早中侏罗世大鄂尔多斯古地理重建与内陆拗陷的发育演化

Paleogeography Reconstruction of the Early-Middle Jurassic Large Ordos Basin and Development and Evolution of Continental Downwarping

通过沉积构成、古流体系和相带分布等沉积的成因联系及沉积学比较分析，论证了现今鄂尔多斯与其以东山西宁武、大同等地下中侏罗统同期地层原始沉积充填的统一性，证实了它们属于同一个大鄂尔多斯沉积盆地。并按照四个时期重建和阐明了早中侏罗世盆地沉积古地理，从而揭示了大鄂尔多斯拗陷—隆升—再拗陷的形成演化的构造阶段性及其充填动力学背景的迁移性。关于内陆拗陷构造背景的探讨。

Based on the genetic relation between sedimentary architecture,paleo-drainage systems and facies distribution,and the comparative sedimentology analysis,the paper discussed the uniformity existing in the primary sediment fillings in the Lower-Middle Jurassic developed of the present Ordos basin and in Ningwu and Datong to the east of the basin.The uniformity confirmed that the strata were deposited in the same Large Ordos basin.The Early-Middle Jurassic paleogeography reconstruction,in terms of four deposition stages,revealed the tectonic stages of downwarping-uplifting-redownwarping and the migration of dynamic setting during the formation and evolution of the basin.The study on the tectonic setting for continental downwarping could determine the transformation of Indosinian-Yanshanian tectonics and the time of tectonic transformation in North China on a smaller scale.