Collaborative Research: Geochemical and Geochronological Studies of Alkalic Complexes of the Deccan and Parana Basalts

9317214 Basu本合作项目将对在印度德干和巴西巴拉那两大洪水玄武岩省发现的碱性火成岩进行岩石学、Nd、Sr、pb同位素、主要元素和微量元素地球化学研究、3He/4He同位素和40Ar/39Ar年代学研究。本研究将建立碱性岩石与大洪水玄武岩火山活动主脉冲的时间关系。这项研究还将试图建立留尼旺和特里斯滕达库尼亚地幔柱的早期时间历史，它们通常被认为分别是德干和巴拉那火山活动的原因。He, Nd， Sr和Pb同位素数据的采集有望对羽流源岩浆进行表征。本研究的结果也有望有助于解决目前关于羽流冲击假说与羽流孵化假说的争论，以及岩石圈地幔在洪水玄武岩形成中的相对贡献问题。

9317214 Basu This collaborative project is to conduct petrologic, Nd, Sr, Pb-isotopic, major and trace element geochemical studies, 3He/4He isotopic and 40Ar/39Ar geochronologic studies of alkalic igneous rocks, which are found in association with the major flood basalt provinces of Deccan in India and Parana in Brazil. This research will establish the time- relationship of the alkalic rocks with respect to the main pulse of voluminous flood basalt volcanism. This research will also attempt to establish early temporal histories of the Reunion and Tristen da Cunha mantle plumes, which are generally believed to be responsible for Deccan and Parana volcanism, respectively. The proposed acquisition of the isotopic data of He, Nd, Sr and Pb are expected to characterize the plume source-magma. The results of this study are also expected to contribute to current controversies regarding plume-impact versus plume-incubation hypotheses and on questions of the relative contributions of lithospheric mantle in flood basalt generation.