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在卫星遥感图像的详细地质解译分析基础上,结合野外地质与地貌观察,对帕米尔东北缘山前与印度-亚欧大陆碰撞相关的活动断层进行了分析.研究结果指出,NW-NWW走向的断层主要表现为南倾逆冲断层,并伴随有强烈的右旋走滑分量.流经活动断层带的水系显示出右旋累积位错:小水系的水平位错量为4.0～20.0 m,大河流的水平位错量达8～12 km.沿断层带的上新世至早更新世地层也显示出一致的水平位错,位错量为8～12 km.这些证据表明,帕米尔东南山前的NW—NWW走向的断层很可能开始于上新世末期至早更新世早期(2.2～Ma).研究结果首次厘定了帕米尔东北缘山前与向北逆冲州伴随的右旋走滑速率在第四纪期间达4.0～6.8 mm/a.根据与现代地震活动相关的活断层分析,推测帕米尔东北缘山前7级以上地震重复周期为1 000 a左右.
Based on the detailed interpretation of the satellite remote sensing images and the observation of the geology and geomorphology in the field, the active faults associated with the collision between India and the Eurasian continent in the northeastern Pamir were analyzed. The results show that NW-NWW strike Is mainly characterized by a south-trending thrust fault accompanied by a strong right-lateral strike-slip component.The dextral accumulated dislocations in the water system flowing through the active fault zone show that the horizontal dislocation of the small water system is 4.0-20.0 m, The horizontal dislocation of the large rivers reaches 8 ~ 12 km, and the Pliocene to Early Pleistocene strata along the fault zone also show consistent horizontal dislocations with dislocations ranging from 8 to 12 km. These evidences indicate that southeast Pamir The fault NW-NWW strike in the piedmont is likely to begin from the end of the Pliocene to early Early Pleistocene (2.2 Ma). The results of the study first determined the right-lateral strike along the northeastern Pamir and the northward thrust The slip rate reached 4.0-6.8 mm / a during the Quaternary period.According to the analysis of active faults related to modern seismic activity, it is speculated that the earthquake repetition period above the Piedmont Piedmont Level 7 above the Piedmont is about 1 000 a.