As regards origin, the cherts which occur so abundantly throughout the limestones of the lower carboniferous of the Mississippi valley have been the subject of much speculation. The same problem has received attention from every quarter of the globe. While the explanations offered differ very much from one another they in general agree in that they are regarded as formed contemporaneously with the geological formations in which they occur. The writings of Prestwich, Irving, Van Hise, Hull, Benard, Hinde, Hardman, Hovey, and many others corroborate this statement.
Proceedings of the Iowa Academy of Sciences
©1902 Iowa Academy of Science, Inc.
Keyes, Charles R.
"Genesis of Certain Cherts,"
Proceedings of the Iowa Academy of Science, 10(1), 103-105.
Available at: https://scholarworks.uni.edu/pias/vol10/iss1/17