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本文对产于桐柏北部二朗坪蛇绿岩片中加里东期桃园岩体和燕山期梁湾岩体花岗岩进行了系统的主量元素、微量元素和Ｓｒ－ Ｎｄ－ Ｐｂ 同位素地球化学研究。研究表明，桃园花岗岩与二朗坪基性岩具有相同的岩浆来源，两者均来自于亏损地幔源区，其中桃园花岗岩浆来自于基性岩浆的分异结晶，是与蛇绿岩共生的岩浆侵入单元，形成于与洋壳消减作用有关的弧后盆地环境，从而支持了二朗坪蛇绿岩属弧后盆地型蛇绿岩的认识。梁湾花岗岩的岩浆物质来自于南部（南秦岭）陆壳物质的部分熔融，指示在桐柏北部（北秦岭）的深部地壳中含有南秦岭陆壳物质，从而进一步证明了早期南秦岭陆壳向北俯冲叠置于北秦岭块体之下的认识。
In this paper, the main elements, trace elements and Sr-Nd-Pb isotope geochemistry of the Caledonian Taoyuan granite and the Liangshan granodiorite in the Ylangshan period have been systematically studied in the Erlangping ophiolite tablet in the north of Tongbai. The study shows that the Taoyuan granites have the same magma source as the Erlangping basic rock, both of which originate from the depleted mantle source. The Taoyuan granite magma comes from the differentiation crystallization of the basic magma and is a magmatic symbiosis with ophiolite The intrusive unit formed in the backarc basin environment related to oceanic depletion, supporting the understanding that the Erlangping ophiolite is a backarc basin type ophiolite. The magmatic material of the Liangwan granite came from the partial melting of continental crust material in the southern part of the South Qinling Mountains, indicating that the deep crust in the north of Tongbai (North Qinling) contains the South Qinling continental crust material, further demonstrating the continental crust North subduction superimposed in the North Qinling block under the understanding.