辽河断陷大民屯凹陷静北灰岩古潜山地层时代研究

AGE OF THE JINGBEI LIMESTONE ANCIENT BURIED HILL IN THE DAMINTUN DEPRESSION OF THE LIAOHE FAULTED DEPRESSION

辽河断陷大民屯凹陷静北灰岩古潜山的地层时代,在上世纪80年代初期被认为属于中元古代长城纪。运用生物地层学、岩石学、地球物理测井、地震地层学、古地磁学及微量元素分析等多重地层划分对比研究方法,对该灰岩古潜山地层时代进行了综合分析,证实静北灰岩古潜山的地层由中元古界蓟县系、下古生界寒武系至奥陶系和上古生界石炭系至二叠系3套地层构成,这一新认识改变了将该灰岩古潜山地层时代整体归属中元古代长城纪大红峪组和高于庄组的传统认识。

Since early 1970s, the age of the Jingbei limestone (ancient buried hill, Damintun depression, Liaohe rift) has been considered to belong to the Mesoproterozoic Changchengian. This paper undertakes a comprehensive study on the age of the limestone using biostratigraphy, petrology, geophysical logging, seismic stratigraphy, paleogeomagnetism and trace element analysis and proves that the Jingbei limestone consists of the Mesoproterozoic Jixianian, Cambrian to Ordovician of the Early Paleozoic, Carboniferous to Permian of the Late Paleozoic. The new understanding modified the traditional knowledge that the limestone belongs to the Mesoproterozoic Dahongyu and Gaoyuzhuang Formations.