Alluvial deposits.

Deposits in valleys consisting of gravel, sand, and silt. Includes younger terrace deposits. May contain some glacial deposits and colluvium in uplands. (Quaternary Sediments).
State Idaho
Name Alluvial deposits.
Geologic age Quaternary
Lithologic constituents
Major
Unconsolidated > Fine-detrital > Silt (Alluvial, Terrace-stream, Colluvial, Glacial)
Unconsolidated > Coarse-detrital > Gravel (Alluvial, Terrace-stream, Colluvial, Glacial)
Unconsolidated > Coarse-detrital > Sand (Alluvial, Terrace-stream, Colluvial, Glacial)
References

Lewis, Reed S., Link, Paul K., Stanford, Loudon R., and Long, Sean P., Geologic Map of Idaho, 2012, Idaho Geological Survey, Geologic Map 9 (M-9); Scale 1:500,000.

NGMDB product
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