The intracratonic Michigan Basin is located between the distal margin of the Appalachian foreland, the eastern edge of the Illinois basin, and the southern boundary of the Canadian Shield. Late Paleozoic strata (Mississippian-Pennsylvanian) of the Michigan Basin are primarily coarse siliciclastic and represent the last preserved relict of fluvial-deltaic sedimentation coeval with Alleghenian orogenesis in the continental interior. Previous studies suggest that these strata were derived from source areas associated with the Appalachian orogen; however, the timing and spatial distribution of Appalachian depositional systems throughout eastern North America is the topic of ongoing debate. Summarized here are new provenance data from the Carboniferous strata of the Michigan Basin, including detrital framework modes, previously reported and newly compiled heavy mineral analyses, and the first set of U-Pb detrital zircon ages (n=431) from the Carboniferous strata in Michigan. Provenance trends from the Early Mississippian Marshall Sandstone, and Early Pennsylvanian Parma Sandstone, Saginaw Formation, and Eaton Sandstone demonstrate variability in compositional maturity and source types, suggesting that Mississippian and Pennsylvanian units were likely derived from separate sources. Further distinctions are seen within the trends of the Pennsylvanian units, implying variation in eastern interior sediment dispersal in the Early Pennsylvanian. These fluctuations in provenance may be a result of differential exhumation from a single source area or migration of an axial river and subsequent drainage of different source areas as a result of Alleghanian orogenesis.
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