PIRE: ExTerra Field Institute and Research Endeavor: Western Alps

ExTerra Field InstituteThe ExTerra Field Institute and Research Endeavor (E-FIRE) united US scientists studying rocks exhumed from paleo-subduction zones (through ExTerra: Exhumed Terranes) with European colleagues also working on subduction systems (through ZIPZooming In between Plates, a Marie Curie training network). E-FIRE Field Institutes gathered ExTerra and ZIP scientists in the field to trace the cycle of rocks and fluids through the subduction process as recorded in Earth’s premier example of a fossil subduction zone: the Western Alps, Europe. Eleven early-stage researchers (ESRs), including PhD students and post-doctoral fellows based at nine different U.S. institutions, collected field data and rock samples to address three overarching research questions:

  1. How do elements cycle among crust, mantle and Earth’s surface?
  2. What are the depths, temperatures, and timescales of rock transformation and fluid release within subduction zones? and
  3. What is the mechanical behavior of materials within subduction zones?

The projects adopted a variety of approaches to address these questions, including mineralogical and petrological analysis; textural characterization; geochemical analysis of major and trace elements (e.g., HFSE, REE, halogens), stable isotopes (e.g., δ7Li, δ11B, δ13C, δ18O, δ37Cl), and radiogenic isotopes (e.g., U-Th-Pb, Sm-Nd, Rb-Sr); and thermodynamic and geodynamic modeling.