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 185297: authorized by Matthew Clapham, entered by Matthew Clapham on 18.04.2017
Creative Commons license: CC BY (attribution)
Taxonomic list
Protozoa | |
Zifondium sp., "Thanarla conica" = Thanarla brouweri, Archaeodictyomitra simplex, "Archaeodictyomitra apiaria" = Archaeodictyomitra apiarium
Zifondium sp. Pessagno 1977 radiolarian
"Thanarla conica" = Thanarla brouweri Tan Sin Hok 1927 radiolarian
Archaeodictyomitra simplex radiolarian
"Archaeodictyomitra apiaria" = Archaeodictyomitra apiarium Rüst 1885 radiolarian | |
Pseudodictyomitra "sp. A" Pessagno 1977 radiolarian | |
Mirifusus ? mediodilatatus Rüst 1885 radiolarian | |
Podobursa "sp. A" Wisniowski 1889 radiolarian | |
Acanthocircus dicranocanthos radiolarian | |
Cecrops septemporata radiolarian |