Abstract

Mississippian rocks in southeastern Kansas have long been economically important because of the petroleum reserves contained in them. Rocks of Kinderhookian, Osagean, Meramecian, and Chesterian age are represented chiefly by a carbonate sequence collectively termed "Mississippi lime". The Chattanooga shale is considered with the Mississippian because of the important unconformity at the base of the unit. Thickness of the Chattanooga ranges from a featheredge to slightly more than 200 feet; thickness of "Mississippi lime" ranges from a featheredge to 450 feet.

Regional dip on the surface of Mississippian rocks in southeastern Kansas is west or slightly north of west. This homoclinal surface is interrupted by numerous minor but economically important oil-bearing structures including the Fredonia dome, Longton ridge, Beaumont anticline, and Winfield anticline. The Nemaha anticline is the dominant structural feature of southeastern Kansas; other structural trends are subordinate but nearly parallel to it. In general, structure increases with depth, crests of structures shift with depth; and the southeast flank of most northeast-trending structures is steeper than the northwest.

About 136 fields now produce from Mississippian rocks in southeastern Kansas. Box, Countryman, Posey, Weathered and Webb fields produce on closed anticlinal structures, and Albright seemingly produces from a stratigraphic trap.