Syntectonic microstructural evolution is a well‐known phenomenon in the mantle and lower crust associated with two main processes: grain size reduction through dynamic recrystallization and development of crystallographic preferred orientation (CPO). However, the effects of annealing via static recrystallization on grain size and CPO have been largely overlooked. We investigated mantle annealing by analyzing a suite of kimberlite‐hosted garnet peridotite xenoliths from the Wyoming Craton. We focus on five xenoliths that show microstructures reflecting different degrees of recrystallization, with annealed grains characterized by distinctive faceted boundaries crosscutting surrounding, nonfaceted matrix grains. These textures are indicative of discontinuous static recrystallization (DiSRX). Electron backscatter diffraction analysis further demonstrates a ∼10°–20° misorientation between DiSRXed grains and the matrix grains, resulting in an overall weaker CPO. These characteristics are remarkably similar to microstructures observed in samples that were annealed after deformation in the laboratory. Measurements of the thermal conditions and water contents associated with the last equilibration of the xenoliths suggests that high homologous temperatures (
This content will become publicly available on December 1, 2024
- Award ID(s):
- 1757371
- NSF-PAR ID:
- 10468714
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Acta Materialia
- Volume:
- 261
- Issue:
- C
- ISSN:
- 1359-6454
- Page Range / eLocation ID:
- 119395
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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