A year ago I attempted to emphasize the importance of having definite and absolute datum-planes for purposes of exact geological correlation, and I endeavored to show that stratigraphic unconformities have a far greater significance than is usually ascribed to them, especially when viewed in the light of modern physiographic principles. The latter not only imply the recognition of peneplains, or stages of approximate base-level of the land surface, but also in the sea areas the equivalent representatives in certain deposited materials. The cause inducing the new cycle of deposition being the same as that which produces mountains, the method of stratigraphical correlation based upon it was termed orotaxis, or classification of geological formations by mountain development.
Proceedings of the Iowa Academy of Sciences
©1897 Iowa Academy of Science, Inc.
Keyes, Charles R.
"Geographic Development of the Crimea,"
Proceedings of the Iowa Academy of Science, 5(1), 52-54.
Available at: https://scholarworks.uni.edu/pias/vol5/iss1/10