RECEIVER FUNCTION ANALYSIS OF THE MICHIGAN BASIN

The Michigan Basin is a circular intracratonic basin with a diameter of about 400 km (Howell and van der Pluijm, 1999). It is thickest in the present-day Saginaw Bay region and lies above the eastern arm of the Midcontinent Rift, that stretches westward into Minnesota and south towards Kansas. Receiver function study on the western arm finds a continuous subcrustal transition layer that tracks gravity highs. The estimated depth of the base of sedimentary cover also correlates to gravity anomaly trends (Zhang et al., 2016). This project focuses on new seismological constraints of the crustal structure beneath Michigan using P-to-s receiver functions calculated from the recordings of distant (> 4,000 km) earthquakes at USArray seismometers in Michigan. We measure variations of the thickness of the crust and sediments within and outside the Michigan Basin with the goal to place the Michigan Basin in a broader geologic and tectonic context.