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塔里木盆地新疆喀什以西部分是西南天山和帕米尔两大对冲构造系统的会聚带,关于两者变形前缘和分界的确切位置存在不同认识。在乌恰县以南的玛依卡克盆地南缘,清晰可见属于帕米尔构造带、向N或NNE逆冲的帕米尔前缘逆冲推覆体(PFT)。最近野外调查在盆地北部发现了西南天山前缘的最新变形带:向南逆冲的乌拉根背斜南翼断层。断层总体近EW走向,在克孜勒苏河南岸和别尔托阔依河两岸河流阶地上形成了长约12km、坡向南的逆断坎,近地表断层产状为6°∠15°。由于乌拉根背斜及其南翼断层的活动,断层上盘阶地面上形成了多条弯滑断层,并发生了明显的反向掀斜。高阶地形成以来(区域对比表明,该阶地与木什背斜北翼T2大致为同一期阶地,其光释光年龄约为16ka),西南天山南缘吸收的总缩短量约71.4km,平均缩短速率约4.5mm/a。
The west part of Kashgar in the Tarim Basin is a convergence zone of the two major heliostracal tectonic systems in the southwestern Tianshan and Pamir. There are different understandings about the exact location of the deformation front and boundary of the two. On the southern margin of the Mayikkar basin south of Uqac County, it is clear that the Pamir thrust nappe (PFT) belonging to the Pamir tectonic belt thrusts towards N or NNE. Recent fieldwork found the latest deformation zone of the southwest Tianshan front in the northern part of the basin: the southern wing of the Wulagen anticline thrusting southward. The faults generally run in the direction of near EW, forming a 12 km long reversal ridge with a length of 12 km and a south slope on the south bank of Kyzylsu river and Beiluokuoyi river. The fault shape near the surface is 6 ° ∠15 °. Due to the activities of the Wulagen anticline and its south wing faults, multiple slip-slip faults are formed on the upper plateau of the fault and obvious overturning occurs. Since the high-level terrains were formed (regional comparison shows that the terraces are about the same light-emitting age at about the same period of T2 as the T2 of the Mushishian anticline), the total shortening of the south edge of the southwest Tianshan Mountains is about 71.4km, which is shortened on average Rate of about 4.5mm / a.