GEOLOGICAL SURVEY OF ALABAMA QUADRANGLE SERIES MAP 58 PLATE
(ORME)
85o45' (SOUTH PITTSBURG)
615000m E 6 6 6 6 6 6 6 o o (SEQUATCHIE)
o TENN. 2 080 000 16 17 42'30'' 18 19 20 621 40' 22 23 624 ALA. 560,000 FEET 625 85 37'30''
35 00' ( o
Onvsr 12 35 00' CORRELATION OF MAP UNITS o
Qal o
( o
20o
o Qt Qal Quaternary ( 3 CENOZOIC Dc 4
8 5 (
220 000 unconformity
o TENN. (
FEET
16o
o !pv
(
o Pennsylvanian 38 000m o 73 N o o o ( o 18
16 6 6 14 38 Mp ( 73 ( Onvsr 8 4 17
Mbm Mtfpm Mississippian
Qal
Mbm ( Mtfpm
o ( Mtfpm (
Mp 5 ( O\k ( unconformity e Dc T. 1 S. Devonian
!pv Mbm
38 unconformity PALEOZOIC
72 T. 1 S.
o
Mbm o 3872 Srm Silurian ( 13o
4 ( unconformity
14 Mtfpm (
Osli
( Onvsr
D 1 630 000 ALA
( FEET Onvsr
o 7 ( Osli Ordovician
Mbm
( Dc unconformity
Qal ( 3871 o 11 O\k
( Mp Cambrian
( 3871
( Onvsr
D o
(
( DESCRIPTION OF MAP UNITS 3 o 4
Srm o
( af Mbm Artificial fill—Construction material.
12
(
o Qal
o Alluvium (Quaternary)—Unconsolidated sand, silt, clay, and gravel derived from local
o Mtfpm ( Onvsr
o 11
38 O\k 22 bedrock.
70 ( 15 o
18 4o
o D (
17 o 38 Qt Terrace deposits (Quaternary)—Reddish-orange sandy clay and gravel. Includes o ( 70 4 o
o
11 o ( subrounded to rounded oblate quartz and quartzite pebbles and cobbles and rare chert 8 12
17
( 19 pebbles.
A D (
(
o !pv
o Pottsville Formation (Lower Pennsylvanian)—Very light gray to pinkish-gray, fine- to
!pv (
Sequatchie fault O\k o 16 coarse-grained, thin- to massive-bedded, quartzose sandstone locally containing ( 18 4 o
11o ( Qal scattered to abundant, well-rounded quartz pebbles; quartz pebble conglomerate locally
7 o (
38 o
69 9 present (quartz pebbles up to 1 inch in diameter). Commonly crossbedded, locally (
12 o 57'30'' rippled and laminated. 57'30'' (
38
( 10 69
( Mp Pennington Formation (Upper Mississippian)—Contains a basal, light-gray to (
( e
5 ( Mtfpm ( Mtfpm ( medium-dark-gray, thin- to medium-bedded, finely crystalline, conchoidally fractured
o ( ( Mbm
Mbm (
( ( dolomite. Above the basal dolomite is light- to medium-gray, thin- to thick-bedded,
( ( Mtfpm ( ( o 4 skeletal wackestone/packstone that is locally argillaceous and contains nodules and beds
( D
Mbm ( Sequatchie anticline of black, dense, fossiliferous chert. Also in the lower part is pale-green to
( Onvsr pale-red-purple fissile shale. Upper part is dominantly light-brown,
( ( light-brownish-gray, pinkish- to olive-gray, thin- to medium-bedded, very fine to fine- 3868 Qal grained sublithic sandstone and light-gray, fissile shale.
( F 3868
( Qal Mbm Bangor and Monteagle Limestones undifferentiated (Upper Mississippian)—Bangor ( o Limestone: Predominantly medium-gray to dark-gray, thin- to thick-bedded, bioclastic
11 ( and oolitic limestone. Irregular nodules of black, dense chert are locally present
Qal Mbm o ( throughout. Upper part contains thin beds of light- to dark-gray dolomite. Beds of black 35
8 chert and medium-gray fissile shale are common. Monteagle Limestone: Lower part is ( o
Onvsr o
10 predominantly light- to medium-gray, thin- to medium-bedded, locally crossbedded
D D ( 3867 Onvsr o oolitic grainstone and skeletal packstone. Locally, some limestone beds contain small
10 ( Qal blebs, stringers, and thin beds of brownish-gray dense chert. Upper part is light- to
O\k Qal 3867 Qal medium-gray, thin- to massive-bedded, locally crossbedded oolitic/peloidal skeletal
o grainstone. Some interbeds of olive-green to greenish-gray shale are present.
18 Mtfpm o Tuscumbia Limestone, Fort Payne Chert, and Maury Formation undifferentiated (DORAN COVE)
Mtfpm (Lower and Upper Mississippian)—Tuscumbia Limestone: Light- to dark-gray, thin-
o 13
o D to massive-bedded, skeletal packstone/grainstone containing light-brownish-gray to (NEW HOME) 16
16
o Mtfpm dark-yellowish-brown nodules and beds of mealy, cavernous, and locally dense
3866 o fossiliferous chert. Locally, an interval of chert-free oolitic and skeletal limestone about 11
o 3866 40 feet thick is present. Fort Payne Chert: Medium-gray to white to grayish-orange, 10 10
o
o irregularly bedded, locally fossiliferous chert. Maury Formation: Light-pale-olive to
o Mtfpm
23 o medium-dark-green, blocky mudstone containing phosphate nodules in the upper part.
10
11 Dc 8 o o Mtfpm Chattanooga Shale (Upper Devonian)—Black to dark-gray, laminated, fissile, 17 13 carbonaceous shale containing interbeds of light-brown, fine-grained sandstone. A
Onvsr 6-inch-thick, limonite-cemented, poorly sorted sandstone marks the base.
3865 o 15 !pv Srm Red Mountain Formation (Lower and Upper Silurian)—Lower part is olive-green to Mtfpm D
Osli !pv 38 medium-gray blocky mudstone and fissile shale containing thin-bedded, coarsely
D 65 o Dc o crystalline limestone. The upper part is mostly olive-gray to olive-green shale with thin
5 D
7
Onvsr interbeds of light-brown to grayish-orange, fine-grained sandstone/siltstone and thin-
o Qt 25 bedded light-brown to light-bluish-gray crystalline limestone. Rare grayish-orange
o chert beds up to 3 inches thick are locally present. Srm 55' o 55' 7
13 Mtfpm Osli Sequatchie Formation, Leipers Limestone, and Inman Formation undifferentiated
Qt (Upper Ordovician)—Sequatchie Formation: Pale-yellowish-brown to o
38 o 64 Sand Mountain syncline
17 pale-red-purple, coarse-grained, thin- to massive-bedded, crystalline, iron-cemented,
14 o o Mtfpm 38
o 64 bioclastic limestone and limey sandstone containing scattered coarse sand grains and
8 Mp Qal o 10 Onvsr 11 o interbedded dusky-yellow fissile shale. Leipers Limestone: Lower part is medium- to 8
2 medium-dark-gray, flaggy- to lenticular-bedded, locally laminated, silty lime mudstone
D and skeletal wackestone with interbedded dark-greenish-gray, calcareous shale. The o Qal
o 15 o
27o
9 upper part is dark-olive-green to medium-dark-gray, thin-bedded, calcareous shale and
o 17 D
11 light-olive-gray to greenish-gray lime mudstone and skeletal wackestone. Inman
o Formation: Lower part is greenish-gray, pale-yellowish-orange and o
o D !pv
38 63 27 15 grayish-yellow-green calcareous shale, argillaceous limestone, and skeletal wackestone.
af o 12 o o 38 Locally, a light-brown to grayish-orange-pink dolomitic limestone marks the base. 22 12 63
T. 1 S.
10 Mtfpm Upper part is very light gray, dusky-yellow-green, medium-grayish-blue, thin- to T. 2 S. o medium-bedded lime mudstone and silty limestone containing maroon and yellow clay
4 T. 1 S. mudstone/shale interbeds.
T. 2 S. Onvsr
1 600 000 Nashville and Stones River Groups undifferentiated (Middle Ordovician)—Nashville o
ALA. o
FEET Oslio
o Group: Medium-dark-gray, thin- to medium-bedded, argillaceous limestone with
15 7
o
o 13 6 o !pv interbedded lime mudstone, fossiliferous limestone, and medium-gray shale interbeds.
