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Correlation of the middle eocene Kellogg Shale of northern California

February 24, 1984

The Kellogg Shale of northern California has traditionally been considered to be late Eocene in age on the basis of benthic foraminifer, radiolarian, and diatom correlations. The 30-m-thick Kellogg section exposed west of Byron, California, however, contains middle Eocene planktonic foraminifers (Zone P12), coccoliths (Subzones CP13c and CP14a), silicoflagellates (Dictyocha hexacantha Zone), and diatoms. Quantitative studies of the silicoflagellates and diatoms show a general cooling trend through the section which is consistent with paleoclimatic trends for this part of the middle Eocene (ca. 42-45 Ma) from elsewhere in the world. Seven new silicoflagellate taxa (Corbisema angularis, C. exilis, C. hastata miranda, C. inermis ballantina, C. regina, Dictyocha byronalis, Naviculopsis americana) and one new coccolithophorid species (Helicosphaera neolophota) are described.

Citation Information

Publication Year 1984
Title Correlation of the middle eocene Kellogg Shale of northern California
DOI 10.2307/1485715
Authors John A. Barron, David Bukry, Richard Z. Poore
Publication Type Article
Publication Subtype Journal Article
Series Title Micropaleontology
Index ID 70208676
Record Source USGS Publications Warehouse
USGS Organization St. Petersburg Coastal and Marine Science Center; Volcano Science Center