Structural and Thermal Evolution of an Infant Subduction Shear Zone: Insights From Sub-Ophiolite Metamorphic Rocks Recovered From Oman Drilling Project Site BT-1B.

ABSTRACT: Subduction interface thermal structure changes drastically within the first few million years of underthrusting (i.e., subduction infancy). Metamorphic soles beneath ophiolites record snapshots of dynamic conditions and mechanical coupling during subduction infancy. Beneath the Samail Ophiolite (Oman), the sole comprises structurally higher high-temperature (HT) and lower low-temperature (LT) units. This inverted metamorphic gradient has been attributed to evolving metamorphic Pressure-Temperature (P-T) conditions during infancy; however, peak P-T and timing of LT sole subduction are poorly constrained. Oman Drilling Project core BT-1B sampled the base of the ophiolite in a location lacking the HT sole. Metasedimentary and meta-mafic samples collected from 104 m of core reveal that

SUBMITTER: Kotowski AJ 

PROVIDER: S-EPMC9285456 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature