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.

Deccan洪水盆地的爆发代表了地球上最年轻的灾难性火山事件之一，而Deccan爆发的潜在环境影响也引起了辩论。在约4公里厚的德干火山省，几乎没有现代地球化学工作进行，因此大多数熔岩单元都没有全面的地球化学数据集。巴黎法国科学家主要由法国科学家建立了熔岩层造影和主要的德干洪水盆地临时演变。我们已经从古磁钻芯中获得了158个岩石样品，我们希望在地球化学上研究，以生成十个熔岩地层的数据集，代表约3.8 km的Deccan火山省，包括主要和痕量元素，以及SR-ND-HF-PB同位素组成。基于此数据集，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réunion地幔羽流的输入，流动性磷圈，次陆岩石层岩石层和大陆地壳的输入。新数据将为地幔熔化，晶体分馏和同化过程提供重要的见解，在该洪水盆地省形成期间。