Also known as USGS #18983; Field #S25

Where: Orange County, California (33.9° N, 117.7° W: paleocoordinates 37.5° N, 98.2° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

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

• 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.

• bed-level stratigraphic resolution

Environment/lithology: marine; fine-grained, medium sandstone

Size class: macrofossils

Reposited in the USGS

Collection methods: quarrying,

• Collected by J.E. Schoelhamer. Material likely to be reposited in USGS Menlo Park collections or USNM.

Primary reference: 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]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 52596: authorized by Austin Hendy, entered by Austin Hendy on 11.08.2005

Creative Commons license: CC BY (attribution)