Although for long it is suspected that ancestral Rocky mountains must have extended much farther to the eastward than the Front ranges of Colorado do today the actual proofs that they once did are long in forthcoming. Delay in this respect continues until oil-prospecting develops so extensively in Kansas especially. Long before these oil demonstrations the pre-Cambric crystalline basement is discovered to exist at the Missouri River much nearer to the surface than is previously thought possible. The history of this investigation is so recently given that the memoir itself may be referred to for full particulars.
Proceedings of the Iowa Academy of Science
©1930 Iowa Academy of Science, Inc.
"Easternmost Foldings of Ancestral Rockies,"
Proceedings of the Iowa Academy of Science, 37(1), 275-276.
Available at: https://scholarworks.uni.edu/pias/vol37/iss1/64