Alluvium

Gravel, sand, silt, and clay deposits of stream and river channels, and floodplains.
State Montana
Name Alluvium
Geologic age Quaternary
Lithologic constituents
Major
Unconsolidated > Coarse-detrital > Sand (Alluvial)
Unconsolidated > Coarse-detrital > Gravel (Alluvial)
Unconsolidated > Fine-detrital > Silt (Alluvial)
Minor
Unconsolidated > Fine-detrital > Clay (Alluvial)
References

Vuke, S.M., Porter, K.W., Lonn, J.D., and Lopez, D.A., 2007, Geologic Map of Montana - Compact Disc: Montana Bureau of Mines and Geology: Geologic Map 62-C, 73 p., 2 sheets, scale 1:500,000. This map was digitized in 2012 as a result of a contract between the U.S. Geological Survey and the Montana Bureau of Mines and Geology.

NGMDB product
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