Pg. 680, 683. Converse sand (informal). Name applied to oil-producing zone at top of Minnelusa formation in Lance Creek oil field, Niobrara County, Wyoming. Immediately underlies Permian Opeche formation. [Age is Pennsylvanian.]
[Probably named from Ohio Oil Company, Converse Sheep No. 5 well, in SE/4 SW/4 sec. 32, T. 36 N., R. 65 W., Niobrara Co., northeastern WY.]

Source: Publication; GNU records (USGS DDS-6; Denver GNULEX).

Extends name, and gives thickness and shows stratigraphic position within the Minnelusa formation in representative sections for the Dewey Dome oil field, Weston Co, and the Mule Creek and Lance Creek oil fields, Niobrara Co, WY, Powder River basin. Distinguishes the first Converse sand at the top of the formation in all three oil fields, and the second Converse sand in the upper part of the formation in the Dewey Dome and Mule Creek oil fields. First Converse sand shown as sandstone 55 ft thick in the representative section for the Lance Creek field. Second Converse sand is sandstone 70 ft and 15 ft thick, and 275 and 325 ft below the top of the formation, in the Dewey Dome and Mule Creek fields, respectively. Pennsylvanian in age.

Source: GNU records (USGS DDS-6; Denver GNULEX).

Extends name from Niobrara Co, WY northwestward into Fall River and Custer Cos, SD, in the Powder River basin and on the Chadron arch. Is a sandstone bed or zone at the top of the Minnelusa formation. Permian in age.

Source: GNU records (USGS DDS-6; Denver GNULEX).

[Informal] Converse sands in Cassa group (Division I) in Hartville formation. Two main bodies of sandstone (upper and lower Converse sands) separated by dolomite and anhydrite sequence. Sandstones are eastward tongues of the Casper formation. Age is Early Permian, possibly lower Middle Permian.
Present in subsurface of Niobrara, Platte, and Goshen Counties, Wyoming, and Fall River County, South Dakota.

Source: Modified from GNU records (USGS DDS-6; Denver GNULEX).

Revised as a formal unit, the Converse Formation; was previously considered an informal term--Converse sand at the top of the Minnelusa Formation--by Hunt (1938). [No change indicated by author of use or stratigraphic rank of the Minnelusa]. Occurs in subsurface of North Hollingsworth field which is located on the southwest flank of the Black Hills uplift in Fall River Co, SD, on the Chadron arch. Covers approximately 160 acres in secs 19 and 20, T10S, R1E, Fall River Co. Divided into (upward): 3rd anhydrite, lower Converse, 2nd anhydrite, upper Converse, and first anhydrite in North Hollingsworth Federal #1 in T10S, R1E. Stratigraphic section. Structure map. Cross sections. Isopach map of lower Converse. Underlies Opeche Shale; is separated from Leo Formation (revised) by a distinctive thin shale unit called Red Shale marker. Is of Permian age.

Source: GNU records (USGS DDS-6; Denver GNULEX).