thumbnail

Neogene folding and faulting in southern Monterey Bay, Central California, USA

Marine Geology

By:
, ,

Links

  • The Publications Warehouse does not have links to digital versions of this publication at this time

Abstract

The goal of this study was to determine the Neogene structural history of southern Monterey Bay by mapping and correlating the shallow tectonic structures with previously identified deeper occurring structures. Side scan sonographs and Uniboom seismic reflection profiles collected in the region suggest that deformation associated with both compressional and transcurrent movement is occurring. Strike-slip movement between the North American and Pacific plates started as subduction ceased 21 Ma, creating the San Andreas fault system. Clockwise rotation of the Pacific plate occurred between 3.4 and 3.9 Ma causing orthogonal convergence between the two plates. This plate rotation is responsible for compressional Neogene structures along the central California coast. Structures exhibit transpressional tectonic characteristics such as thrust faulting, reverse faulting and asymmetrical folding. Folding and faulting are confined to middle Miocene and younger strata. Shallow Mesozoic granitic basement rocks either crop out or lie near the surface in most of the region and form a possible de??collement along which the Miocene Monterey Formation has decoupled and been folded. Over 50% of the shallow faults strike normal (NE-SW) to the previously identified faults. Wrench fault tectonics complicated by compression, gradual uplift of the basement rocks, and a change in plate convergence direction are responsible for the observed structures in southern Monterey Bay. ?? 1993.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Neogene folding and faulting in southern Monterey Bay, Central California, USA
Series title:
Marine Geology
Volume
113
Issue:
3-4
Year Published:
1993
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
First page:
163
Last page:
177
Number of Pages:
15