3862 9 14 4 Stones River Group: Light- to light-bluish-gray to dark-gray, thin-bedded, fenestral
Qal o
af 3862 mudstone and skeletal wackestone that locally is argillaceous. Upper part is o 5 D
6 Qal light-bluish-gray to greenish-gray and medium- to dark-gray, thin- to massive-bedded, o
D fossiliferous limestone containing thin beds and nodules of bluish-gray, D
3 medium-dark-gray to dark-gray dense chert. Light-greenish-gray, laminated bentonitic shale is near the upper contact.
O\k o Mtfpm Knox Group undifferentiated (Upper Cambrian and Lower Ordovician)—Light-gray
Mbm to greenish-gray, thin- to thick-bedded, finely to coarsely crystalline, siliceous dolomite 3861 4
180,000 TENN. D FEET that is locally laminated. At the surface, the Knox weathers to cherty residuum where
o 3861
D chert generally preserves the sedimentary features of the original carbonate rocks.
D Mp 3 o
Qal D 3 A' e Mp SYMBOLS FOR GEOLOGIC MAP Mp !pv D Contact, dashed where located very approximately, showing location of control point
D !pv
D (contact exposed or closely located) !pv
D Contact, concealed beneath mapped units 3860 !pv 38 000m ( ( Qal 60 N Thrust fault, located very approximately, sawteeth on upper plate 34o52'30'' D 34o52'30'' o 6 6 ( ( ( 85 45' 615 R. 8 E. R. 9 E. ALA. 530 000 FEET 16 17 618 42'30'' 619 620 621 40' 622 623 624 TENN. 2 110 000 FEET 625000m E 85o37'30'' Thrust fault, concealed beneath mapped units R. 9 E. R. 10 E. (TRENTON) (FLAT ROCK) Trace of anticline axis, located approximately Base topographic map U.S. Geological Survey 1947 F (STEVENSON) (Photorevised 1983) MN GN ILL. Digital database by G. Daniel Irvin Water boundary KENTUCKY SCALE 1:24,000 MO VA 15 Produced in cooperation with the U.S. Geological 0o41’ o Strike and dip of bedding o 1 1/ 2 0 1 MILE 3 26’ 12 MILS TENNESSEE N.C. Survey, National Cooperative Geologic Mapping Program, 61 MILS e Location of horizontal bedding Cooperative Agreement G09AC00200 1 1/ 2 0 1 KILOMETER MISS S.C. ALA GA
Polyconic projection. 1927 North American datum UTM Grid and 2010 Magnetic North CONTOUR INTERVAL 20 FEET QUADRANGLE LOCATION 10,000-foot grid based on Alabama (East) Declination at Center of Sheet NATIONAL GEODETIC VERTICAL DATUM OF 1929 rectangular coordinate system SYMBOLS FOR CROSS SECTION A-A' Map rotated 0.8 degrees clockwise for display Stratigraphic contact Fault, showing relative movement, dashed where inferred
Sequatchie Sequatchie Sand Mountain syncline A fault anticline A'
Rocky Springs William Jones Irondale Branch Bridgeport Hogjaw Ridge Tennessee River Barton Point Sand Mountain Road Reservation Lively Creek !pv
Mp Mtfpm Mbm 500 (Feet) Onvsr 500 (Feet) Mtfpm Mbm Srm Mtfpm Dc Srm 0 (Sea level) (Sea level) 0 O\k Osli -500 Osli Dc -500 Onvsr Onvsr -1,000 -1,000 O\k -1,500 Conasauga Formation -1,500 O\k -2,000 -2,000
GEOLOGIC MAP OF THE BRIDGEPORT 7.5-MINUTE QUADRANGLE, JACKSON COUNTY, ALABAMA, AND MARION COUNTY, TENNESSEE by G. Daniel Irvin and Philip A. Dinterman 2012 Berry H. (Nick) Tew, Jr. State Geologist