TY - RPRT TI - Application of 2-D travel-time inversion of seismic refraction data to the mid-continent rift beneath Lake Superior AU - William J. Lutter AU - Anne M. Trehu AU - Robert L. Nowack PY - 2012 DO - 10.1029/93gl00171 UR - https://pubs.usgs.gov/publication/70186950 ID - 70186950 ER -