高压物理学报2025，Vol.39Issue(10)：11-22,12.DOI:10.11858/gywlxb.20251026
水镁石的弹性波速及其对俯冲带水含量的意义
Elastic Wave Velocity of Brucite and Its Implications for Water Cycling in Subduction Zones
摘要
Abstract
Brucite,a key constituent mineral in hydrated peridotites within subduction zones,can occupy up to the volume fraction of 15%of these water-saturated rocks.Investigating the high-pressure elastic wave velocities of brucite is thus crucial for understanding the composition,seismic velocity structure,and deep-water cycling processes of hydrated peridotites in subduction zones.In this study,dense polycrystalline brucite was synthesized from Mg(OH)2 reagent under 4 GPa and 523 K for 2 h.The elastic wave velocities and moduli of brucite were measured up to 14 GPa using ultrasonic interferometry.The results demonstrate that the elastic wave velocities and moduli of brucite increase with increasing pressure.By integrating seismic tomography with mineral assemblage modeling,we constrained the water content in the low-velocity anomaly regions of the mantle wedge using the Voigt-Reuss-Hill(VRH)model.Our estimations indicate that the water mass fraction ranges from 3.0%-10.0%in low-velocity anomaly zones of the mantle wedge above the subducting slab at depths of 20-40 km,and 1.0%-3.0%within the subducting slab at depths of 60-80 km beneath northeastern Japan.关键词
水镁石/波速/俯冲带/水含量/高压Key words
brucite/wave velocity/subduction zones/water content/high pressure分类
数理科学引用本文复制引用
张瑞,王多君,蔡闹..水镁石的弹性波速及其对俯冲带水含量的意义[J].高压物理学报,2025,39(10):11-22,12.基金项目
国家自然科学基金(91958216,42430206,42374211,42474132) （91958216,42430206,42374211,42474132）
中央高校基本科研业务费专项资金 （）
