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根据龙门山前陆盆地西缘沉降中心、冲积扇侧向迁移、活动构造地貌和古地磁等标志及龙门山在中生代以来的走滑作用和走滑方向的标定研究,结果表明:龙门山断裂带具有走滑性质,走滑方向曾发生过反转,在反转之前以左行走滑作用为特征,在反转之后以右行走滑作用为特征。根据地层记录和古地磁证据,认为龙门山走滑方向反转的时间应介于43 M a~3.6 M a之间,即由中生代至早新生代时期的左行走滑作用反转为晚新生代时期的右行走滑作用。然对龙门山断裂带走滑方向反转的成因初步分析认为晚新生代龙门山右行走滑作用是印-亚碰撞后构造作用的产物,晚三叠世至早新生代左行走滑作用是青藏高原自晚三叠世以来大陆碰撞作用导致松潘-甘孜褶皱带北东-南西向缩短的产物。
Based on the sedimentation centers of the western margin of the Longmenshan foreland basin, the lateral migration of alluvial fans, the tectono-geology and paleomagnetism of the Longmen Mountains and the calibration of the strike-slip and strike-slip directions of the Longmenshan since Mesozoic, the results show that the Longmenshan fault zone With the nature of strike-slip, the direction of strike-slip has been reversed and characterized by left-slip before reversal and right-slip after reversal. Based on the stratigraphic records and paleomagnetic evidence, it is considered that the reversal time of Longmen Shan strike slip should be between 43Ma and 3.6Ma, that is, the left-lateral strike slip in the Mesozoic to Early Cenozoic periods is reversed to Late Cenozoic The right time of the slide function. However, a preliminary analysis of the genesis of the strike-slip direction reversal of the Longmenshan fault zone suggests that the right-lateral strike slip of the Late Menomono in the Late Cenozoic was the product of tectonic effect after the Indian-Asian collision. The left-lateral slip in Late Triassic to Early Cenozoic is the result of the Qinghai-Tibet The continental collision since the Late Triassic in the plateau led to the NE-NW shrinkage of the Songpan-Ganzi fold belt.