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地质地球化学证据表明金塔南山岩带是通过转换挤压作用把性质各异、形成于不同构造环境的岩石会聚而成的变质地质体 ,其中主要组分斜长角闪岩的Sm -Nd等时年龄为 74 5±59Ma ,原岩为玄武岩 ,分属钙碱性系列和拉斑系列。稀土元素配分型式为平坦型 (拉斑系列 )到富集型 (钙碱性系列 ) ;相对N—MORB ,低Ti,富集LILE ,相对亏损HFSE ,Nb、Ta、Ti表现为明显的负异常 (钙碱性系列 )到无异常 (拉斑系列 ) ;INd(t) =0 51193,14 3 Nd/14 4 Nd =0 512 878,εNd(t)=+4 9± 0 2 ,推测斜长角闪岩应为不同程度部分熔融的岛弧岩浆作用的产物。提示本岩带是在新元古代中期华北克拉通与塔里木克拉通之间的古大洋俯冲消减的结果。
Geological and geochemical evidence shows that the Quinta Nanshan rock belt is a metamorphic geological body formed by convergent rocks formed by different tectonic environments through transformation and extrusion, in which Sm-Nd and other major components of amphibolite At the age of 74 5 ± 59Ma, the original rock is basalt, belonging to the series of calcium and alkaline and pull the spot series. Rare earth elements are of flat type (plaque series) to enriched type (calcareous series); relative N-MORB, low Ti, enriched LILE, relatively depleted HFSE, Nb, Ta and Ti show significant negative anomalies (Calc-alkaline series) to no abnormality (plaque series); INd (t) = 0 51193,14 3 Nd / 14 4 Nd = 0 512 878, εNd (t) = + 4 9 ± 0 2, Amphibolite should be the product of the partial melting of the island arc magma to varying degrees. It is suggested that this zone is the result of the palaeoclimate subduction between the North China Craton and the Tarim Craton in the mid-Neoproterozoic.