DESCRIPTION OF MAPPED UNITS—Adapted from Martin (2004) and Martin and others (2007). EXPLANATION GEOLOGIC SETTING SUBCROP GEOLOGIC MAP (CRETACEOUS/TERTIARY) JACKSON FORMATION—Sand, silt, clay, and clay. Sand, fine- to coarse-grained, poorly to well-sorted, angular to well- The Jackson Purchase Region of western Kentucky is located in the northeastern part of the Mississippi Embayment. Rocks JACKSON PURCHASE REGION, WESTERN KY Tj rounded quartz; silty, clayey, cherty, micaceous, contains heavy minerals; also contains granules and pebbles of quartz and sediments exposed in this region range in age from Devonian to Holocene. The Mississippi Embayment, an area known as and subangular to subrounded pebbles and cobbles of clay; very thin- to thick-bedded and sometimes poorly bedded or Contact Unconformity contact the Jackson Purchase in Kentucky, is a broad, south-plunging syncline whose axis coincides with the Mississippi River. Deeper USGS STATEMAP Deliverable massive, commonly crossbedded; unconsolidated, but locally cemented with iron oxide. Silt, fine- to medium-grained, Paleozoic rocks dip northward toward the Illinois Basin, whereas most Upper Cretaceous and Tertiary formations strike parallel Series XII, 2009 consists of angular to subrounded quartz grains, clayey, sandy, micaceous, and carbonaceous; laminated to thin-bedded Approximate contact Unconformity concealed to the margin of the embayment and dip uniformly toward the embayment axis. This map displays the the subcrop geology of the Version 1.0 to massive, and commonly interbedded with sand or clay. Clay, silty and sandy, slightly lignitic, composed dominantly area below the mapped Quaternary/Tertiary section along the top of the Cretaceous/Tertiary unconformity. of kaolinite, with some illite, montmorillonite, and mixed-layer clay; thin- to thick-bedded, thinly laminated in places; Inferred contact Bedrock topographic contour (Jackson Purchase) contains leaf imprints, and locally contains fragments of lignitized wood; occurs as very thin to thick beds and lenses. Structure contour (Mississippi Plateau) Distribution of Jackson age sediments is irregular and thickness is variable. The distribution pattern suggests an irregular Concealed contact PRODEDURE erosional surface between rocks of Claiborne and Jackson age. Index contour (200 foot) Fault This map was generated from edited portions of the original compilation of fifty-five 1:24,000-scale Digitally Vectorized CLAIBORNE FORMATION—Sand, silt, and clay. Sand, silty and clayey, fine-to medium-grained, commonly very coarse Geologic Quadrangle (DVGQ) maps from the Murray, Paducah, Sikeston, and Cape Girardeau 30 x 60 minute quadrangles. The Tc and granular near contact with underlying unit, well to poorly-sorted, angular to subrounded quartz, chert, opaque Inferred fault State boundary original dataset was compiled and published by Steven L. Martin (2000a,b, 2004) and Martin and others (2007). In addition to

Y minerals, and rare small fragments of rod-like kaolinite crystals; crossbedded at places; local indurated zones cemented the Jackson Region, the new map includes a portion of the Mississippi Plateau east of the Tennessee River along the eastern map

R by iron oxide or secondary silica near lower contact; disseminated angular to well-rounded clay pebbles and cobbles at County lines border. The map illustrates faults, bedrock topography, and structure contours from the original geologic maps along with newly A

I A IS Concealed fault D N L

T some horizons, and lenses of clay breccia and clay gravel in sand near base of unit. Silt, variably sandy and clayey, mapped (inferred) formation areas. The compilation dataset was edited for this contract deliverable by mapping the exposed and E A T A P O D P P

R S N O O laminated, thin-to massive-bedded; commonly interbedded with sand and clay; locally micaceous. Clay, variably sandy concealed bedrock contacts, approximating their subsurface extent where covered by Quaternary sediments and not mapped, and M A J R E L O B T

