ABSTRACT
Several of the deep wells of Russell County, Kansas, penetrated green shales containing abundant fossils of species characteristic of the Decorah shale of the Ordovician system. These fossils are not known from any other system. The strata overlying the green shales seem to belong to the Pennsylvanian system. At any rate, strata containing Pennsylvanian fossils occur but a short distance above the green shales. The Pennsylvanian strata seem to belong to a time not older than the Douglas stage. Beneath the Ordovician green shales are several hundred feet of more or less crystalline limestones—shown as sandstones in some of the drilling logs—in which no fossils have been found. It is suggested that these limestones are of early Ordovician or Cambrian age.
