ABSTRACT: West Chalkley, Cameron Parish, Louisiana--A Case for Continued Exploration in Mature Producing Provinces

G. E. Klefstad

A potential giant gas field has been discovered in the very mature exploration province of south Louisiana by Transco Exploration Partners (TXP) and Exxon Company U.S.A. The West Chalkley prospect is located in Cameron Parish, Louisiana, and is productive in the upper Oligocene Miogypsinoides (Miogyp) sandstones. The discovery is in the same producing trend as the prolific South Lake Arthur field, where the Miogyp sandstones have gas reserves on the order of 1.0 tcf.

The prospect was generated by a combination of trend analysis, subsurface well control, and reflection seismic data. The feature appears to be a faulted anticline separate from the nearest production in the area, Chalkley field, which is located about 1 mi east and discovered in 1938.

Both TXP and Exxon, working independently, recognized the potential prospect and pursued leasing activities in the area. TXP initiated discussions with the landowner in February 1988 and acquired a 960 ac lease in June. Exxon leased approximately 2100 ac surrounding the TXP lease about one month later. TXP subsequently sold the prospect to Exxon on October 12, 1988. The Exxon 1 Sweet Lake Land and Oil Company was spudded on March 16, 1989, and reached total depth of 15,600 ft on July 4, 1989. Log analysis indicated nearly 500 net ft of gas pay in the 805-ft gross productive interval. Testing through perforations near the base of the pay zone yielded flow rates as high as 21.28 MMCFGPD and 338 BOPD. The discovery well is expected to be on production by early 1990 at rates approaching 5 MMCFGPD. Two delineation wells are currently drilling and a deeper pool wildcat is planned to spud around mid-1990 to determine the areal extent and ultimate size of this important new find.

AAPG Search and Discovery Article #91000©1990 AAPG Conference-Giant Oil and Gas Fields of the Decade 1978-1988 Conference, Stavanger, Norway, September 9-12, 1990