USGS M5154, Ano Nuevo Creek (Miocene to of the United States)

Where: San Mateo County, California (37.1° N, 122.3° W: paleocoordinates 36.8° N, 120.7° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Sandstone Member (Purisima Formation), Messinian to Messinian (7.2 - 3.6 Ma)

• Purisima Formation in its type area is as much as 1725 m thick; Diatom floras in Purisima Fm are diagnostic of a late Miocene and early Pliocene age.

• bed-level stratigraphic resolution

Environment/lithology: offshore; diatomaceous, tuffaceous, gray, yellow siltstone and volcaniclastic, gray, blue sandstone

• Upper Miocene to Pliocene sedimentary sequence consisting of shallow water transgressive sandstone (Santa Margarita Sandstone), and the deep water siliceous organic mudstone unit (Santa Cruz Mudstone) and a shallow water unit (Purisima Fm).
• Very thick-bedded yellowish-gray tuffaceous and diaotomaceous siltstone with thick interbeds of bluish-gray semifriable andesitic sandstone.

Size class: macrofossils

Reposited in the UMMP

Collection methods: quarrying,

• Also collections at USGS, Menlo Park

Primary reference: J. C. Clark. 1981. Stratigraphy, paleontology, and geology of the Central Santa Cruz Mountains, California Coast Ranges. United States Geological Survey Professional Paper 1168:1-51 [A. Miller/A. Hendy/R. McClees-Funinan]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 37554: authorized by Austin Hendy, entered by Austin Hendy on 16.03.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Single mention of an echinoid taxon
 Clypeasteroida - Dendrasteridae
Dendraster gibbsi sand dollar