Vertical Variations of the Heavy Minerals in the Burr and Cottonwood Limestones in Riley County, Kansas

Abstract

The percentage of minerals having a specific gravity of 2.77 or more in the Cottonwood Linestone ranged layer to layer from 0.0075% to 0.073% with intermediate values around 0.02%o. In the Burr Limestone the values ranged from 0.032So to 0.046% with the shale zone hanng the lowest percentage. The following heavy minerals occur in both Cottonwood and Burr limestones: tourmaline, collophane, muscovite, zircon, garnet, hematite, magnetite and pyrite. Celestite is in the Cottonwood limestone, but is absent in the Burr Limestone. Muscovite, zircon and garnet occur in lower percentages than do the other minerals in both limestones. The magnetite content of Cottonwood Limestone was lower than that of Burr Limestone. Pyrite was in low percentage or absent from the lower parts of both limestone beds. Minerals in both limstones may have come from a common north source. Trans. Kans. Acad. Sci., 75 (3), 1972.