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乌依塔克花岗岩体分布于乌依塔克蛇绿岩套中,与其中的基性熔岩呈侵入接触关系,形成时代比蛇绿岩套(超)铁镁质岩稍晚;岩石类型为斜长花岗岩,其中斜长石属钠长石;岩石高SiO_2,低Al_2O_3,富Na_2O,贫K_2O(<1%),里特曼指数σ为0.96~1.08,是钙质的;稀土元素总量较低,并且属轻稀土元素亏损型;除Y含量较高外,其他微量元素含量均较低;I_(sr)为 0.702 588,ε_(Sr)(t)为-16.1, ε_(Nd)(t)为 4.34。这些特征均表明,乌依塔克花岗岩体属大洋斜长花岗岩,是乌依塔克蛇绿岩套的一部分。形成环境与塞浦路斯的特罗多斯相似,为“俯冲带上”洋脊环境。
The Uytak granite bodies are distributed in the Uytahk ophiolite suite and intruded into contact with the basic lavas, forming a little later than the ophiolite mantle (ultra) mafic rocks. The rock type is inclined Long granite, of which plagioclase is albite; rocks with high SiO_2, low Al_2O_3, rich Na_2O and poor K_2O (<1%), the Rittman’s index σ is 0.96 ~ 1.08, which is calcareous; The total amount of elements is lower and belongs to the LREE depletion type. The contents of other trace elements except for Y are higher, with I sr of 0.702 588 and ε Sr of -16. 1, ε_ (Nd) (t) is 4.34. All of these features indicate that the Uytak granite belongs to oceanic plagioclase granite and is part of the Uytahk ophiolite suite. The formation of an environment similar to that of Troodos, Cyprus, “subducting” the ridge environment.