SILURIAN LITHOLOGY IN WESTERN TENNESSEE AND IN ADJACENT STATES
BY JOHN B. BALL
This paper presents a brief discussion of Silurian lithology in parts of western Tennessee and in certain of the adjacent States. Distinctive Silurian rock units are readily recognized in western Tennessee. They have been assembled in several formations and members by geologists. In southeast Missouri the Niagaran strata have been regarded, hitherto, as a homogeneous sequence.
In this paper emphasis is not given to stratigraphy and correlations as much as to general lithologic similarities in the regions considered. Detailed comparisons are made for western Tennessee, southern Illinois, and southeast Missouri. Lithologic aspects, such as coloration, texture, earthy admixtures, presence or absence of chert, distribution of glauconite, and the development of oölite, are considered. The persistence of certain beds and of fossil horizons is noted, where known. Some attention also is given to marked changes in the facies. . . .