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Title: Petroleum geology of Sespe field: new oil from an old field

Conference · · Am. Assoc. Pet. Geol., Bull.; (United States)
OSTI ID:6931432

The Sespe field, discovered 100 years ago, is situated along the north flank of the Ventura basin on the upthrown side of the San Cayetano fault. Production zones range from Eocene to Miocene in age and include the Matilija, Coldwater, and Vaqueros Formations. The Oligocene Sespe Formation is the primary producing zone. Fractured shale of the Miocene Rincon formation also produced but is no longer considered a target. Recent developments demonstrate how additional reserves can be established and produced from an old and nearly fully developed field. A multi-tiered exploitation program ultimately should establish significant new reserves. The field has been drilled on 10-ac spacing, but several recently drilled wells demonstrated that production can be enhanced by infill drilling on 5-ac spacing. The infill wells not only decrease recovery time of proved reserves, but also increase the recoverability of in-place oil from 9% to about 14%. Waterflooding may enhance recoverability even further. After at least nine infill patterns have been drilled, a pilot waterflood project has been planned to determine if displacement can be conducted economically. The authors believe the incremental increase in recoverable reserves of the projects discussed may ultimately exceed all the petroleum produced in the past 100 years. The Sespe field serves as an example of an example of an old field that can be made to yield important new reserves at relatively low risk.

Research Organization:
Argo Petroleum Corporation, Venture, CA
OSTI ID:
6931432
Report Number(s):
CONF-8604187-
Journal Information:
Am. Assoc. Pet. Geol., Bull.; (United States), Vol. 70:4; Conference: American Association of Petroleum Geologist Pacific Section convention, Bakersfield, CA, USA, 16 Apr 1986
Country of Publication:
United States
Language:
English