UW 1074A - Martinez: Ypresian, California

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Gastropoda - Heterostropha - Acteonidae
Actaeon lawsoni Weaver 1905
Gastropoda - Naticidae
Euspirocrommium martinezensis (Dickerson 1914)
original and current combination Amauropsis martinezensis
Gastropoda - Turritellidae
Turritella pachecoensis Stanton 1896
Gastropoda - Opisthobranchia - Cylichnidae
Scaphander costatus (Gabb 1864)
recombined as Scaphander (Mirascapha) costatus
Bivalvia - Lucinida - Lucinidae
? Codalucina muirensis (Dickerson 1914)
Bivalvia - Solenida - Solenidae
Solena stantoni (Weaver 1905)
recombined as Solena (Eosolen) stantoni
Bivalvia - Poromyida - Cuspidariidae
Cuspidaria hannibali Dickerson 1914
recombined as Cardiomya hannibali
Bivalvia - Cardiida - Veneridae
Pitar quadratus (Gabb 1864)
Bivalvia - Cardiida - Tellinidae
Tellina kewi Dickerson 1914
recombined as Tellina (Megangulus) kewi
Bivalvia - Carditida - Crassatellidae
Crassatella claytonensis (Dickerson 1914)
Bivalvia - Arcida - Cucullaeidae
Cucullaea mathewsoni (Gabb 1864)
original and current combination Cucullaea mathewsonii
Bivalvia - Mytilida - Mytilidae
Brachidontes ornatus (Gabb 1864)
synonym of Brachidontes (Brachidontes) cowlitzensis
unclassified
Bullinula subglobosa Weaver 1905
see common names

Geography
Country:United States State/province:California County:Contra Costa
Coordinates: 38.0° North, 122.1° West (view map)
Paleocoordinates:41.9° North, 103.6° West
Basis of coordinate:based on nearby landmark
Geographic resolution:outcrop
Time
Period:Paleogene Epoch:Eocene
Stage:Ypresian 10 m.y. bin:Cenozoic 2
Key time interval:Ypresian
Age range of interval:56.00000 - 47.80000 m.y. ago
Stratigraphy
Formation:Martinez Member:Capay Shale
Stratigraphic resolution:bed
Stratigraphy comments: From upper shale unit. Foraminifera suggest a "Capay" stage age. Capay local stage = Ypresian. 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.
Lithology and environment
Primary lithology:medium,coarse,glauconitic lithified sandy "shale"
Includes fossils?Y
Lithology description: Sandy shale
Environment:offshore
Geology comments: No environmental information reported, but fauna appears to be offshore shelf.
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils
Collection methods and comments
Collection methods:selective quarrying,field collection
Reason for describing collection:general faunal/floral analysis
Collection method comments: Collected and identified by C.E. Weaver. Collections reposited in University of Washington collections.
Taxonomic list comments:Exhaustive for Mollusca, Foraminifera, and Coelenterata. Nomenclature is somewhat antiquated, but with a high proportion of species designations.
Metadata
Database number:52614
Authorizer:A. Hendy Enterer:A. Hendy
Modifier:M. Clapham Research group:marine invertebrate
Created:2005-08-11 22:41:05 Last modified:2017-04-23 09:39:08
Access level:the public Released:2005-08-11 22:41:05
Creative Commons license:CC BY
Reference information

Primary reference:
14145. 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]