Surface geology of the northern Midway-Sunset Field and adjacent Temblor Range, Kern County, California
- Santa Fe Energy Resources, Bakersfield, CA (United States); and others
New surface mapping at a 1:12000 scale adjacent to the 2 billion barrel Midway Sunset Field has revealed complex intraformational stratigraphy within the upper Miocene Santa Margarita Formation (Tms). Locally known as the Potter and Spellacy Formations in the subsurface, these sandstone and conglomerate heavy oil reservoirs produce the majority of Midway Sunset daily production of 164,000 barrels of oil via thermal EOR processes. The Tms consists mostly of conglomerate inserted into the Belridge Diatomite (Tmb) interval. The stratigraphically lower intervals of the Tms clearly fill deeply incised valleys or submarine canyons cut into Tmb and locally into the underlying Antelope Shale (Tma). The basal intervals of Tms; are very coarse grained, containing boulders of granitic and metamorphic rock as large as 4 meters that were derived from the Salinian block west of the San Andreas Fault. The upper intervals of Tms are more sheet-like and interbedded containing clasts less than 50 cm in length. The incised valleys have a spacing of about one mile in outcrop, with a gap located in the area of the older Republic Sandstone (Tmr). Paleocurrents from Tms regionally suggest sediment transport to the northeast. The sedimentary structures of Tms suggest deposition in deep-water conditions, probably a slope (bathyal) setting. Shelf environments should have been present to the southwest (now stripped away by erosion) and submarine-fan and basin-floor environments to the northeast.
- OSTI ID:
- 6574494
- Report Number(s):
- CONF-960527-; CODEN: AABUD2
- Journal Information:
- AAPG Bulletin, Vol. 5; Conference: Annual convention of the American Association of Petroleum Geologists, Inc. and the Society for Sedimentary Geology: global exploration and geotechnology, San Diego, CA (United States), 19-22 May 1996; ISSN 0149-1423
- Country of Publication:
- United States
- Language:
- English
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[open quotes]2-Step[close quotes] log analysis of the Spellacy reservoir in the giant Midway-Sunset Field, Kern County, California
{open_quotes}2-Step{close_quotes} log analysis of the Spellacy reservoir in the giant Midway-Sunset Field, Kern County, California