Geologic units containing alluvial fan

Earth material > Unconsolidated material > Alluvium

Alluvial fan

A low, outspread, relatively flat to gently sloping mass of loose rock material, shaped like an open fan or a segment of a cone, deposited by a stream (esp. in a semiarid region) at the place where it issues from a narrow mountain valley upon a plain or broad valley...

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Idaho - Oregon - Texas

Idaho

Gravel, sand, and clay; Quaternary-Tertiary colluvium and fanglomerate; western Idaho (Pleistocene and Pliocene): Pleistocene and Pliocene fanglomerate, colluvium, and poorly sorted gravel deposits.
Gravel, sand, and silt; glacial outburst flood deposits, outwash, fanglomerate, and alluvium, undivided; Pleistocene (Pleistocene): Pleistocene outwash, fanglomerate, flood and terrace gravels; sudivisions are: (Qpug, Qpmg, and Qplg).
Gravel, sand, and silt; Quaternary; alluvium (Quaternary): Quaternary alluvium; may contain some glacial deposits and colluvium in uplands
Gravel, sand, and silt; Quaternary basin-filling alluvium; Snake River Plain, Basin and Range provinces (Quaternary): Quaternary detritus; generally basin-filling deposits of central and southern Idaho.

Oregon

Fanglomerate (Holocene? and Pleistocene) (Pleistocene to Holocene): Poorly sorted and poorly stratified alluvial fan debris, slope wash, colluvium, and talus; composed mostly of silt and fragments of basalt, basaltic andesite, and andesite. In places includes small areas of pediment gravels and colluvium

Texas

alluvial fan deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene): alluvial fan deposits

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