内蒙古扎兰屯地区晚古生代格根敖包组地层的发现及其地质意义

THE DISCOVERY AND GEOLOGICAL IMPLICATION OF THE LATE PALEOZOIC GEGENAOBAO FORMATION IN ZHALANTUN AREA, INNER MONGOLIA

通过区域地质调查,在内蒙古扎兰屯地区前人划分的"大石寨组"中,新发现了一套走向北东向的地层,岩石组合为安山质熔岩、中性火山碎屑岩和正常沉积碎屑岩,并含有动植物化石,为一套海陆交互相火山-碎屑岩沉积建造.本文将其厘定为格根敖包组,时代为晚石炭—早二叠世.该套地层在扎兰屯地区为首次发现,对大地构造及地层划分等基础地质的研究有着重要意义.

During the regional geological survey, the Gegenaobao Formation, which had been regarded as the Lower Permian Dashizhai Formation, was discovered in Zhalantun of Inner Mongolia. The strata are NE striking, Late Carboniferous-Early Permian in age, with rock association of andesitic lava, intermediate pyroclastics and normal clastics, containing animal and plant fossils, to be a volcanic-sedimentary rock series of paralic facies. This formation is firstly found in Zhalantun area. The discovery is importantly significant for basic geological study, such as tectonics and stratigraphic division.