地质学报2016，Vol.90Issue(4)：785-800,16.
下扬子 PTB 界线深水相区粘土岩的火山成因研究及其对 LPME 的指示意义
Volcanic Origin of Claystone near the Permian-Triassic Boundary in the Deep water Environment of the Lower Yangtze Region and Its Implications for LPME
摘要
Abstract
The volcanogenic claystone,deposited globally,especially around the Tethyan Realm in the Permian-Triassic Boundary (PTB ), plays a significant role in understanding the triggering mechanism and associated geological events for the Latest Permian Mass Extinction (LPME).Here,we present research of claystones around the PTB on mineralogy,petrology and geochemistry,which has filled the blank in this area.The results show that the components of the PTB claystone are composed mainly of volcanogenic clays (illite,etc.),and phenocryst minerals (such as quartz,calcite,pyrite and magmatic zircon).Their geochemical compositions are characterized with high K2 O and low Na2 O,relative enrichment in Large-ion Lithophile Element (LILE)and depletion in the High Field Strength Element (HFSE).All the features of the PTB claystone mentioned above suggest that the claystones are volcanogenic kalibentonite with protolith being intermediate-felsic rhyodacite and source background of arc-type magmatism.Compared with other PTB claystones found in other areas in South China,it can be inferred that all the PTB claystones have similar genesis and likely derived from felsic magmas eruption triggered by either continental collisions around paleo-Tethys Ocean or subduction of Panthalassic Ocean along eastern margin of the Pangea Continent including South China plate,and characterized by multiple episodes.These intense volcanic activities in a global scale including the volcanism associated with extensive distributions of the PTB claystones may act as key causes responsible for the Latest Permian Mass Extinction.关键词
二叠-三叠纪界线(PTB)/粘土岩/生物大灭绝/火山成因/皖南/下扬子Key words
Permian-Triassic Boundary/claystone/mass extinction/volcanogenic/southern Anhui Province/Lower Yangtze region引用本文复制引用
廖志伟,胡文蠧,王小林,曹剑,姚素平,万野..下扬子 PTB 界线深水相区粘土岩的火山成因研究及其对 LPME 的指示意义[J].地质学报,2016,90(4):785-800,16.基金项目
本文为国家重点自然科学基金项目（编号41230312）资助的成果。 （）