T E and silty, kaolinitic, carbonaceous, and rarely lignitic; thin to thick-bedded; occurs in laminae, thin beds, and beds and excluding all mapped Quaternary and Quaternary/Tertiary surface units (i.e., Qal–alluvium, Ql–loess, QTc/QTg–continental M lenses several feet thick, commonly interbedded with silt and sand. Marked erosional unconformity at base. deposits and gravel). Additional subsurface contact information was inferred from available U.S. Geological Survey map data

R H (Olive, 1980). O W E H A H R O T C A E T I L N T T L S R D WILCOX FORMATION—Sand, clay, and silt. Sand, silty and clayey, very fine- to very coarse-grained, well- to poorly- A R E A U C S E N S C E D S U T T E A A C E S IT V Y R Tw B H A D L R L T R E A P W A A P A I G V sorted, angular to well-rounded quartz, chert, and sparse heavy minerals; also contains angular to well-rounded grains, 89º L P E Y C I 37º 15' C R pebbles, and boulders of silty clay derived from nearby slightly older clay bodies; thin- to thick-bedded, locally C E crossbedded, and cemented by iron oxide or secondary silica to form indurated layers; commonly argillaceous, locally L E L T F E I F L V A G M T I IL I micaceous and carbonaceous. A distinctive lithology in this unit is a “sawdust sand”, which occurs as discontinuous A L E R N R A Y K V C E A U H 37º 15' D A B O B W IC L S V G T lenses and is composed of quartz, clay, and chert grains, and sparse to moderately abundant kaolinite crystals. Clay, N L L S N W A E E M E N I IN L V M Y IE M O B O S R silty and sandy, massive to thin-bedded; carbonaceous, rarely lignitic, pyritic, and micaceous; occurs as lenses L R I P B B interbedded with sand and silt. Silt, clayey and sandy, commonly thinly laminated and thin to thick-bedded, and KENTUCKY E N F T F S O N intergrades with clay; micaceous, and carbonaceous. I E T S L Mu L G R Y Y N G K W U C R I E IN A V IN IC H L B N M O L IN N T IL A R K E L W U R F P L D A O A M A C T R E T O F I S K S H A A D N PORTERS CREEK CLAY—Clay and sand. Clay, sandy and silty, micaceous, glauconitic in lower part of unit, sparse iron- E H R E O I F Tp W A sulfide nodules and grains, and carbonized and pyritized wood; consists of quartz and clay minerals (calcium F montmorillonite, illite, kaolinite, clinoptilolite, and gypsum). Sand, clayey, very fine- to medium-grained, quartz, sparse QUADRANGLE LOCATIONS F N N N L D D O O O O IN L T dark minerals, and rare fragments of lignitized plant material; micaceous, glauconitic in lower part of unit, argillaceous; N T T L Y R W A K N IE G E E G L I B N O A L U F I S T C N IS Y K X I I K S occurs as thin beds in lower part and is dominant in upper part. Clastic dikes occur locally. O C D M H A IR E H E M R D S E U A K U

Y F R R C O

R TKcm ID E R T A T D CLAYTON AND McNAIRY FORMATIONS—The Clayton and McNairy Formations are combined for mapping purposes I D S D N D C A A R A N L N T TKcm M E A R A E E R E A because of the general concealment of the contact and because of lithologic similarities of the formations. The Clayton H B E U M C I L A F E Y A R T B K K Y L L ) T W D T C A H E B I N E Y D E U U A N I A L U V N E A W R IN E L C C Z E Formation is poorly to moderately consolidated, poorly exposed, and consists of sand, clay and silt. The disconformity N O H O H T W L C N Y V R E L S A L O A O T B U V N H R N C M R Y R R L U N A at the base of the Clayton Formation is widespread in the Mississippian Embayment. The McNairy Formation is poorly to C G M O H C moderately consolidated and poorly exposed, and consists of sand, clay, and gravel. An erosional unconformity occurs ( C at the base of the McNairy Formation. Clastic dikes occur locally.

