青藏东昆仑晚古生代末—中生代中酸性火成岩与陆内造山过程

利用岩石大地构造学的研究方法回溯了东昆仑晚古生代末—中生代构造岩浆演化历史。研究表明，东昆仑晚海西期—早燕山期构造演化分为３个阶段：（１）洋脊形成与扩张阶段（３０９～２６０Ｍａ）；（２）大洋板块大规模俯冲阶段（２６０～２３０Ｍａ），火成岩具安第斯型活动大陆边缘构造属性；（３）陆内造山阶段（２３０～１９０Ｍａ），陆壳的厚度相当于２６０～２３０Ｍａ期间的两倍，南、北边缘构造性质与深部过程具较明显差异与不对称性。南缘深部总体特征是“壳热而幔冷”，暗示着陆壳与壳下岩石圈之间可能沿莫霍面有较大的构造拆离；北缘在壳底具岩浆底侵作用，其深部特征为“壳冷幔热”。自晚海西期—早燕山期东昆仑岩石圈缩短总量（平均值）约为１４６３ｋｍ。

LATE PALAEOZOIC MESOZOIC INTRACONTINENTAL OROGENIC PROCESS AND INTERMEDATE ACIDIC IGNEOUS ROCKS FROM THE EASTERN KUNLUN MOUNTAINS OF NORTHWESTERN CHINA

The magmatic and tectonic evolution process of the eastern Kunlun mountains, northwestern China from Late Palaeozoic to Mesozoic era is studied. This process could be divided into three stages: (1) formation and spreading of ocean ridge(309～260Ma). In this stage, ocean crust of Late Palaeozoic Mesozoic era began formating and had ocean floor spreading. Ophilite of the southwestern Kunlun mountains was formed; (2) subduction stage of ocean plate of the eastern Kunlun mountains(260～230Ma). Petrotectonic assemblage in this stages is intermediate acidic CA and HKCA igneous rocks formed in the active continental margin; and (3) stage of intracontinental orogenic process(230～190Ma). The paired igneous which are both muscovite granite and the shoshonite series volcanic rock zones are regarded as one of the most important signature to identify the spatial range of the intracontinental orogenic belt. The paired igneous rock zones show that continental crust have been thickened during T 3 to J 1.