Laurentia's Grenville Loop: Tracking Rodinia Across the Mesoproterozoic to Neoproterozoic Boundary
Explore new perspectives on Laurentia's Grenville Loop and its role in tracking Rodinia across the Mesoproterozoic to Neoproterozoic boundary in this 29-minute conference talk by Yiming Zhang from the University of California, Berkeley. Delve into the paleogeography of Laurentia during the Neoproterozoic, crucial for reconstructing global paleogeography due to its central position in the supercontinent Rodinia. Examine the development of a new paleomagnetic pole from the early Neoproterozoic Jacobsville Formation, now dated to approximately 990 Ma. Learn about high-resolution thermal demagnetization experiments that resolve detrital remanent magnetization and the intraclast conglomerate test that confirms the primary nature of the magnetization. Discover how the inclination-corrected mean pole paleomagnetic position for the Jacobsville Formation supports continued plate motion of Laurentia across the equator in the late Mesoproterozoic to early Neoproterozoic. Investigate the implications of Laurentia's slowed motion following the onset of the Grenvillian orogeny and the need to revise the ages of Grenville poles. Gain insights into quantitative estimates of cooling rates and magnetic remanence acquisition timing for the Adirondack Highlands of the Grenville Province using inverted cooling history models based on new apatite U-Pb ID-TIMS thermochronological data. Read more