CLAYTON FORMATION— Sand, clay, and silt, interbedded. Sand, variably clayey and silty, very fine-to medium-grained, well sorted, quartz and dark heavy minerals; micaceous, glauconitic, and carbonaceous; locally, tightly cemented by ferruginous material. Clay, silty and sandy, contains blebs of fine angular micaceous quartz sand; lignitic, and glauconitic; thinly laminated to thin-bedded and occurs as lenses. Silt, clayey, well-sorted, very fine-grained, quartz and dark heavy minerals; micaceous and locally carbonaceous.

McNAIRY FORMATION—Sand, clay, and gravel. Sand, silty and clayey, fine to medium-grained, well-sorted, quartz and Km

S sparse dark heavy minerals; contains irregular patches of chert pebbles and granules near base, and clay blebs and

U streaks; locally micaceous; thin- to thick-bedded, and locally well-cemented with iron oxide. Clay, variably silty, Tp O

E micaceous; occurs as laminae, seams, thin layers, lenses, and irregular masses. Gravel, well-rounded to subrounded C

A chert pebbles in quartz sand matrix; occurs in thin, scattered lenses near base of section. T E

R TUSCALOOSA FORMATION—Gravel, sand, silt, and clay. Gravel, subangular to well-rounded, poorly sorted, pebbles, 88º 30' Mme Mkc Pca

C R Kt E cobbles, and rare boulders of chert; chert sand, silt, and clay present as interstitial matrix; chert commonly tripolitic; IV bedding rare or crudely crossbedding, and locally cemented with iron oxide or silica; local thin lenses of chert sand and R O H clayey silt. Sand, silty and clayey, very fine- to very coarse-grained, dominantly chert. Silt, commonly indurated, clayey, 400 I N and sandy. Clay, slightly sandy, siliceous. Formation rests unconformably on rocks of Mississippian and Devonian age. O A Mch I R N IO I LIVINGSTON A Tw V CASEYVILLE FORMATION—Siltstone, sandstone, and shale; interbedded and in part lenticular. Siltstone, thin-bedded, H Tp V E TKcm 0 L O R Pca micaceous, locally argillaceous; locally contains thin interbeds of silty shale. Sandstone, quartzose, micaceous, fine- to 0 Y Km 4 S coarse-grained, thin- to thick-bedded, locally crossbedded, graded bedded and ripple-marked; subrounded to rounded N Mpt

N Paducah chert and quartz granules and pebbles locally abundant and generally concentrated in lower parts of beds. Beds locally McCRACKEN 0 E 0 0 4

P contain clay pellets, interstitial clay, and coal near the base; ferruginous concretions locally abundant; plant casts and 20 5 Mgd molds locally present. Shale, variably silty or sandy; locally carbonaceous and contains small siderite nodules. Mfp

MISSISSIPPIAN ROCKS, UNDIFFERENTIATED—Unit equivalent to unnamed or unknown Mississippian rocks below main BALLARD 40 Mu channel of Tennessee River (Kentucky Lake area) or Ohio River. 0 Mw Kt Tw 400 0 CHESTERIAN SERIES UNITS, UNDIFFERENTIATED— Unit equivalent to unnamed or unknown Upper Mississippian 20 Mch rocks (Chesterian Series) below main channel of Ohio River, mapped locally in Little Cypress quadrangle. R Mss iver KINKAID LIMESTONE, DEGONIA SANDSTONE, CLORE LIMESTONE—Combined unit mapped in isolated fault segments Mh Mkc Km ssee in Little Cypress quadrangle (See descriptions below). Tenne

KINKAID LIMESTONE—Limestone, shale, sandstone, and siltstone, interbedded. Limestone, thin- to thick-bedded, Tw Mh Mfp Mw 0 micrograined limestone and coarse- to medium-crystalline calcarenite, locally argillaceous or sandy, fossiliferous, 0 0 2 dolomitic, and contains local chert nodules and shale partings. Shale, variably silty and sandy, calcareous, fossiliferous, 20 Mu 0 0 and contains siderite concretions. Sandstone, fine-grained, well-sorted, locally calcareous and argillaceous; contains 0 1 abundant shale partings and clay pebbles; irregular bedding planes and locally crossbedded. Siltstone, thin- to medium- 37º 00 bedded; argillaceous and locally very fine-grained sandstone. 6

