UW 2540 - Potrero Hills (Paleocene of the United States)

Where: Solano County, California (38.2° N, 122.0° W: paleocoordinates 43.4° N, 101.0° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Martinez Formation, Thanetian (59.2 - 56.0 Ma)

• Most of the fossiliferous faunas in the sections near Martinez occur in the lower 800 ft thick sandstone unit. Mollusca suggest a "Martinez" stage age. Martinez local stage = Thanetian. The Martinez Formation rests with a slight unconformity on the Chico Formation and grades in Eocene shales. The formation is approximately 3100 ft thick with a 1500 ft lower sandstone unit and 1600 ft upper sandy shale, which is dated as Early Eocene.

• bed-level stratigraphic resolution

Environment/lithology: offshore; poorly lithified, medium-grained, coarse, glauconitic sandstone

• No environmental information reported, but fauna appears to be offshore shelf.
• Massive, medium- and coarse-grained sandstones, in part glauconitic.

Size class: macrofossils

Collection methods: quarrying,

• Collected and identified by C.E. Weaver. Collections reposited in University of Washington collections.

Primary reference: C. E. Weaver. 1949. Geology of the coast ranges immediately north of the San Francisco Bay region, California. Geological Society of America Memoir 35 [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 52618: authorized by Austin Hendy, entered by Austin Hendy on 11.08.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

• Exhaustive for Mollusca, Foraminifera, and Coelenterata. Nomenclature is somewhat antiquated, but with a high proportion of species designations.
Gastropoda
 Sorbeoconcha - Naticidae
Polinices hornii, "Euspirocrommium martinezensis" = Amauropsis martinezensis
Polinices hornii Gabb 1864 moon snail
"Euspirocrommium martinezensis" = Amauropsis martinezensis Dickerson 1914 moon snail
 Neogastropoda - Muricidae
"Perissolax tricarinatus" = Pseudoperissolax tricarnatus
"Perissolax tricarinatus" = Pseudoperissolax tricarnatus Weaver 1905 murex snail
 Sorbeoconcha - Ficidae
"Priscofusus robustus" = Priscoficus robustus
"Priscofusus robustus" = Priscoficus robustus Weaver 1905 fig shell
 Cerithioidea - Turritellidae
Turritella infragranulata Gabb 1864 turret shell
Turritella pachecoensis Stanton 1896 turret shell
Bivalvia
 Nuculida - Nuculidae
Acila (Truncacila) decisa Conrad 1855 divaricate nutclam
 Arcida - Glycymerididae
Glycymerita major Stanton 1896 clam
Subspecies: Glycymeris veatchii major
 Pectinida - Limidae
"Lima multiradiata" = Acesta (Acesta) multiradiata
"Lima multiradiata" = Acesta (Acesta) multiradiata Gabb 1869 file clam
 Mytilida - Mytilidae
"Volsella merriami" = Modiolus (Modiolus) merriami
"Volsella merriami" = Modiolus (Modiolus) merriami Weaver 1905 mussel
 Cardiida - Veneridae
Pitar quadratus Gabb 1864 venus clam
 Cardiida - Cardiidae
"Nemocardium linteum" = Nemocardium (Nemocardium) linteum
"Nemocardium linteum" = Nemocardium (Nemocardium) linteum Conrad 1855 cockle
 Cardiida - Tellinidae
""Tellina" undulifera" = Tellina (Saulella) undulifera, "Tellina martinezensis" = Tellina (Eurytellina) martinezensis
""Tellina" undulifera" = Tellina (Saulella) undulifera Gabb 1869 tellin clam
"Tellina martinezensis" = Tellina (Eurytellina) martinezensis Weaver 1905 tellin clam
 Solenida - Solenidae
"Solena stantoni" = Solena (Eosolen) stantoni
"Solena stantoni" = Solena (Eosolen) stantoni Weaver 1905 clam