Geologic map of the Elysian Park-Silver Lake District: Supplement 1 from "Geology of the Elysian Park-Silver Lake District, Los Angeles County, California" (Thesis)

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This is a report on the general geology of the Elysian Park-Silver lake district; a six square mile tract of hilly country lying just north of the city of Los Angeles. The rock units present are granitio bedrock of Jurassic(?) age, sediments of Tertiary age and Quaternary alluvium. The bedrock is a granodiorite; the Tertiary beds which are divided into the Topanga of middle Miocene and Modelo of upper Miocene ages are made up of sandstone and shale; and the Quaternary alluvium consists of reworked Tertiary and granitic bedrock detritus. The main structural feature over most of the area is a wide east-west anticline. A few extensive faults and a great many minor faults occur, all of which dip at a high angle. The geologic history of the area began with the intrusion of the granitic bedrock. The area was then extensively eroded exposing the bedrock to the surface. Then followed the unconformable deposition of the Topanga formation, followed by folding and faulting. Later unconformable deposition of the Modelo occurred, followed by more folding and faulting. There is a time break between upper Miocene and upper Pleistocene in sedimentation. In upper Pleistocene time alluvial fans were deposited over the northern part but later partially eroded off to give present landscape.

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