Restless Kansas: Evidence of Structural Development in theFlatlands

摘要

The Phanerozoic structural development of Kansas is recorded by the stratigraphic andsedimentological evidence. The early Paleozoic was relatively quiet, but a major changein the structural regimen took place in the late Paleozoic as a result of events inadjacent areas. Structural development was mainly by vertical differential movementalong faults defining rigid Precambrian basement blocks as they adjusted to the stress.These movements are recorded in the changes of sediment thickness over the faultblocks. Concurrently, as the basement blocks adjusted, seismites were triggered bypaleoearthquakes. By mapping the occurrence of seismites vertically and laterally,conclusions can be made on the frequency and intensity of the paleoquakes. Theoccurrence of seismites formed by paleoquakes seemingly diminish with time, but thismay be a function of suitable conditions for their formation and preservation.