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Title: High P‐T Sound Velocities of Amphiboles: Implications for Low‐Velocity Anomalies in Metasomatized Upper Mantle
Abstract Metasomatized mantle xenoliths containing hydrous minerals, such as amphiboles, serpentine, and phlogopite, likely represent the potential mineralogical compositions of the metasomatized upper mantle, where low seismic velocities are commonly observed. This study presents the first experimentally determined single‐crystal elasticity model of an Fe‐free near Ca, Mg‐endmember amphibole tremolite at high pressure and/or temperature conditions (maximum pressure 7.3(1) GPa, maximum temperature 700 K) using Brillouin spectroscopy. We found that sound velocities of amphiboles strongly depend on the Fe content. We then calculated the sound velocities of 441 hydrous‐mineral‐bearing mantle xenoliths collected around the globe, and quantitatively evaluated the roles that amphiboles, phlogopite and serpentine played in producing the low velocity anomalies in the metasomatized upper mantle.  more » « less
Award ID(s):
2243184
PAR ID:
10511793
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
wiley
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
51
Issue:
5
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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