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对燕山造山带辽西早白垩世义县组火山岩的 Nd,Sr,Pb同位素分析 ,作者认为义县组火山岩起源于岩石圈地幔的部分熔融 ,岩浆在上侵过程中发生了结晶分异和同化混染作用 ,即 AFC过程。与新生代汉诺坝玄武岩中的中生代镁铁质麻粒岩捕虏体和太古代片麻岩对比研究 ,发现义县组火山岩与这些镁铁质麻粒岩捕虏体有许多地球化学相似之处 ,而与长英质麻粒岩捕虏体和太古代各种片麻岩差别较大。作者认为早白垩世燕山板内造山带发生了强烈的岩石圈伸展作用 ,辽西义县组火山岩和汉诺坝新生代玄武岩中的镁铁质麻粒岩捕虏体均为这一构造背景下的产物 ,它们属于幔源岩浆喷发与大规模玄武zh质岩浆底侵作用形成的“同质异相体”
Nd, Sr and Pb isotopic analyzes of the volcanic rocks of Yixian Formation of the Early Cretaceous in the western Yanshan Orogenic Belt, the authors believe that the volcanic rocks of the Yixian Formation originated from the partial melting of the lithospheric mantle and crystallized during the process of upheaval Dyeing, the AFC process. Compared with the Mesozoic mafic granulite xenoliths and Archean gneisses from the Cenozoic Hannuoba basalts, the volcanic rocks of the Yixian Formation have many geochemical similarities with these mafic granulite xenoliths , And with the British quartz granulite xenoliths and Archean various gneiss difference. The authors believe that the Early Cretaceous Yanshanian intraplate orogenic belt experienced a strong lithospheric extension. The volcanic rocks of the Yixian Formation in Liaoxi and the mafic granulite xenoliths in the Cenozoic basalts of Hannoba are all structurally They belong to the “homogeneous heterogeneous body” formed by mantle-derived magmatic eruptions and massive basaltic zh magmatic emplacement.