Testing Evolution Models for Garnet Peridotite in the Mantle and Crust during Orogenic Cycles

Columbia University, New York NY

Investigators

Abstract

0000937 Langmuir The presence in many orogens of presumably mantle-derived garnet peridotite in high-grade crustal material has remained difficult to understand, as continental crust was thought to be too buoyant to be subducted into the mantle, and correspondingly, mantle peridotite too dense to be intruded upward into continental crust. This project will utilize two occurrences of garnet peridotite in continental orogenic rocks in the Caledonian Orogen of Norway. Extensive isotopic data will be employed to test several possible models for these occurrences. Results should help explain the common but apparently anomalous occurrence of those rocks not only in the Norway examples, but in other similar orogens.