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柴达木盆地西部的茫崖坳陷发育了第四纪湖泊冰水沉积,其特征是灰绿、黄褐色页岩和泥岩中含大量的冰水滴石。滴石最大粒径可达4cm×12cm,成分复杂,有火山岩、变质岩及沉积岩。孢粉分析表明,其形成时代为第四纪,极有可能为更新世,与我国西部的第四纪冰期形成时代相同,但具体期次尚不能确定。柴西茫崖坳陷第四纪冰水沉积证据充分,对于研究我国第四纪冰期及青藏高原的形成演化、古气候、古地理具有重要意义。另外,第四纪冰水沉积充分说明在第四纪冰期青藏高原没有被整个大冰盖所覆盖。
Quaternary sediments of icy water developed in the Mangya depression in the west of the Qaidam basin. They are characterized by a large number of ice-water dripping stones in gray-green and yellow-brown shale and mudstone. The largest diameter of drip stone up to 4cm × 12cm, composition is complicated, volcanic rocks, metamorphic rocks and sedimentary rocks. Sporopollen analysis shows that the formation age is Quaternary, most probably Pleistocene, which is the same as the formation age of Quaternary glacial period in western China, but the exact period can not be determined yet. Evidence of Quaternary glacial water deposition in the Mangya Cliff depression is sufficient for the study of the formation and evolution of Quaternary glaciations in China and the Qinghai-Tibet Plateau, paleoclimate and palaeogeography. In addition, the Quaternary ice deposition shows that the Qinghai-Tibet Plateau was not covered by the entire ice sheet during the Quaternary glacial period.