Atlantic Margin Fields
The Foinaven Field was discovered in 1992 and is estimated to hold up to one billion barrels of oil, with the current development expecting to recover 250 million barrels. BP Amoco is the operator of the field, holding a 72% interest with Shell UK as partner. The Foinaven structure is a faulted anticline and the trapping mechanism has elements of stratigraphic pinch-out, fault and dip closure. The field is divided into five fault/stratigraphical segments with varying oil-water and gas-oil contacts. The reservoir is Paleocene in age and comprises channelized, silici-clastic turbidites, with three main oil-containing sandstone intervals. Reservoir rock varies in character from thinly interbedded sandstones to massive channel sandstone. The reservoir is good quality, fine to medium grained, with 20-30% porosity, and permeability of 500-2000 mD. The hydrocarbons are from a mixed source of Middle and Upper Jurassic mudstones. Reservoir oil is sweet with an API gravity of 26 degrees, with some wax content and relatively low viscosity. Field development was sanctioned in October 1994. Development drilling began a month later with the first oil being produced in November 1997 through the Petrojarl Foinaven floating production installation (FPSO), which is leased from and operated by Golar-Nor Offshore. Current daily production averages 80 MBOPD and cumulative oil production to end October 1999 is 50MMBBL.