论文部分内容阅读
通过对桐柏北部（相当于北秦岭构造块体）燕山期老湾岩体和梁湾岩体花岗岩主元素、微量元素和Ｐｂ－Ｓｒ－Ｎｄ同位素地球化学的研究，分析了岩浆的物质来源，并用来指示地壳深部组成。结果表明，老湾和梁湾花岗岩均属壳源型花岗岩，岩浆物质并不来自于北秦岭基底和华北克拉通南缘基底，而是来自南秦岭构造块体中桐柏杂岩的部分熔融。这表明在桐柏北部的深部地壳中，含有南秦岭的地壳物质，从而进一步证明了早期南秦岭陆壳向北俯冲并叠置于北秦岭块体之下的认识。
By studying the major elements, trace elements and Pb-Sr-Nd isotope geochemistry of the Laowan granite and the Liangwan granite in the north of the Tongbai (corresponding to the North Qinling tectonic block), the source of magma, And used to indicate the deep crust composition. The results show that both Laowan and Liangwan granites belong to crust-derived granites. The magmatic material does not come from the basement of the North Qinling and the basement of the southern North China Craton, but from the partial melting of the Tongbai complex in the South Qinling tectonic block. This indicates that the deep crust in the northern part of Tongbai contains the crustal material of the South Qinling Mountains, further confirming the understanding that the early South Qinling continental crust was subducted northward and superimposed under the North Qinling block.