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Alluvial, coastal and low terrace deposits

Alluvial, coastal and low terrace deposits - Varicolored fine to coarse quartz sand containing clay lenses and gravel in places. Gravel composed of quartz and chert pebbles and assorted metmorphic and igneous rock fragments in streams near the Piedmont. In areas of the Valley and Ridge province gravel composed of angular to subrounded chert, quartz, and quartzite pebbles. Coastal deposits include fine to medium quartz sand with shell fragments and accessory heavy minerals along Gulf beaches and fine to medium quartz sand, silt, clay, peat, mud and ooze in the Mississippi Sound, Little Lagoon, bays, lakes, streams, and estuaries.
State Alabama
Name Alluvial, coastal and low terrace deposits
Geologic age Holocene
Primary rock type beach sand
Secondary rock type alluvium
Other rock types
Lithologic constituents
Major
Unconsolidated > Coarse-detrital > Sand (Terrace, marine)
Minor
Unconsolidated > Fine-detrital > Clay (Alluvial)
Unconsolidated > Coarse-detrital > Gravel (Alluvial)Gravel composed of quartz and chert pebbles and assorted metmorphic and igneous rock fragments in streams near the Piedmont. In areas of the Valley and Ridge province gravel composed of angular to subrounded chert, quartz, and quartzite pebbles.
Incidental
Sedimentary > Chemical > Chert
Unconsolidated > Peat (Terrace, marine)
Unconsolidated > Fine-detrital > Silt (Alluvial)
Unconsolidated > Marl (Terrace, marine)
Map references
Szabo, M. W., Osborne, E. W., Copeland, C. W. Jr., Neathery; T. L., 1988, Geologic Map of Alabama, Geological Survey of Alabama Special Map 220, scale 1:250,000.
Unit references
Szabo, M. W., Osborne, E. W., Copeland, C. W. Jr., Neathery; T. L., 1988, Geologic Map of Alabama, Geological Survey of Alabama Special Map 220, scale 1:250,000.
Counties Autauga - Baldwin - Barbour - Bullock - Butler - Cherokee - Chilton - Choctaw - Clarke - Conecuh - Coosa - Covington - Dallas - Elmore - Escambia - Etowah - Fayette - Franklin - Geneva - Greene - Hale - Henry - Houston - Lamar - Lee - Lowndes - Macon - Marengo - Marion - Mobile - Monroe - Perry - Pickens - Russell - Saint Clair - Sumter - Washington - Wilcox