江西寻乌破火山口火山-侵入杂岩地球化学特征及其成因意义  

The Geochemistry and Petrogenesis of the Volcanic-intrusive Rocks in Broken Crater of Xunwu, Jiangxi

作　　者：巫建华[1] 刘帅[2] 周维勋[2] 章邦桐[1] 

机构地区：[1]南京大学地球科学系,江苏南京210093 [2]东华理工学院,江西抚州344000

出　　处：《东华理工学院学报》2004年第1期33-43,共11页Journal of East China Institute of Technology

基　　金：核工业科学基金资助项目 (Y1 1 2 1 8960 4 0 1 )

摘　　要：位于武夷隆起带和南岭构造带过渡部位、受北东向会昌 -寻乌断裂带和东西向三南 -寻乌断裂带控制的寻乌破火山口 ,发育一套由碎斑熔岩和花岗斑岩组成的火山 -侵入杂岩。碎斑熔岩属高钾拉斑岩石系列 ,分异指数和SiO2 ,Rb含量较高 ;Al2 O3,CaO ,ALK ,TFeO ,MgO ,TiO2 ,REE ,Sr,Ba,Zr含量较低 ;A/NKC ,A/NK ,Al2 O3/TiO2 ,Rb/Sr ,Rb/Ba比值高 ;CaO/Na2 O ,LREE/HREE ,δEu值低 ,为后造山环境下砂屑岩或岩浆岩较低温度、较低熔融程度形成的岩浆的产物。花岗斑岩属碱性岩石系列 ,分异指数和SiO2 ,Rb含量较低 ,Al2 O3,CaO ,ALK ,TFeO ,MgO ,TiO2 ,REE ,Sr ,Ba ,Zr含量较高 ;A/NKC ,A/NK ,Al2 O3/TiO2 ,Rb/Sr,Rb/Ba比值低 ,CaO/Na2 O ,LREE/HREE ,δEu值高 ,为后造山环境下砂屑岩或岩浆岩较高温度、较高熔融程度形成的岩浆的产物。Xunwu Broken Crater locted in the transition zone of Wuyi rise belt and Nanling tectonic belt, controlled by the NE direction Huichang\|Xunwu fault belt and the EW direction Sannan-Xunwu fault belt, and developed a volcanic-intrusive rocks that made up of porphyroclastic lava and granite-porphyry. Porphyroclastic lava belongs to high potassium tholeiitic series, with higher differentiation index and the content of SiO_2, Rb, and higher ratio of Al_2O_3/(Na_2O+K_2O+CaO), Al_2O_3/(Na_2O+K_2O), Al_2O_3/TiO_2, Rb/Sr and Rb/Ba, and lower content of Al_2O_3, CaO, Na_2O+K_2O, TFeO, MgO, TiO_2, REE, Sr, Ba, Zr and lower ratio of Al_2O_3(Na_2O+K_2O+CaO),Al_2O_3/(Na_2O+K_2O),Al_2O_3/TiO_2,Rb/Sr,Rb/Ba, and lower ratio of CaO/Na_2O, lree/hree, δEu, They are likely to result from partial vrelting of sandstone or magmatite in the lower temperature and lower degree melting under the postorogenic environments. Granite-porphyry belongs to the alkaline rock series, with lower differentiation index and the content of SiO_2, Rb, and higher content of Al_2O_3, CaO, Na_2O+K_2O, TFeO, MgO, TiO_2 and higher ratrio of CaO/Na_2O, LREE/HREE, δEu . They are likely to result from partial melting of sandstone or magmatite in the higher temperature and higher degree melting under the postorogenic environments.

关 键 词：江西 寻乌 破火山口 火山-侵入杂岩 地球化学特征 形成原因 

分 类 号：P588[天文地球—岩石学]