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Mineral Resources > Online Spatial Data > Geology > by state > Arkansas Geology

Geologic units in Saline county, Arkansas

Alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 6 % of this area

Alluvium - Alluvial deposits of present streams

Lithology: alluvium

Midway Group (Phanerozoic | Cenozoic | Tertiary | Paleocene) at surface, covers 3 % of this area

Midway Group

Lithology: clay or mud; mixed clastic/carbonate; sandstone; limestone

Arkansas Novaculite (Phanerozoic | Paleozoic | Devonian-Late Carboniferous Mississippian-Early) at surface, covers 1 % of this area

Arkansas Novaculite - Includes upper division (Mississippian), middle division (Mississippian and Devonian), and lower division (Devonian)

Lithology: novaculite; shale

Claibourne Group (Phanerozoic | Cenozoic | Tertiary | Eocene-Middle) at surface, covers 5 % of this area

Claibourne Group

Lithology: sand; clay or mud; coal

Stanley Shale (Phanerozoic | Paleozoic | Carboniferous Mississippian-Early) at surface, covers 7 % of this area

Stanley Shale - Includes Chickasaw Creek Chert equivalent of Harlton (1938) near top and Hatton Tuff Lentil and Hot Springs Sandstone Member near base

Lithology: shale; sandstone; siltstone; chert; tuff

Terrace deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Late) at surface, covers 4 % of this area

Terrace deposits - Alluvial deposits on one or more terrace levels

Lithology: alluvial terrace

Missouri Mountain Shale and Baylock Sandstone (Phanerozoic | Paleozoic | Silurian) at surface, covers 1 % of this area

Missouri Mountain Shale and Baylock Sandstone - The Baylock Sandstone is present only in the Cross, Cossatot, and Trap Mountains. Missouri Mountain Shale is mapped with Polk Creek Shale and Bigfork Chert in the area between Paron, Saline County, and Little Rock

Lithology: sandstone; shale; conglomerate; siltstone

Wilcox Group (Phanerozoic | Cenozoic | Tertiary | Eocene-Early) at surface, covers 17 % of this area

Wilcox Group

Lithology: sand; silt; clay or mud; gravel; coal

Jackfork Sandstone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early [Morrowan]) at surface, covers 12 % of this area

Jackfork Sandstone

Lithology: sandstone; shale

Pole Creek Shale (Upper Ordovician) and Bigfork Chert (Upper and Middle Ordovician) (Phanerozoic | Paleozoic | Ordovician-Middle Ordovician-Late) at surface, covers 5 % of this area

Polk Creek Shale (Upper Ordovician) and Bigfork Chert (Upper and Middle Ordovician)

Lithology: chert; shale; limestone

Womble Shale (Middle Ordovician) (Phanerozoic | Paleozoic | Ordovician-Middle) at surface, covers 31 % of this area

Womble Shale (Middle Ordovician)

Lithology: shale; limestone; sandstone

Igneous rocks (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 0.5 % of this area

Includes undifferentiated altered sedimentary rocks of Paleozoic age at Granite Mountain, Pulaski County, and Mufreesboro, Pike County. Acid to intermediate - Nepheline syenite complexes at Magnet Cove and Potash Sulfur Springs, stocks at Granite Mtn., explosion breccias, and dikes and sills (principally trachyte,tinguaite, phonolite, some ranging from syenite to diabase.) Basic to ultrabasic - Lamproite pipes (Murfreesboro, Pike County) and dikes and sills (principally lamprophyres of fourchite, ouachitite, and monchiquite)

Lithology: alkalic intrusive rock; nepheline syenite; syenite; intrusive carbonatite; trachyte; lamprophyre

Olistoliths of Metagabbro and Soapstone-Serpentine (Phanerozoic | Paleozoic) at surface, covers < 0.1 % of this area

Olistoliths of Metagabbro and Soapstone-Serpentine - Altered peridotite

Lithology: gabbro; serpentinite

Blakely Sandstone (Middle and Lower Ordovician) (Phanerozoic | Paleozoic | Ordovician-Early Ordovician-Middle) at surface, covers 4 % of this area

Blakely Sandstone (Middle and Lower Ordovician)

Lithology: shale; sandstone; conglomerate

Mazarn Shale (Phanerozoic | Paleozoic | Ordovician-Early) at surface, covers 3 % of this area

Mazarn Shale

Lithology: shale; sandstone; limestone