Abstract: Burning Shale and Chalk Deposits Along Missouri Trench in South Dakota

J. C. Harksen, R. N. Helgerson, R. L. Stach, M. J. Tipton

Recent discoveries of burning shale and chalk deposits along the Missouri trench near Chamberlain, South Dakota, have raised questions regarding the potential of these deposits as a commercial energy source. Three sites have been reported actually burning, and an additional 16 clinker bed sites have been found; only one is on fire.

The active burn site is approximately 2 mi south of Chamberlain, South Dakota, at the contact of the organic-rich Niobrara Chalk and Sharon Springs Member of the Pierre Shale (Late Cretaceous). The burn is contained in a slump block approximately 200 ft long by 60 ft high.

A line of fissures near the top of the slump is actively emitting steam, hydrogen sulfide, and other gaseous products. The fissures are rimmed with native sulfur and in some cases heavy tar. During peak activity, rock temperatures at the mouth of the fissures were measured at greater than 360°C. Probably the burn is maintained by the distillation and combustion of hydrocarbons from the surrounding rock. The Sharon Springs-Niobrara interval was cored approximately one-fourth mi from the burn site to obtain weathered samples for analyses.

AAPG Search and Discovery Article #90979©1975 AAPG – SEPM Rocky Mountain Sections Annual Meeting, Albuquerque, New Mexico