure is not as apparent as in the main river valley, which
with its numerous cliffs and coal mines affords ready access
to the lower coals and their changing elevati