F88 - Silverado Formation, Santa Ana Mountains: Thanetian, California

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Bivalvia - Cardiida - Veneridae
? Pitar cf. stantoni
Bivalvia - Lucinida - Lucinidae
? Claibornites cf. turneri (Stanton 1896)
Bivalvia - Arcida - Glycymerididae
Glycymeris cf. veatchii (Gabb 1864)
Subspecies: Glycymeris veatchii major
    = Glycymerita major Stanton 1896
Hendy 2020
Gastropoda - Neogastropoda - Fasciolariidae
? Streptolathyrus sp. (Cossmann 1901)
original and current combination Streptochetus (Streptolathyrus)
Gastropoda - Turritellidae
Turritella cf. pachecoensis Stanton 1896
see common names

Geography
Country:United States State/province:California County:Orange
Coordinates: 33.9° North, 117.7° West (view map)
Paleocoordinates:37.5° North, 98.2° West
Basis of coordinate:based on nearby landmark
Altitude:265 meters
Geographic resolution:outcrop
Time
Period:Paleogene Epoch:Paleocene
Stage:Thanetian 10 m.y. bin:Cenozoic 1
Key time interval:Thanetian
Age range of interval:59.20000 - 56.00000 m.y. ago
Stratigraphy
Formation:Silverado
Local section:Gypsum Canyon
Regional section:Los Angeles
Stratigraphic resolution:bed
Stratigraphy comments: The type section suggests a thickness of around 350 m for the Silverado Formation, which lies unconformably upon the Late Cretaceous Williams Formation and Ladd Formation, and is overlain unconformably by the Santiago Formaton. The Silverado Formation is given a Paleocene age on the basis of macrofauna (sparse index taxa), but more finely assigned by McCulloh et al. (2000) to the Martinez stage = Thanetian. Calcareous nannoplankton zone CP7-CP; Planktonic foraminifera zone P4-P5; Ynezian foram zone. The Silverado Formation is correlative to the lower-middle Santa Susana Formation. From uppermost marine fossiliferous part of formation.
Lithology and environment
Primary lithology:fine,medium,shelly/skeletal sandstone
Includes fossils?Y
Lithology description: Fine-medium grained sandstone. Listed as a "shelled"
Environment:marine indet.
Glacial or sequence phase:transgressive
Geology comments: The contact below the Silverado Formation represents an episode of deformation and extensive erosion and deep weathering between the deposition of the late Cretaceous rocks and the Paleocene strata.
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils
Collection methods and comments
Collection methods:selective quarrying,field collection,survey of museum collection
Reason for describing collection:biostratigraphic analysis
Museum repositories:USGS
Collection method comments: Collected by J.E. Schoelhamer. Material likely to be reposited in USGS Menlo Park collections or USNM.
Taxonomic list comments:Fossils identified by Stewart (1954, 1955) and Moore (1959). Relatively good nomenclature
Metadata
Also known as:USGS# 18984; Field# S42
Database number:52598
Authorizer:A. Hendy Enterer:A. Hendy
Modifier:A. Hendy Research group:marine invertebrate
Created:2005-08-11 21:05:45 Last modified:2013-11-25 13:37:23
Access level:the public Released:2005-08-11 21:05:45
Creative Commons license:CC BY
Reference information

Primary reference:
3060. J. E. Schoellhamer, J. G. Vedder, R. F. Yerkes and D. M. Kinney. 1981. Geology of the Northern Santa Ana Mountains, California. United States Geological Survey Professional Paper 420(D):1-109 [J. Alroy/J. Alroy/R. McClees-Funinan]

Secondary references:

63217 A. J. W. Hendy. 2020. Unpublished taxonomic backbone for Eastern Pacific Invertebrate Communities of the Cenozoic (EPICC) Thematic Collections Network. [A. Hendy/A. Hendy/A. Hendy]