DEGONIA SANDSTONE—Siltstone, shale, sandstone, and chert, interbedded. Siltstone, micaceous and locally 0 0 400 Km 0 calcareous, thin- to medium-bedded, locally grades into fine-grained sandstone, and overlies thick-bedded chert; 1 dolomitic and siliceous. Shale, variably silty and sandy, and slightly calcareous near base of unit. Sandstone, fine- grained, medium- to thick-bedded, and argillaceous. Chert, medium- to thick-bedded; bedding planes undulate and are ripple marked. 37º Mfp 600 CLORE LIMESTONE—Limestone, shale, sandstone, and siltstone, interbedded. Limestone, dense to finely crystalline, Wickliffe TKcm thin- to medium-bedded, some beds dolomitic, many beds argillaceous, scattered chert nodules, some beds very 5 4

fossiliferous. Thin beds of sandy and silty shale and dolomitic limestone in upper part of unit. Shale, silty, commonly Tp 0 0 calcareous, fossiliferous, locally pyritic; interbeds of limestone common. Sandstone, fine-grained, medium-bedded, Mw slightly calcareous and micaceous; crossbedding common. Siltstone, shaly, thin-bedded; calcareous cement.

PALESTINE SANDSTONE—Sandstone, shale and siltstone. Sandstone, variably silty and shaly, fine-grained, medium- to R Mpt thick-bedded, few thin beds, thinly crossbedded, ripple marks common, scattered clay pellets; micaeous, slightly E Tw V calcareous. Shale, variable silty and sandy; scattered siltstone lenses and beds common, and scattered lenses of fine- I Dcc grained sandstone; slightly calcareous, carbonaceous. Siltstone, variably shaley and sandy, thin-bedded, beds R Kt LYON commonly lenticular, bedding planes commonly irregular. Mapped locally in Little Cypress quadrangle.

I

P Tj MENARD LIMESTONE—Limestone and shale, interbedded. Limestone, variably silty or sandy, dense to finely crystalline, P 200 Tc Mme thin- to thick-bedded; few dolomitic beds, locally siliceous, argillaceous, fossiliferous; chert nodules and beds. Shale, I S

variably silty, fissile, commonly calcareous, fossilifersous; contains interbedded dolomite and limestone. Mapped locally S in Little Cypress quadrangle. I S T S Kt I e WALTERSBURG SANDSTONE AND VIENNA SANDSTONE—Mapped locally in Little Cypress quadrangle. (See 400 n M Mwv n descriptions below). e

s

s WALTERSBURG SANDSTONE—Sandstone, shale, and siltstone, interbedded. Sandstone, fine-grained, thin- to thick- 0 e 0 e bedded, some beds separated by thin shale laminae; crossbedded. Shale, variably sandy and silty, fissile, calcareous, 4 fossiliferous, contains siderite nodules. Siltstone, thin- to medium bedded, even bedded; argillaceous; contains abundant Tc interstitial chlorite, noncalcareous. 5 400 VIENNA SANDSTONE—Limestone, shale, and chert; interbedded. Limestone, dense to finely crystalline, shaly, locally Bardwell R siliceous and dolomitic, fossiliferous, scattered chert nodules, lenses, and beds. Shale, fissile, fossiliferous, calcareous; MARSHALL iv Km e occurs as interbeds and laminae. Chert, as lenses and beds interlayered with limestone. r 88º TAR SPRINGS SANDSTONE—Sandstone, shale, and siltstone, interbedded. Sandstone, generally quartzose, locally Mts argillaceous, fine-grained, thin- to thick-bedded, ripple-marked and crossbedded; some lenticular beds; many shaly Tc Mss N partings; locally carbonaceous; contains a few flattened clay pebbles; fossiliferous. Shale, fissile, silty, slightly A

I 200 5

P calcareous, carbonaceous, fossiliferous; contains laminae and thin beds of sandstone and siltstone, and locally includes

