Experimental Study of Pyroxenite Partial Melting in the MORBSource Region

MORB源区辉石岩部分熔融实验研究

• 批准号: 9706526
• 负责人: Marc Hirschmann
• 金额: $ 9.26万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-02-15 至 1999-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9706526&HistoricalAwards=false
• 关键词: Experimental; Study; Pyroxenite; Partial; Melting

9706526 Hirschmann Summary: The chemical differences in mid-ocean ridge basalts at one location on a ridge and along a ridge have been noted for some time. Various models of melting, mantle heterogeneity, melt migration through the mantle have been proposed to explain these differences. The PI hypothesizes that the differences are due to the presence pyroxenite veins in the mantle that melt preferentially and at greater depth than the bulk of the mantle. Thus this small amount of material (about 5% of the mantle) could contribute more than 20% of the melt that reaches the surface in some places, thus causing the chemical differences seen in the basalts. The PI plans to melt pyroxenites under mantle conditions to determine the compositions of melts that might contribute to the ocean ridge basalts.

小行星9706526 摘要：一段时间以来，人们一直注意到大洋中脊玄武岩在脊上某一位置和沿脊沿着的化学差异。不同的熔融模型，地幔不均匀性，熔体通过地幔迁移已被提出来解释这些差异。PI假设，这些差异是由于地幔中存在辉石岩脉，这些辉石岩脉优先熔融，并且比地幔大部分深度更深。 因此，这少量的物质（约占地幔的5%）可以贡献超过20%的熔融物到达某些地方的表面，从而导致玄武岩中的化学差异。PI计划在地幔条件下熔化辉石，以确定可能有助于形成洋脊玄武岩的熔体成分。