The recovery of the Middle-Late Triassic prototype basin in the western Tuha basin-eastern Junggar Basin

Abstract

Based on the data of mud logging, well logging and seismic data, the erosion thickness and original sedimentary thickness of the Middle-Late Triassic prototype basin in the west of Turpan-Hami Basin-Zhundong area were restored and analyzed. The erosion thickness of the Middle-Upper Triassic was calculated by the seismic stratigraphic thickness trend method, and the prototype basin was analyzed by combining the original sedimentary thickness. The results show that the erosion thickness in the west of Turpan-Hami Basin is 0m-600 m, which decreases first and then increases from north to south and then decreases. The erosion thickness of the Middle-Upper Triassic strata in the Zhundong area is 0m-400m, which increases first and then decreases from south to north. The maximum original thickness of the Middle-Upper Triassic strata in the western Tuha Basin is 1400 m in the front of the Bogda Mountain, which is thickened from north to south. The original thickness of the Middle-Upper Triassic strata in the eastern Junggar Basin generally increases from north to south. Bogda Mountain and its adjacent areas show a quasi-plainization process of cutting high and filling low. The scope of Taibei depression and Tainan depression further expanded, the sedimentary center moved southward, the Pubei low uplift became the denudation area, and the Keyayi depression and the Toksun depression developed. Beisantai uplift and Shaqi uplift in the north of Zhundong area are developed and their scope is expanding, and Zhundong depression area is developed in the south.