Simpson Filled Sinkholes in Eastern Kansas

Abstract

Six sinkholes involving rocks of Simpson age (Ordovician) were found from examination of logs of wells drilled in eastern Kansas. These sinks contain abnormally thick Simpson sediments, chiefly St. Peter sandstone, which is interpreted as having been deposited as fill in sinkholes developed on an eroded surface of dolomite and limestone of the Arbuckle group. Chert conglomerate and green shale are present in the bottom of the sinks. The shale consists mainly of an illitic clay and quartz, which may be residual weathering products formed in place or washed into the sinks. It is believed that these subsurface features are similar to the Otterville structure in Cooper County, Missouri.