2005 Salt Lake City Annual Meeting (October 16–19, 2005)

Paper No. 4
Presentation Time: 1:30 PM-5:30 PM

RED BEDS! COAL! PLANT FOSSILS! NEWLY DESCRIBED STRATA FROM MICHIGAN'S “MISSING TIME” INTERVAL


KNAPP, Jonathan P. and BENISON, Kathleen C., Geology, Central Michigan University, 314 Brooks Hall, Central Michigan University, Mt. Pleasant, MI 48859, knapp1jp@gmail.com

Previously unknown and undescribed sedimentary strata, including red and grey shales, sandstones, and coal, have been discovered in an outcrop in Saginaw, Michigan. Fissile red shales and very fine-grained laminated and cross-laminated sandstones predominate, but coal and massive siltstones and mudstones are also present. Besides the coal, the rocks are various shades of red and grey with spots of high-intensity red and areas that appear to be reduction spots. Several varieties of plant fossils are abundant and well preserved. Some paleosol features such as rhizoliths and cracking are found. Preliminary fossil identification and stratigraphic position suggest a post-Mississippian age. These strata are dissimilar to the few documented post-Mississippian rocks in Michigan, including the Pennsylvanian Grand River and Saginaw Formations and the Jurassic Ionia Formation. Further investigation of theses new strata may lead to a better understanding of Michigan's paleoenvironment during its “missing time” interval of Permian-Tertiary