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商州蛇绿岩带具有完整的蛇绿岩套岩石组合;细碧岩与堆晶岩系具有过渡型洋中脊玄武岩地球化学特征。矿物学与岩石学研究证明,堆晶岩系是在总压与水压均较低条件下于封闭体系中分离结晶。用细碧岩主要元素估算的洋壳厚度为3.2km,证明商州蛇绿岩带形成于慢速扩张脊。堆晶岩系Sm—Nd等时线年龄为832Ma,结合北秦岭侵入岩带的同位素年龄,证明北秦岭在晋宁运动期间处于板块体制,并成为秦岭造山带演化历史中一个重要阶段。
The Shangzhou ophiolite belt has a complete ophiolite suite of rock assemblages; the spirerite and hematite series have transitional mid-oceanic ridge basalt geochemical characteristics. Mineralogical and petrological studies have shown that the heliotrope system separates and crystallizes in a closed system under conditions of low total pressure and water pressure. The estimated thickness of the oceanic crust with the main elements of the small bikite is 3.2 km, which indicates that the Shangzhou ophiolite zone formed on the slow expanding ridge. The Sm-Nd isochron age of the Jurassic system is 832Ma. Combined with the isotopic ages of intrusive rocks in the North Qinling Mountains, it is proved that the North Qinling is in plate-type during the Jinning movement and has become an important stage in the evolution history of the Qinling orogenic belt.