0

P Benton 0 I nodules and layers of siderite. Siltstone, thin-bedded, micaceous, slightly carbonaceous; some lenticular beds. Mapped GRAVES Mw

4

S 800

S locally in Little Cypress quadrangle. I 0 Mnp

S 0 4 Mfp S I GLEN DEAN LIMESTONE—Limestone, shale, and sandstone. Limestone, fine- to coarse-grained, medium- to thick- 1200

M Mgd Tj 400 bedded, rarely thin-bedded; thicker beds commonly separated by thin shaly partings, and a few thin beds of sandstone; TKcm 4 CARLISLE 0 fossiliferous, argillaceous, locally siliceous, slightly dolomitic. Shale, commonly calcareous; present as thin interbeds 0 and laminae. Sandstone, fine- grained, slightly calcareous; some disseminated pyrite. Mapped locally in Little Cypress quadrangle. 400 HARDINSBURG SANDSTONE—Sandstone, shale, siltstone, and coal, interbedded. Sandstone, quartzose, silty, variably Mh micaceous, locally calcareous, fine-grained, thin- to thick-bedded; ripple marks and crossbedding common; few clay pellets; shaly partings and laminae; some interstitial dolomite cement. Shale, silty and sandy, locally carbonaceous; Mfp shaly coal underlain by underclay; abundant plant impressions; thin laminae of shale common in sandstone and siltstone. Siltstone, thin-bedded, even-bedded, micaceous, argillaceous, rarely carbonaceous. Coal bed near base of unit, 400 underclay with scattered carbonaceous material is overlain by shaly coal with abundant leaf impressions. Mapped in isolated fault segments in Little Cypress quadrangle. Mw STE. GENEVIEVE LIMESTONE—Limestone, sandstone, shale, and siltstone, interbedded. Limestone, variably sandy and 400 Tp Msg slightly argillaceous, finely to coarsely crystalline; some beds are dolomitic; some beds shaly, medium- to thick-bedded; Kt crossbedded, fossiliferous, oolitic, cherty. Sandstone, fine-grained, thin- to thick-bedded, calcareous cement; commonly Km crossbedded, locally ripple-marked; commonly interbedded or associated with silty calcareous shale. Shale, variably 0 0 TRIGG sandy and silty, calcareous; occurs as thin interbeds. Siltstone, medium-bedded, calcareous, discontinuous. Mapped 2 locally in Calvert City quadrangle 4 0 0 4 0 ST. LOUIS AND SALEM LIMESTONES—Limestone and chert. Limestone, argillaceous, partly silty; fine- to coarse-grained, Tc 0 Mss medium- to thick-bedded; interbedded thin shaly beds; dolomitic; petroliferous odor; oolitic, cherty, fossiliferous. Chert Mayfield 5 occurs as sparse to common spheroids, discoids, irregular knobby bodies, and discontinuous layers; some shows wavy laminations. 0 40 0

WARSAW LIMESTONE—Limestone and chert, interbedded. Limestone, fine- to coarse-grained, medium- to thick-bedded, Tj 0 4 Mw fossiliferous, rarely oolitic; argillaceous; some beds separated by thin shale laminae; chert nodules common; crossbedded. Chert occurs as nodules, irregular beds, and discontinuous layers in finer-grained limestone. Kt

FORT PAYNE FORMATION—Limestone and chert; interlayered. Limestone, variably silty and clayey, micrograined to 0 Mfp 0 fine-grained, siliceous, argillaceous, locally shaly, fossiliferous. Chert present in beds and lenticular masses. 2 HICKMAN NEW PROVIDENCE SHALE—Shale, thinly laminated; contains greenish-gray siltstone lenses; glauconitic clay at base. Mnp Mapped in isolated fault segments in Birmingham Point, Briensburg, and Fenton quadrangles. 400

N CHATTANOOGA SHALE—Shale, carbonaceous, fissile, pyritic; contains thin beds of micaceous silt. Mapped in isolated

A Dc I fault segments in Briensburg and Calvert City quadrangles. N 5 TKcm O Clinton 4 Tw V CHERT AND CLAY DEPOSITS—Chert, fossiliferous, granular texture, thin-bedded, interbedded with layers of silty clay; 00 E Dcc

D probably residum from limestone. Mapped in isolated fault segment in Birmingham Point quadrangle.

