Gulf of California section 2 "unconformity (upper)" fauna (Pleistocene of Mexico)

Also known as Section 2 - unconformity (upper) shell bed type

Where: Sonora, Mexico (31.8° N, 114.1° W: paleocoordinates 31.8° N, 114.1° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Late/Upper Pleistocene (0.1 - 0.0 Ma)

• Pleistocene fluvial, eolian, and deltaic deposits exposed in sea cliffs, overlain by coquina bed (dated at 125,00 bp)

• bed-level stratigraphic resolution

Environment/lithology: transition zone or lower shoreface; unlithified, burrowed, bioturbated, fine-grained, medium sandstone and siltstone

• active trans-tensional rift basin
• massive fine- to medium-grained sands; bedding almost obscured by bioturbation; bedding mostly planar or low-angle corss-stratified, rare wavy beds and reactivation cross-beds; Ophiomorpha and Thalassinoides burrows common; burrows backfilled with shelly debris; Skolithos rare to common

Size class: macrofossils

Collection methods: bulk,

• No comments on collection metholodolgy

Primary reference: K.H. Meldahl and A. H. Cutler. 1992. Neotectonics and taphonomy; Pleistocene molluscan shell accumulations in the northern Gulf of California. Palaios 7(2):187-197 [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: taphonomic analysis

PaleoDB collection 34936: authorized by Austin Hendy, entered by Austin Hendy on 20.10.2003

Creative Commons license: CC BY (attribution)

Taxonomic list

• No abundance data given on collection due to poor preservation
Cirripedia indet. barnacle
Listed as "barnacle plates"
Bivalvia indet. Linnaeus 1758 clam
Listed as "unidentifiable bivalves"
 Pectinida - Pectinoidae
Pectinidae indet. Wilkes 1810 scallop
Listed as "scallop fragments"
 Ostreida - Ostreidae
Ostrea sp. Linnaeus 1758 oyster
 Cardiida - Veneridae
Chione californiensis Broderip and Sowerby I 1835 venus clam
"Chione gnidia" = Chionopsis gnidia Broderip and Sowerby I 1829 venus clam
 Cardiida - Cardiidae
Trachycardium sp. Mörch 1853 cockle
 Neogastropoda - Columbellidae
Columbella sp. Lamarck 1799 snail
 Trochoidea - Tegulidae