The Le Claire Limestone

The Le Claire limestone constitutes the second stage of the Niagara formation as it is developed in Iowa. The first or lower stage has been called the Delaware, from the fact that all its varying characteristics are well exhibited in Delaware County. The Delaware stage embraces many barren beds and presents a very great number of phases, but at certain horizons it abounds in characteristic fossils. The typical faunas of this lower stage embrace such forms as Pentamerus oblongus Sowerby, Halysites catenulatus Linnaeus, Favosites favosus Goldfuss, Strombodes gigas Owen, Strombodes pentagonus Goldfuss, Ptychophyllum expansum Owen, and Diphyphyllum multicaule Hall. The beds of the Delaware stage furthermore contain large quantities of chert