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This view is looking east from Painted Rock toward the Temblor Range.
The trace of the San Andreas Fault and northern Elkhorn Hills escarpment
are midway across the right side of the image about halfway across the
valley.
The Temblor Range and surrounding region contains extensive outcrops
of the Monterey Formation (Miocene age, about 20 to 9 million years).
Rocks from the Monterey formation consist mostly of silaceous shales and
porcellanite (silica derived from fossil plankton in an intermediate to
deep-water marine setting). Fossils and sediments from the Monterey Formation
show that the Carrizo Plain region was a marine basin with shallow to
intermediate depths (marine waters covered the southern San Joaquin Valley
region). Marine sediments younger than about 9 million years are not preserved
in the park area, but they occur throughout the Kettleman Hills region
(about 60 miles north of the park) where the Etchegoin Formation contains
marine fossils to about 4 million years old (Pliocene Epoch). Fossils
of the Etchegoin Formation are supporting evidence that the Coast Ranges
and the Temblor Range are young, having been uplifted mostly during the
Pleistocene Epoch (or Quaternary Period) in the past couple million years.
Much of that ongoing uplift is associated with tectonics associated with
the San Andreas Fault and other fault systems in the region.
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