Palm Spring Formation

Palm Spring Formation Stratigraphic range:
Type	Geologic formation
Underlies	Vallecito Badlands
Overlies	Imperial Formation, Ocotillo Formation
Location
Region	Colorado Desert, California
Country	United States

The Palm Spring Formation is a geologic formation in the eastern Colorado Desert of Imperial County and San Diego County County, Southern California.

The Palm Spring Formation is an extensively-exposed delta-plain deposit debouched by the ancestral Colorado River across the subsiding Salton Trough. It records the development of the prehistoric Colorado River delta cone into a barrier excluding marine waters from the Salton Trough.

It preserves fossils from the Pleistocene Epoch, during the Quaternary Period of the Cenozoic Era.

Lower Pliocene sub−period petrified wood is found in Anza-Borrego Desert State Park. The Lauraceae is represented by petrified Umbellularia, the Salicaceae with petrified Populus and Salix, and the Juglandaceae with petrified Juglans.

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