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通过对采自西藏南部喜马拉雅地块珠穆朗玛峰北坡地区奥陶系—古近系沉积地层中的2920件古地磁定向样品进行了系统测试研究,结果表明,喜马拉雅地块在显生宙时期向北漂移过程中曾发生过多次顺时针旋转运动。在奥陶纪—晚白垩世喜马拉雅地块在向北漂移过程中发生了大约20.0°的顺时针旋转运动。但在晚泥盆世末到早石炭世初曾发生了0.4°逆时针旋转,在石炭纪和早三叠世分别逆时针旋转了6.0°和8.0°,可能与晚泥盆世末到早石炭世初、石炭纪和早三叠世大陆裂谷的张裂作用有关。在晚三叠世-早侏罗世和晚侏罗世-早白垩世期间,分别发生了古纬度为2.0°和3.8°的向南回返的逆时针旋转,可能与雅鲁藏布新特提斯洋弧后扩张及洋盆开启有关。在始新世到上新世,喜马拉雅地块在相对快速北移的同时产生了约28.0°的顺时针旋转。根据古纬度数据推算,始新世以来的喜马拉雅陆-陆碰撞造山运动导致印度板块-喜马拉雅褶冲构造带-拉萨地块之间的地壳构造缩短量至少为1 000km。通过对珠穆朗玛峰地区显生宙古地磁的系统研究,为进一步深入研究冈瓦纳大陆的演化、古特提斯洋的形成、消亡历史和青藏高原隆升机制提供了科学依据。
By systematically testing 2920 geomagnetic orientation samples from the Ordovician-Paleogene sedimentary strata collected from the northern slopes of Mount Everest in the Himalayas, southern Tibet, the results show that the Himalayan massif moved northward during the Phanerozoic There have been many clockwise movements during the drift. A clockwise rotation of about 20.0 ° occurred during the Ordovician-Late Cretaceous Himalayan massif drifting northward. However, at the beginning of Early Carboniferous, a counter-clockwise rotation of 0.4 ° occurred between Late Devonian and Early Carboniferous, and rotated 6.0 ° and 8.0 ° counter-clockwise respectively in the Carboniferous and Early Triassic, possibly with the late Carboniferous to Early Carboniferous The beginning of the Carboniferous and Early Triassic continental rifts of the role of the crack. During the Late Triassic-Early Jurassic and Late Jurassic-Early Cretaceous, anticlockwise rotation of southward returns with ancient latitudes of 2.0 ° and 3.8 ° respectively occurred, which may be related to the Brahmaputra Sri Lanka after the ocean arc expansion and opening on the ocean. From Eocene to Pliocene, the Himalayan massif produced a clockwise rotation of about 28.0 ° while moving relatively fast northward. According to paleo-latitude data, the Himalayan continental-continental collision orogeny since the Eocene resulted in a crustal shortening of at least 1 000 km between the Indian Plate-Himalayan fold-thrust belt-Lhasa block. The systematic study of Phanerozoic paleomagnetic in the area of Everest provides a scientific basis for further study of the evolution of the Gondwanaland, the formation and disappearance of the Gêttesian ocean and the uplift mechanism of the Qinghai-Tibet Plateau.