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GEOLOGICAL SURVEY OF ALABAMA QUADRANGLE SERIES MAP 37 PLATE 2 EXPLANATION FOR GEOLOGIC MAP AND CROSS SECTION SYMBOLS FOR GEOLOGIC MAP Contact, located very approximately Contact or fault, concealed beneath mapped units Alluvium. Unconsolidated silt, sand, and gravel containing clasts Frog Mountain Sandstone. Light-colored sandstone and dark-greenish-gray Qal of local bedrock. Mapped only along larger streams. Dfm and dark-brownish-gray silty and sandy mudstone; bluish-gray sandy chert at some locations; rare coarse bioclastic limestone locally at base. Thrust fault, located very approximately, sawteeth on upper plate QUATERNARY DEVONIAN 45 Strike and dip of beds Pottsville Formation upper part. Dark-gray silty shale containing Horizontal beds P pvu intervals of medium- to dark-gray lithic sandstone and interbeds of coal Little Oak Limestone. Dark-gray stylonodular limestone locally containing and underclay. Olo abundant fossil fragments. Vertical beds Pine Sandstone Member. Light-gray quartzose sandstone commonly Ppvp containing scattered quartz pebbles and quartz pebble conglomerate; lithic sandstone interbeds common in upper part. ORDOVICIAN Overturned beds 22 PENNSYLVANIAN POTTSVILLE FORMATION POTTSVILLE On Newala Limestone. Light- to medium-gray micritic limestone and dolomite. Strike and dip of foliation 30 Parkwood Formation and Floyd Shale undifferentiated. Dark-gray Anticline, showing trace and direction of plunge P AND Knox Group undifferentiated. Light- to dark-gray chert residuum commonly Mpwf OCk_ shale containing interbedded greenish-gray lithic sandstone and rare preserving textures of carbonate rocks; pinkish-gray bedded sandstone present locally. dark-gray argillaceous limestone. CAMBRIAN AND ORDOVICIAN Syncline, showing trace and direction of plunge KNOX GROUP KNOX MISSISSIPPIAN PENNSYLVANIAN Fort Payne Chert and Maury Formation undifferentiated. Thin-bedded, Mfpm SYMBOLS FOR CROSS SECTION A-A' medium-dark-gray limestone and dark-bluish-gray chert weathering to grayish- orange chert (Fort Payne). Pale-olive and grayish-red-purple mudstone locally containing discoid phosphatic concretions (Maury). Stratigraphic contact MISSISSIPPIAN Fault, showing relative movement, dashed where inferred Form lines CROSS SECTION A-A' A A' Helena thrust sheet Coosa synclinorium Eden fault Coosa deformed belt Pell City thrust sheet Ragland basin P pvp Alabama Highway Logan Martin 114 Lake (Feet) 700 700 (Feet) 500 500 P pvu (Sea level) 0 Pell City fault OCk_ 0 (Sea level) -500 -500 -1,000 P Mpwf -1,000 -1,500 -1,500 -2,000 P Mpwf P Mpwf -2,000 -2,500 -2,500 -3,000 P pvu P Mpwf -3,000 -3,500 -3,500 -4,000 Mfpm -4,000 -4,500 Pennsylvanian Hardwick Tunnel -4,500 member of Pottsville Formation* Olo -5,000 -5,000 Dfm On -5,500 Mississippian Pride Mountain Formation* -5,500 P Mfpm -6,000 pvp P Mpwf -6,000 -6,500 Pennsylvanian Shades Sandstone Member Dfm -6,500 of Pottsville Formation* -7,000 P Mpwf -7,000 P Mpwf Mfpm -7,500 Pennsylvanian Hardwick Tunnel Pennsylvanian Shades Sandstone Member -7,500 Mississippian Hartselle Sandstone* member of Pottsville Formation* of Pottsville Formation* -8,000 Dfm -8,000 -8,500 -8,500 P Mpwf Olo Olo Mfpm P Mpwf Mfpm -9,000 Olo -9,000 -9,500 Mississippian Hartselle Sandstone* Olo Dfm -9,500 Olo Mfpm -10,000 Mississippian Pride Mountain Formation* Mfpm -10,000 Dfm -10,500 Ordovician Greensport Formation, Little Oak Limestone, and Lenoir Limestone* -10,500 _ -11,000 P Mpwf OCk -11,000 -11,500 Helena fault -11,500 -12,000 -12,000 -12,500 Mfpm -12,500 Middle Ordovician -13,000 Silurian Red Mountain -13,000 Formation* Chickamauga Limestone* OCk_ -13,500 Cambrian Conasauga Formation* -13,500 Cambrian Cambrian Rome Formation* -14,000 Ketona Dolomite* -14,000 -14,500 Cambrian Conasauga Formation* -14,500 Cambrian -15,000 Conasauga Formation* Cambrian Rome Formation* -15,000 Cambrian Conasauga Formation* -15,500 Cambrian Conasauga Formation* -15,500 Cambrian -16,000 Cambrian Rome Formation* -16,000 Cambrian Rome Formation* -16,500 Rome Formation* -16,500 -17,000 -17,000 *Formations shown in cross section but not exposed on map (Plate 1) are included here to show structural relationships at depth. Scale 1:24,000 No vertical exaggeration CROSS SECTION A-A' AND EXPLANATION FOR THE GEOLOGIC MAP AND CROSS SECTION OF THE RAGLAND 7.5-MINUTE QUADRANGLE, ST. CLAIR, CALHOUN, AND TALLADEGA COUNTIES, ALABAMA By Denny N. Bearce Computer graphics by Don Wheat 2004 Berry H. (Nick) Tew, Jr. State Geologist.