Punchbowl Formation

The Punchbowl Formation is a sedimentary sandstone geologic formation in the northern San Gabriel Mountains, above the Antelope Valley in Los Angeles County, southern California.UCB−Seismo.berkeley.edu: Field Guide to the Punchbowl Fault Zone at the Devil's Punchbowl Natural Area . accessed 7.7.2015Punchbowl Formation at Fossilworks.org

Geology The sandstone beds of the formation are exposed in the walls of the Devil's Punchbowl, a scenic gorge within the Devil's Punchbowl Natural Area, an L.A. County park within the Angeles National Forest. Three separate faults have folded and uplifted the formation in view. The Devil's Punchbowl is a large plunging sandstone syncline, where the edges of the formation have been folded upward, and the center has dipped. It was formed by the Punchbowl Fault, which is near the San Andreas Fault to the north.

The Punchbowl Formation crops out in the Punchbowl Block and comprises approximately of fluvial and alluvial conglomerates, sandstones, and minor mudstones, which accumulated during the middle-late Miocene. A distinct basal member is middle Miocene in age. The underlying Paradise Springs and Vasquez Formations were formerly interpreted as either part of the basal Punchbowl Formation, or deposits in a fault-bounded sliver along the Punchbowl Fault that originated in a separate basin.Coffey et al., 2019, p.480

The Devil's Punchbowl drainage flows into Sandrock Creek, a tributary of Big Rock Creek, which disappears into the Mojave Desert.

Fossil content The uplifted formation preserves fossils dating back to the Neogene period of the Cenozoic geologic era, formed during the lower Pliocene to upper Miocene Ages (~5-10 million years ago).L.A. County: "Geological History", with images

Mammals Artiodactyls

Aepycamelus alexandraePagnac, 2006 Bouromeryx americanusLiter & Prothero, 2003 Brachycrus cf. buwaldi Dyseohyus fricki Pseudoparablastomeryx cf. scotti Brachycrus sp. Plioceros sp. Antilocapridae indet. Blastomerycinae indet. Camelidae indet. Merycoidodontidae indet. Tayassuidae indet.

Perissodactyls

Archaeohippus mourningi Parapliohippus cf. carrizoensis Pliohippus cf. tehonensis Scaphohippus intermontanus S. sumani Cormohipparion sp.Woodburne, 2005 ?Archaeohippus sp. Equini indet.Woodburne & Golz, 1972 Hipparionini indet. Rhinocerotidae indet.

Carnivora

Borophagus cf. secundus Leptarctus ancipidens Plionictis sp.

Rodents Petauristodon sp. Sciuridae indet.Wagner & Reynolds, 1983

Reptiles Turtles Gopherus depressus

Gallery

Punchbowl Formation

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