塔里木盆地库车地区早第三纪伸展盆地的证据

库车坳陷早第三纪伸展构造的证据有三，一是盆地在早第三纪时虽然沉陷范围较大，但沉陷速率较低。其沉降速率与处于伸展构造环境的侏罗、白垩纪盆地相似，而与处于挤压构造环境的三叠纪前陆盆地和晚第三纪前陆盆地相去甚远；二是在盆地东部吐格尔明背斜的北冀与南面塔北隆起的下第三系砾岩中发育有高角度的同生正断层；三是在盆地下第三系地层中发现的灰质砾岩、含砾灰岩等海相沉积和海相腹足类化石及膏盐层均运离古南天山造山带分布，剖面上也不具有前陆盆地沉积典型的楔状沉积的特征，由此不仅说明本区早第三纪海侵的存在，而且还说明在早第三纪发生过伸展作用。

Evidence for Paleogene Extensive Kuqa Basin, Tarim

There are three lines of evidence for the extenive tectonic environment of Kuqa basin during Paleogene time. Like the Jurassic and Cretaceous extensive basin, the Paleogene basin has very low subsiding velocity although the subsiding area is very large. Some growth normal faults which indicate an extensive tectonic environment were found in the north limb of Tugerming anticline, eastern Kuqa basin. Furthermore, the gastropoda fossils as well as some index sediments such as calcirudite and limestone of marine facies environment were also found in the basin. Furthermore, the distribution of these sediments shows typical features of an extensive basin and differs clearly from a foreland basin.