About This Item
Share This Item
Marchand sandstone (Pennsylvanian-Missourian) oil production was discovered in 1967 at NE Verden, T8N, R8W, Grady County, Oklahoma. The play developed slowly but discoveries since 1970 by Samedan Oil Co. at Dutton townsite, Apache Corp. at NW Chickasha, and Midwest Oil Co. and Eason Oil Co. at NW Norge led to the most concentrated drilling boom in Oklahoma's Anadarko basin in recent years.
The fields are on the east flank of the east end of
the deep Anadarko basin. Production to date has been excellent. Initial potentials are more than 1,000 BOPD. Liberal allowables of up to 580 BOPD and payouts of 4-6 months for the better wells account for the rash of drilling activity.
At the end of May 1971, 74 producing wells had been completed on 160-acre spacing in a producing trend extending over 15 mi from just west of Chickasha in T6N, R8W, to Dutton townsite in T9N, R9W. There are presently 10 wells drilling to the Marchand sandstone, 5 announced locations, and 18 wells that have run production casing and are in some stage of completion. Depths range from 10,100 to 11,000 ft and drilling costs are from $100,000 to $120,000 to casing point and $180,000 to $200,000 for a completed producer.
The Marchand is a fine-grained, well-sorted sandstone and is generally highly laminated with shale. Silt and clays are found in the matrix. Regional correlations and examinations of samples, cores, and thin sections lead the writer to believe that the sandstone is of deltaic origin. The deltaic deposition apparently was complicated by channeling and offshore bar development. Regional structure at the Missourian level is relatively uncomplicated, dip being monoclinal at approximately 1°/mi toward the basin axis and interrupted only by slight nosing. The trap appears to be purely stratigraphic.
Marchand sandstone pay thicknesses range up to 125 ft. The reservoir is undersaturated and oil wet with solution gas drive. Gas/oil ratios are approximately 700 to 1 and original bottomhole pressures between 4,600 and 6,300 psi. Primary recoveries should range between 12 and 16% of the oil in place and reserves for the better wells with the thickest pay sections should be more than 750,000 bbl of oil.
The excellent production from the Marchand sandstone touched off an extensive leasing campaign in southwestern Grady and southeastern Caddo Counties, Oklahoma. The Marchand is only one of several sandstones developed in the Missourian section and chances are good that wildcat drilling will uncover additional stratigraphic production from the Missourian section in this part of the Anadarko basin.
End_of_Article - Last_Page 1688------------