USGS MR 5116, Bonita Cove, Marin Headlands (M-18B) (Cretaceous to of the United States)

Where: Marin County, California (37.8° N, 122.5° W: paleocoordinates 35.2° N, 69.7° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Valanginian to Valanginian (139.8 - 125.5 Ma)

• Assemblage MH-5: MH-5 is correlative with Valanginian to Hauterivian or early Barremian radiolarian zones in circum-Pacific onland sequences as well as with Deep Sea Drilling Project zonation schemes. The range of MH-5 is Valanginian to Hauterivian or early Barremian

• 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 185332: authorized by Matthew Clapham, entered by Matthew Clapham on 18.04.2017

Creative Commons license: CC BY (attribution)

Taxonomic list

Radiolaria
 Nassellaria - Archaeodictyomitridae
"Thanarla conica" = Thanarla brouweri
"Thanarla conica" = Thanarla brouweri Tan Sin Hok 1927 radiolarian
 Entactinaria - Saturnalidae