Where: Marin County, California (37.8° N, 122.5° W: paleocoordinates 36.6° N, 70.8° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Early/Lower Cretaceous (145.0 - 100.5 Ma)

• Cretaceous?

• bed-level stratigraphic resolution

Environment/lithology: basinal (siliceous); lithified chert

Size class: macrofossils

Reposited in the USGS

Primary reference: B. Murchey. 1984. Biostratigraphy and lithostratigraphy of chert in the Franciscan complex, Marin Headlands, California. Franciscan Geology of Northern California Field Trip Guidebook 43, Society of Economic Paleontologists and Mineralogists, Pacific Section 51-70 [M. Clapham/M. Clapham]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 185343: authorized by Matthew Clapham, entered by Matthew Clapham on 18.04.2017

Creative Commons license: CC BY (attribution)