Study on Geological Characteristics of Porphyroclasic Lava Rock in Xiangshan, Jiangxi
DAI Jia-qi;WANG Chao;Fundamental Science on Radioactive Geology and Exploration Technology Laboratory,East China Institute of Technology;
E Hu ridge porphyroclastic lava of the group Originated from depression type volcanic basin in Xiang Shan, for a set of hypabyssal, ultra shallow into, eruption facies volcanic rocks. In this paper, on the basis of predecessors' research results, summarizing the petrology and geochemical characteristics of Xiangshan crushed lava, to discuss the rock geochemical characteristics and genetic types and tectonic environment. Porphyroclastic lava is a overall performance of aluminium, high potassium calc-alkaline rhyolitic volcanic rock series, Enrichment of high field strength element Th、U、Zr、Hf and large ion lithophile elements such as: Rb、K、La、Ce、Nd、Sm, The apparent loss of the elements such as: Ti、Nb、Sr、P、Ba and medium-sized Eu negative anomaly, rare earth element content is higher, light rare earth relative enrichment of heavy rare earth elements is obvious. Xiangshan porphyroclastic lava mainly comes from the earth's crust, formation process may have a mantle source material, its formation environment and marina process related to the subduction of the Pacific plate to Eurasian plate structure related back-arc extensional extend, orogenic period after the intraplate orogenic belt is the product of magmatic activity.
【CateGory Index】： P588.1;P619.14