Testing Models of Subduction Initiation and Metamorphic Sole Formation in the Easton Metamorphic Suite, NW Cascades
Research Mentor(s)
Mulcahy, Sean
Description
Metamorphic soles are thin slivers (<500 m) of high-grade rock that record the first few million years of intra-oceanic subduction when the down-going slab is accreted to the upper plate and heated by the overlying mantle (e.g. Agard et al., 2016). Metamorphic soles preserve an inverted metamorphic gradient and form either as a coherent unit that has been subducted and cooled (Peacock, 1987), or as a sequence of units that are progressively underplated and accreted (Soret et al., 2017). Despite their importance to understanding early subduction processes, the mechanisms responsible for creating metamorphic soles remain poorly understood. This study aims to answer the question: Does the inverted metamorphic sequence of metamorphic soles form by downward heat advection or by underplating and accretion? I will test this hypothesis within the Easton Metamorphic Suite of NW Washington that preserves a metamorphic sole formed during initiation of subduction beneath the North American margin.
Document Type
Event
Start Date
15-5-2019 9:00 AM
End Date
15-5-2019 5:00 PM
Location
Carver Gym (Bellingham, Wash.)
Department
Geology
Genre/Form
student projects, posters
Subjects – Topical (LCSH)
Subduction zones--Cascade Range; Metamorphic rocks--Cascade Range
Geographic Coverage
Cascade Range
Type
Image
Rights
Copying of this document in whole or in part is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this document for commercial purposes, or for financial gain, shall not be allowed without the author’s written permission.
Language
English
Format
application/pdf
Testing Models of Subduction Initiation and Metamorphic Sole Formation in the Easton Metamorphic Suite, NW Cascades
Carver Gym (Bellingham, Wash.)
Metamorphic soles are thin slivers (<500 >m) of high-grade rock that record the first few million years of intra-oceanic subduction when the down-going slab is accreted to the upper plate and heated by the overlying mantle (e.g. Agard et al., 2016). Metamorphic soles preserve an inverted metamorphic gradient and form either as a coherent unit that has been subducted and cooled (Peacock, 1987), or as a sequence of units that are progressively underplated and accreted (Soret et al., 2017). Despite their importance to understanding early subduction processes, the mechanisms responsible for creating metamorphic soles remain poorly understood. This study aims to answer the question: Does the inverted metamorphic sequence of metamorphic soles form by downward heat advection or by underplating and accretion? I will test this hypothesis within the Easton Metamorphic Suite of NW Washington that preserves a metamorphic sole formed during initiation of subduction beneath the North American margin.