大别造山带核部天堂寨和九资河花岗岩的成岩模拟

选用大离子亲石元素 Rb、Sr对大别造山带核部天堂寨和九资河花岗岩进行成岩模拟 ,结果表明 :( 1)天堂寨花岗岩主要与非平衡熔融有关 ,偏基性片麻岩可能是天堂寨花岗岩的主要原岩 ;( 2 )九资河花岗岩主要由片麻岩的平衡非实比批式熔融作用形成 ,但也不排除由偏基性片麻岩发生非平衡熔融形成九资河花岗岩的可能性 ;( 3 )天堂寨与九资河花岗岩熔融方式的差异可能反映了大别造山带燕山晚期不同地壳层次变质岩熔融方式的差别 ,即中下地壳以高温非平衡部分熔融为主 ,而中地壳以低温平衡熔融为主 ,并伴随有局部偏基性片麻岩的非平衡熔融

PETROGENETIC SIMULATION OF TIANTANGZHAI AND JIUZIHE GRANITES IN THE CORE OF DABIE OROGENIC BELT

The petrogenetic models of Tiantangzhai and Jiuzihe granites in the core of dabie orogenic belt are simulated by the large ion lithophile elements Rb and Sr.It is suggested that:(1)Tiantangzhai granite was mainly related to disequilibrium melting,more mafic gneisses could be the main source rocks of Tiantangzhai granite;(2)Jiuzihe granite was mainly formed by equilibrium melting of gneisses;(3)the differences of melting models between Tiantangzhai and Jiuzihe granites could reflect the difference in melting models between different crustal levels of Dabie orogenic belt in late Yanshanian epoch:disequilibrium melting of high temperature occurred in the middle lower crust,equilibrium melting of lower temperature occurred in the middle crust and there might be disequilibrium melting of more mafic gneisses in local districts.