Mechanical-Production Aspects of the Rincon Island Development

Since its completion in Sept., 1958, Richfield Rincon island has been the site of intense drilling activity. The score thus far on the 1-acre, rock-base island is three wells completed, a fourth in the process of being drilled, and facilities for the ultimate drilling of 58 more wells. The lease being developed by the Richfield Rincon island is 1,175 acres in areal extent and lies south and west of Punta Gorda, 10 miles north of the city of Ventura and is in the western portion of the Rincon field (see Fig. 1). The location of the island was based on geologic information obtained from core holes drilled from the Rincon barge, a converted LSM. The island is located approximately 3,000 ft southwest of Punta Gorda in 45 ft of water. At the present time there are four types of structures being used to develop California offshore oil leases:template-type platform,permanent platform,floating barge, andartificial island. There are currently two artificial islands off the California Coast, the Monterey-Texas island at Seal Beach and the Richfield Rincon island. Both of these islands were constructed to develop state leases granted under the California Tidelands Law as it existed prior to Sept., 1955. The law, which has since been modified, at that time called for development from upland sites or from filled lands. Island Scientifically Designed The first step in the design of the island was a detailed study of prevailing winds, surface currents and wave heights. The worst weather month was found to be January, at which time the waves are below 5 ft in height 90 per cent of the time and over 16.5 ft 0.1 per cent of the time. However, waves of the order of magnitude of 25 to 30 ft have been observed in this area. The direction of waves is from N 80° W to S 60° W. Prevailing winds are from the northwest at 8 to 12 mph. Using this weather data, model studies were made of various types of island structures at the Army Corps of Engineers Waterways Experimental Station at Vicksburg, Miss., and from these studies evolved the basic island design. The design can be briefly described as a rock revetment with an internal sand core and with protective armor rock on the outside (see Fig. 2).