A “Top Down” and “Bottom Up” Perspective of Crust Formation using Igneous and Detrital Zircon

Basement rocks of the southwestern United States are thought to represent one of the grandest loci of continental crust formation in Earth history. However, debates over the tectonic setting of crust formation have been ongoing in the literature for over 30 years. My approach has been to combine U-Pb geochronology with Hf-isotope analysis of both igneous and detrital zircon from the oldest rocks in the southwestern U.S. By comparing the isotopic signature of plutonic zircon formed from deeply-derived molten rock to detrital zircon initially deposited at the surface before their burial into the middle continental crust, My colleagues and I attempt to understand the formation of continental crust from a “bottom-up” and “top-down” perspective. This approach has produced a powerfully informative dataset that is leading to a paradigm change in the community’s understanding of the tectonic history of the southwestern U.S.laurentia summaryPublications:

  1. Holland et al., 2015
  2. Holland et al., 2018

Full-text downloads are available at Mark E. Holland’s ResearchGate profile