Hueneme Field: Unique Reservoir and Careful Planning Make Small California Offshore Project Profitable
C. Duane Cavit
The Hueneme field produces oil from the Miocene "Hueneme sand" and Oligocene Sespe sands along an east-west-trending anticline located on OCS Lease P-0202, 3.5 mi west of Port Hueneme in the eastern Santa Barbara Channel, California. The areal extent of the field (less than 140 ac) and the recoverable reserves (about 6 million bbl of oil) are both very small by California standards for an offshore project. A unique clastic reservoir of superior quality, along with careful predevelopment planning and engineering, have made this project an economic success and should encourage similar small offshore projects in the future.
Extensive predevelopment planning included reservoir modeling to determine number and location of producers and injectors, type of completions, and platform requirements before the setting of 15-slot Platform Gina. Six producers and five seawater injectors were drilled between late 1981 and 1982. The second development well was drilled and completed as an injector to maintain reservoir pressure. Average initial production for the six producers was 794 BOPD and peak production for the field reached 4,700 BOPD in March 1983. All wells are currently completed in Oligocene Sespe sands and in the Miocene Hueneme sand. The Sespe consists of a series of lenticular nonmarine sands and shales and contributes only about 10% of the total reserves. The Hueneme sand unconformably overlies the Sesp and reaches a maximum thickness of just over 100 ft at the top of the structure and thins in all directions off the structure. This unique reservoir consists of a massive unconsolidated arkosic sand with porosities averaging 34% and permeabilities averaging 5 darcys.
AAPG Search and Discovery Article #91035©1988 AAPG-SEPM-SEG Pacific Sections and SPWLA Annual Convention, Santa Barbara, California, 17-19 April 1988.