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松潘地块位于青藏高原的东缘,处于中国大陆东西向构造与南北向构造的结合部位,特殊的构造环境使其长期控制并影响着中国大陆的形成与演化。探测松潘地块的岩石圈细结构,揭示其与东昆仑-西秦岭造山带的关系,既可为研究青藏高原东北缘板块碰撞的深部过程奠定基础,同时又关联着松潘地块的油气远景评价。2004年完成了第一条横过松潘地块北缘若尔盖盆地和西秦岭造山带的长约257km的深地震反射剖面,首次揭露出若尔盖盆地和西秦岭造山带岩石圈的细结构,发现若尔盖盆地和西秦岭造山带同属统一的稳定的大陆地块,并且下地壳均以北倾的强反射为主要特征。这种北倾的反射为松潘地块向西秦岭下地壳俯冲提供了地震学证据。近于平坦的Moho反射特征反映出西秦岭造山带在造山后又经历了强烈的伸展作用。
Located on the eastern margin of the Qinghai-Tibet Plateau, the Songpan Plot is located at the junction of East-West and North-South structures in mainland China. Its special tectonic setting has long-term implications for the formation and evolution of the Chinese mainland. Detecting the fine structure of the lithosphere in the Songpan block and revealing its relationship with the East Kunlun-West Qinling orogenic belt can not only lay a foundation for studying the deep process of the plate collision in the northeastern margin of the Qinghai-Tibet Plateau, but also relate to the long-term evaluation of the Songpan block . In 2004, the first deep seismic reflection profile of about 257 km long across the northern margin of Songpan block and the Western Qinling orogenic belt was completed. For the first time, the fine structure of the lithosphere in the Zoige and West Qinling orogenic belts was revealed. And the West Qinling orogenic belt belong to a unified and stable continental massif, and the lower crust is characterized by the strong reflection of the north dip. This north-dipping reflection provides seismological evidence for the subduction of the Lower Western Qinling Songpan block. The near-flat Moho reflectivity reflects that the West Qinling orogenic belt experienced strong stretching after orogenic.