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

点击翻译按钮获取中文摘要

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.