广东麒麟新生代玄武质角砾岩筒中岩石包体的研究

The Xenoliths From Qilin Cenozoic Basaltic Pipe, Guangdong

本文以广东麒麟玄武质角砾岩筒中的各种岩石包体为研究对象，通过详细的岩石学研究，按岩石类型将包体划分为四类：即橄榄岩、辉石岩、辉长岩质麻粒岩、花岗岩和火山－沉积岩，并依据包体的岩石地球化学特征，讨论了它们的成因；其中辉长岩质麻粒岩是来自本区下地壳的样品，是由上地幔部分熔融产生的熔体“底侵”于地壳底部结晶，又经变质作用的产物。同时，本文结合实测的和计算的地球物理参数，讨论了该区的岩石圈分层。

The various xenoliths from Qilin basaltic pipe, Guangdong are studied in this paper. Onthe basis of rock types and detailed petrologlcal studies, these xenoliths can be divided into four classes: peridodites, pyroxenites, gabbroic granulites, granite and volcanic-sedimentary rocks. The genesis of the xenolithsare discussed by studying of their geochemical characteristics. It is believed that the gabbroic granulites are thesamples from lower crust of this region, which were formed by crystailizasion of 'underplating' magmatic meltfrom upper mantle, and underwent metamorphism. In addition, by integrating with measured and calculatedgeophysical data, the division of the lithosphere in this area is also discussed.