USGS Scientific Investigations Report 2014–5120: Digital Database of Microfossil Localities in Alameda and Contra Costa Counties, California

Digital Database of Microfossil Localities in Alameda and Contra Costa Counties, California

By Kristin McDougall and Debra Block

Abstract

The eastern San Francisco Bay region (Contra Costa and Alameda Counties, California) is a geologically complex area divided by faults into a suite of tectonic blocks. Each block contains a unique stratigraphic sequence of Tertiary sediments that in most blocks unconformably overlie Mesozoic sediments. Age and environmental interpretations based on analysis of microfossil assemblages are key factors in interpreting geologic history, structure, and correlation of each block. Much of this data, however, is distributed in unpublished internal reports and memos, and is generally unavailable to the geologic community. In this report the U.S. Geological Survey microfossil data from the Tertiary sediments of Alameda and Contra Costa counties are analyzed and presented in a digital database, which provides a user-friendly summary of the micropaleontologic data, locality information, and biostratigraphic and ecologic interpretations.

First posted September 23, 2014

Report PDF (8 MB)

Plate 1 PDF (425 KB)
Metadata
Dataset KMZ (131 KB)
Google Earth is required to view KMZ files, and can be downloaded a free of charge at http://google-earth.get-free.net/

For additional information, contact:
GMEG staff, Geology, Minerals, Energy, & Geophysics Science Center—Flagstaff
U.S. Geological Survey
2255 N. Gemini Drive
Flagstaff, AZ 86001-1600
http://geomaps.wr.usgs.gov/gmeg/

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Suggested citation:

McDougall, Kristin, and Block, Debra, 2014, Digital database of microfossil localities in Alameda and Contra Costa Counties, California: U.S. Geological Survey Scientific Investigations Report 2014–5120, 112 p., http://dx.doi.org/10.3133/sir20145120.

ISSN 2328-0328 (online)

Contents

Abstract

Introduction

Discussion of Tertiary Stratigraphy

Summary of Tertiary Stratigraphy

Acknowledgments

References Cited

Appendix—Taxonomic Notes