新疆地学断面(独山子-泉水沟)走廊域及邻区地球物理调查综合研究

The Integrated Geophysical Observation and Research along the Xinjiang (XUAR) Geotransect and Its Surrounding Areas

沿新疆地学断面 (独山子 泉水沟 )走廊域实施了多种地球物理方法调查研究。对岩石圈现今活动性、位场异常图像处理与岩石圈变形踪迹、地体基底构造与边界断裂划分等进行了综合研究。整条地学断面处于近SN向的挤压环境中。挤压力一方面来自印度板块向北的推挤 ,另一方面来自增厚岩石圈根带下沉的拖力。塔里木岩石圈呈刚性 ,且整体变形 ,对应力的传播起到放大的作用。阿尔金断裂向南延展进入西昆仑造山带 ,南端与泉水沟断裂相接 ,并且斜截了库地断裂和康西瓦断裂。中天山地体与北天山地体与准噶尔盆地统属同一基底构造区 ,南天山地体与北塔里木统属同一基底构造区。南北塔里木是 2个基底性质不同的地体。 4 0°N是分割南北塔里木的地体边界断裂。研究结果表明 ,新疆新构造运动不是古板块的简单复活。

The multifarious geophysical investigations and researches were carried out in 1996～2000 along the Xinjiang Geosciences transect. The lithospheric activities, deformation traces, basement structures and border faults of the terrains were studied. New achievements reveal that the whole transect is located in a South North compression environment. The force of compression comes not only from the Indian plate but also from the downgoing drag of the lithosphere root. The lithosphere of the Tarim basin shows rigid and uniform deformation, which enhances the transformation of force. Altyn Tagh fault extends southward into the West Kunlun orogenic belt. The southern end of Altyn Tagh fault connects with Quanshuigou fault, and cuts Kuda fault and Kangxiwa fault obliquely. The Central Tianshan terrane and the North Tianshan terrane have a common basement with the Jungar basin, and the basement tectonic framework of the South Tianshan terrain is the same as that of North Tarim. South Tarim and North Tarim are two different terrains in the nature of the basement, and their boundary fault is roughly along the 40°N line. The researches show that the Neo tectonic activity of Xinjiang is not the simple reactivation of an ancient plate.