Formation and evolution of flood basalt magmas – combining geochemical data with the magnetic stratigraphy of the Deccan large igneous province

溢流玄武岩浆的形成和演化——将地球化学数据与德干大型火成岩省的磁性地层学相结合

• 批准号: 425902419
• 负责人: Professor Dr. Karsten Matthias Haase
• 金额: --
• 依托单位: GeoZentrum Nordbayern
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/425902419?language=en
• 关键词: Formation; evolution; flood; basalt; magmas

The eruption of the Deccan flood basalts represents one of the youngest catastrophic volcanic events on Earth and the potential environmental impact of the Deccan eruptions is debated. Little modern geochemical work has been carried out on the about 4 km thick Main Deccan Volcanic Province and thus no comprehensive geochemical data sets exist for most of the lava units. The paleomagnetic work mainly by French scientists from Paris have established the lava stratigraphy and temporal evolution of the Main Deccan flood basalts. We have obtained 158 rock samples from paleomagnetic drill cores that we want to study geochemically to produce a data set for ten lava formations representing about 3.8 km of the Main Deccan Volcanic Province including major and trace element as well as Sr-Nd-Hf-Pb isotope compositions. Based on this data set we intend to define melting processes and magma sources of the different lava units to define the input of the Réunion mantle plume, the asthenosphere, the subcontinental lithospheric mantle and the continental crust. The new data will provide important insight into mantle melting, crystal fractionation, and assimilation processes during formation of this flood basalt province.

德干洪水玄武岩的爆发是地球上最年轻的灾难性火山事件之一，德干火山爆发的潜在环境影响存在争议。在大约4公里厚的主要德干火山区进行了很少的现代地球化学工作，因此大多数熔岩单位没有全面的地球化学数据集。主要由来自巴黎的法国科学家进行的古地磁工作已经建立了主德干洪水玄武岩的熔岩地层学和时间演化。我们已经获得了158个岩石样品的古地磁钻孔岩心，我们要研究地球化学产生的数据集，代表约3.8公里的主要德干火山省，包括主要和微量元素，以及Sr-Nd-Hf-Pb同位素组成的10个熔岩地层。基于这一数据集，我们打算定义不同熔岩单元的熔融过程和岩浆来源，以定义留尼汪地幔柱、软流圈、次大陆岩石圈地幔和大陆地壳的输入。新的数据将提供重要的洞察地幔熔融，晶体分馏和同化过程中形成的这个洪水玄武岩省。