关于蓟县型中、上元古界沉积环境及内蒙地轴的性质

On the Jixian-type mid-upper Proterozoic sedimentaryenvironment and the character of Inner Mongolian Axis

内蒙地轴和燕辽坳陷都是华北地台北缘的二级大地构造单元。本文在对蓟县型中、上元古界沉积环境和对内蒙地轴演化历史的初步研究基础上 ,认为蓟县型中、上元古界沉积盆地于长城—蓟县期 ,在北部与广海相连 ,属于陆表海发展阶段 ;在青白口期 ,由于北部逐渐抬升 ,该沉积盆地才具有陆内盆地性质。内蒙地轴在长城—蓟县期总体处于水下环境 ,青白口期才开始抬升为古陆 。

Research on the sedimentary environment of the Jixian?type mid?upper Proterozoic in the North China shows that many problems need to be further studied. We consider that the Jixian?type mid?upper Proterozoic was not formed in the intracontinental aulacogen, but it formed in marginal basin of the northern margin of the ancient North China platform. The Inner Mongolian Earth Axis (IMEA) is not a tectonic unit uplifted for a long time. IMEA was under the sea level from Changcheng age to Jixian age, and it began to uplift and became an ancient land after Qingbaikou age, belonging to the marginal upwarping zone of northern margin of the North China platform. The large?scale lifting occurred in Mesozoic or the later.