Skip to Main Content
Book Chapter

Hydrocarbon Potential of Northern and Central California Offshore

By
Ernest G. Hoskins
Ernest G. Hoskins
Search for other works by this author on:
John R. Griffiths
John R. Griffiths
Search for other works by this author on:
Published:
January 01, 1971

Abstract

The continental shelf appears to have a granite basement from Point Conception to about Point Arena and a metasedimentary type of basement from Point Arena to the Oregon border. Remnants of thick marine Cretaceous and Eocene sections are present throughout the length of the shelf, but because of their erosional history, the poor potential for reservoirs, and the difficulties in mapping, they appear to merit little further exploration. Deep-marine beds deposited throughout the length of the shelf from early Miocene through early late Pliocene time appear to have by far the best potential for hydrocarbon reserves. This section generally includes thick sequences of shale and ample reservoir-quality sandstone. Hydrocarbon shows are common. The overlying Pleistocene beds are not considered as objectives.

The six basins present on the shelf, each of which has an onshore extension, began forming in late middle Miocene time. Generally they do not contain as thick a post-Eocene section as that in the producing onshore California basins.

The southern third of the offshore Santa Maria basin is similar to the onshore part and is considered to have about the same hydrocarbon potential; the northern two thirds is only slightly explored. The Outer Santa Cruz basin lacks large, mappable structural traps and extensive reservoir-quality sandstone beds; however, oil shows are common. The offshore half of the small Santa Cruz basin is considered to have about the same hydrocarbon potential as the onshore half, where production is minor. The Bodega and Point Arena basins contain most of the geologic constituents of major producing basins, but they also have 16 structurally well-located dry holes. Eel River basin, the largest and least explored of the shelf basins, has good structural- trap potential, and limited data suggest the presence of an objective Miocene-Pliocene section, but beneath deep water.

You do not currently have access to this article.

Figures & Tables

Contents

AAPG Memoir

Future Petroleum Provinces of the United States—Their Geology and Potential, Volumes 1 & 2

Ira H. Cram
Ira H. Cram
Search for other works by this author on:
American Association of Petroleum Geologists
Volume
15
ISBN electronic:
9781629812236
Publication date:
January 01, 1971

GeoRef

References

Related

Citing Books via

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal