State | Louisiana |
---|---|
Name | Prairie Terraces |
Geologic age | Pleistocene |
Lithologic constituents |
Major
Unconsolidated > Fine-detrital > Silt (Terrace-stream, Eolian-loess)
Unconsolidated > Fine-detrital > Clay (Terrace-stream)
Unconsolidated > Coarse-detrital > Sand (Terrace-stream)
Minor
Unconsolidated > Coarse-detrital > Gravel (Terrace-stream)
|
Comments | Surfaces generally show little dissection and are topographically higher than the Deweyville. Three levels are recognized:two along alluvial valleys, the lower coalescing with its broad coastwise expression;the third, still lower, found intermittently gulfward. Where overlain by loess, this unit has a red dotted overlay pattern on the source map. Polygons for this unit in our coverage which should have the loess overlay pattern are designated by "-l" being added to the base map unit symbol. |
References | Snead, J.I., and Mcculloh, R.P., 1984, Geologic Map of Louisiana: Louisiana Geological Survey, scale 1:500,000. |
NGMDB product | |
Counties | Acadia - Ascension - Avoyelles - East Baton Rouge - East Feliciana - Evangeline - Iberia - Lafayette - Livingston - Morehouse - Ouachita - Rapides - Saint Landry - Saint Martin - Saint Mary - Vermilion - West Feliciana |