Seismic Response of the East Flank of the Central Kansas Uplift, Rice County, Kansas

Abstract

A 7-mi (11.2-km) seismic line across the Lyons anticline just south of Lyons, Rice County, Kansas, shows reflections to the depth of about 3,500 ft (1,070 m) corresponding to the Precambrian Rice Formation. The Lyons anticline is used as a gas storage facility.

Although data quality of reflections from the Precambrian is poor, the indication is that the Lyons anticline existed during the Late Proterozoic and that its initial uplift may be related to Keweenawan rifting. Cambrian-Ordovician Arbuckle Group reflections diverge away from the anticline, suggesting that deposition was contemporaneous with uplift. The Middle Ordovician Simpson Group and the Devonian-Mississippian Chattanooga Shale have distinctive reflection characters. Middle and Upper Ordovician Viola and Maquoketa Formations share a single response of a strong transitional, stretched, and positive-polarity peak.

Within the Chattanooga Shale is a thin limestone member which forms a distinct positive-polarity reflection. The limestone is seen to truncate over the crest of the Lyons anticline, and apparently thins eastward and is eventually replaced with siltstone.

In the Pennsylvanian, the Kansas City, Lansing, and Douglas Groups show a reflection aspect characteristic of a deposition system that is predominantly nonmarine clastic with an associated marginal-marine transport process. Reflections in the Shawnee Group have distinctive but modes amplitude and good continuity. Existence of a possible channel is apparent in the seismic response of the Kanwaka Shale. This feature would be rare to encounter and difficult to characterize if known only from drill data. In the Wabaunsee Group, the Howard Limestone forms a very prominent reflection.

The Lower Permian Admire, Council Grove, and Chase Groups have high-amplitude continuous reflections similar to the Wabaunsee, indicating lateral consistency across the section.