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

9706254 Stolper本项目的目标是(1)建立一个25和30kbar的实验数据库，以表征岛弧下俯冲的、水化的大洋中脊玄武岩(MORB)近固相线熔融产生的蒸气不饱和液体的主要元素组成；(2)确定在低熔体分数时，含水的近固相线是否与榴辉岩残留物相互关联，这对于了解这些液体能否从板岩中提取到上覆地幔楔中具有重要意义；(3)确定高场强(HFS)和稀土元素(REE)在单斜辉石、石榴石和近固溶体之间的分配。这里提出的实验将扩展模拟近固相线板岩熔体的地球化学特征的能力，并发现这种特征将改变地幔，并在汇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.