0 0 4

0 0 2 CALLOWAY 4 00

Mu 200 R IV Tj E R Murray 5 Mw T e

n

Tc n

e

s 5 s Hickman e

e

I P P I 200 FULTON S S FULTON I S S Mfp I R Tj i M v

e

r

4 0 Km 0 400 36º30'

89º 30'

Mw 89º TKcm 4 0

0 0 40 88º 30' Kentucky Single Zone: North American Datum of 1983 (NAD83) REFERENCES 36º 30' Lambert Conformal Conic map projection with double standard parallels at 88º 38 deg 40 min Latitude North and 37 deg 05 min Latitude North Martin, S.L., 2004, Geologic map of the Murray and part of the Sikeston 30 x 60 minute quadrangles, western Kentucky: Kentucky Geological SUBCROP GEOLOGIC MAP OF CRETACEOUS/TERTIARY SECTION, Survey, ser. 12, Geologic Map 8, scale 1:100,000.

Martin, S.L., 2000a, Digital geologic map of the Jackson Purchase Region, western Kentucky , in Soller, D.R., ed., Digital Mapping Techniques JACKSON PURCHASE REGION, WESTERN KENTUCKY '00—Workshop Proceedings: U.S. Geological Survey Open-File Report 00-325, p. 177. Compiled by Thomas N. Sparks DISCLAIMER ACKNOWLEDGMENTS Martin, S.L., 2000b, Geologic map of the Jackson Purchase Region, western Kentucky , in Smath, R.A., and Davidson, B., eds., Economic and Although these data have been processed successfully on a computer system at the Kentucky Geological Survey (KGS), This map was generated using previously published data from 1:24,000-scale Digitally Vectorized Geologic Quadrangle engineering geology of the Jackson Purchase Area, Kentucky: Year 2000 Annual Field Conference of the Kentucky Society of Professional Modified from compilations by Steven L. Martin, Warren H. Anderson, and Thomas N. Sparks no warranty, expressed or implied, is made by KGS regarding the utility of the data on any other system, nor shall the act of (DVGQ) maps of the Murray, Paducah, Sikeston, and Cape Girardeau 30 x 60 minute quadrangles completed by KGS personnel Geologists, plate 1, scale 1:200,000. distribution constitute any such warranty. (1999–2004) and compiled by Steven L. Martin (2000a,b, 2004) and Martin and others (2007). This work was funded in part by 2009 KGS does not guarantee this map or digital data to be free of errors or inaccuracies. Some cultural features originate from the U.S. Geological Survey National Cooperative Mapping Program under the STATEMAP Program authorized by the National Martin, S.L., Anderson, W.H., and Sparks, T.N., 2007, Geologic map of part of the Paducah and Cape Girardeau 30 x 60 minute quadrangles, t data sources other than KGS, and may not align with geologic features on this map. KGS disclaims any responsibility or liability Geologic Mapping Act of 1992, Grant No. 08HQPA0003, and by the Kentucky Geological Survey. SCALE 1:125 000 western Kentucky: Kentucky Geological Survey, ser. 12, Geologic Map 14, scale 1:100,000. for interpretations from this map or digital data, or decisions based thereon. Digital mapping for the bedrock topographic and structure contours was initially completed by Steven L. Martin from the 2 0 2 4 6 8 10 The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily original geologic maps. Olive, W.W., 1980, Geologic maps of the Jackson Purchase Region, Kentucky, U.S. Geological Survey Miscellaneous Investigation Series Miles representing the official policies, either expressed or implied, of the U.S. Government. Subsurface information was used from data on file at the Kentucky Geological Survey as well as map data contributed by Map I-1217, scale 1:250,000. the U.S. Geological Survey (Olive, 1980). 2 0 2 4 6 8 10 12 14 16 Kilometers