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An examination of the continental shelf in the Ventura-Port Hueneme, California, area included the collection of can cores, and vibrocores to determine the primary physical and biogenic sedimentary structure to establish a depositional-facies model.

Core analysis permits recognition of three principal zones: (1) nearshore facies (backshore to 9 m water depth), made up primarily of parallel-laminated, ripple-laminated, and cross-bedded, clean sand; bioturbation is only locally significant; (2) transition facies (9 to 18 m water depth), zone of fine sand and silty sand, characterized by an increase in biogenic over physical sedimentary structures; wave-ripple bedding and parallel lamination are important structures in this facies; (3) offshore facies (> 18 m water depth), sandy silt is the primary texture, and bioturbation is the dominant sedimentary structure; remnant parallel lamination is the only physical sedimentary structure present.

Comparison of the results of this study with a previous description of "low-energy" beach-to-offshore facies at Sapelo Island, Georgia, indicates that the two areas do not differ greatly in overall vertical sequence of sedimentary structures. The principal difference is in the thickness of the three facies: the California facies are significantly thicker than their Georgia counterparts. It is concluded that this difference is in direct response to the role of higher wave energy on the California coast.

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