The abundant coralline remains preserved in the Niagaran beds in sections five, six, and seven, Scotch Grove township, Jones County, have been strikingly pointed out by Calvin in his Geology of Jones County. In this locality the corals formed a magnificent reef and with few exceptions they are now preserved completely silicified and are imbedded in a soft dolomitic matrix which upon weathering leaves the corals among the residual products. The few corals that have not been replaced by silica occur in the form of highly crystalline limestone which upon being sectioned and polished shows the internal character of the corals fairly well. In a few cases tubular cavities in the dolomite represent the former presence of stems of colonies of Diphyphyllum, Syringopora, or others.
Proceedings of the Iowa Academy of Science
©1917 Iowa Academy of Science, Inc.
Thomas, A. O.
"A Large Colony of Fossil Coral,"
Proceedings of the Iowa Academy of Science, 24(1), 105-111.
Available at: https://scholarworks.uni.edu/pias/vol24/iss1/20