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Age and correlation of the Calera Limestone in the Permanente terrane of northern California

January 1, 1992

Planktonic foraminifers indicate that outcrops of Calera Limestone from the Permanente terrane in the Franciscan Complex of northern California range in age from possibly as old as Barremian to late Turonian. Underlying black limestone, which is devoid of planktonic foraminifers, presumably is Barremian in age or older. The top of the sequence exposed in major quarries is always faulted. Improved biostratigraphic resolution shows two patterns of missing time intervals. The primary pattern, which is found at all localities and involves missing planktonic foraminiferal zones in the late Aptian to early Albian and the late Albian, is linked to paleoceanographic changes in the Cretaceous Pacific Ocean. The secondary pattern, which is found at the scattered outcrops outside the major quarries and involves missing zones in the Albian and Cenomanian, suggests the results of a common tectonic history related to the accretion of a large seamount.

Publication Year 1992
Title Age and correlation of the Calera Limestone in the Permanente terrane of northern California
DOI 10.3133/ofr92306
Authors William V. Sliter, Mary McGann
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Open-File Report
Series Number 92-306
Index ID ofr92306
Record Source USGS Publications Warehouse