High-Pressure Melting of Subducted Oceanic Crust: Characterizing the Major- and Trace-Element Signatures of Slab Melts Using a Modified Diamond-Aggregate Technique

该项目的目标是：(1)建立一个25和30 kbar的实验数据库，描述岛弧下俯冲、水化洋中脊玄武岩（MORB）近固体熔融产生的蒸汽不饱和液体的主要元素组成；(2)确定含水近固相平衡与榴辉岩残留物在低熔体部分是否相互连接，这对于了解这些液体能否从板块中提取到上覆地幔楔体中具有重要意义；(3)确定斜辉石、石榴石和近固相熔体之间高场强（HFS）和稀土元素（REE）的分配。这里提出的实验将扩大模拟近固体板块熔体的地球化学特征的能力，并了解这种特征如何改变地幔并在会聚边缘喷发的熔岩中表现出来。

9706254 Stolper The goals of this project are (1) to develop an experimental data base at 25 and 30 kbar characterizing the major element compositions of vapor-undersaturated liquids produced by near-solidus melting of subducted, hydrated mid-ocean ridge basalt (MORB) beneath island arcs; (2) to determine whether hydrous near-solidus in equilibrium with an eclogite residue are interconnected at low melt fractions, which is important for understanding whether these liquids can be extracted from the slab into the overlying mantle wedge; and (3) to determine the partitioning of high field strength (HFS) and rare earth elements (REE) between clinopyroxene, garnet, and near-solidus melts. The experiments proposed here will expand the ability to model the geochemical signature of near-solidus slab melts and hoe this signature would alter the mantle and be expressed in erupted lavas from convergent margins.