Compressive deformation during the Penokean orogeny reactivated the GLTZ, which followed deposition of the Marquette Range Supergroup sediments and resulted in a north-side up motion along steep brittle-ductile faults in the eastern, low-grade portion of the Marquette Trough In the western portion of the Marquette syncline, a second episode of GLTZ reactivation took place during the uplift of the post-Huronian 2, 400-to 2, 100-million-year-old granitic Southern Complex.
