关于敦化盆地下白垩统的讨论

A DISCUSSION ON THE LOWER CRETACEOUS IN THE DUNHUA BASIN

前人根据敦化盆地的地层的地层,认为该盆地下白垩统为河流—湖泊相碎屑岩。通过对新钻的敦参1井岩屑录井资料的分析、对16条二维地震资料的层位标定与追踪,以及对敦化盆地早白垩世盆地演化阶段的分析,得到了以下主要结论:1)敦化盆地下白垩统可能有两种分布形态,在盆地的主体部位,以浅变质岩形态存在,而在其他部位则以正常沉积岩形态零星存在;2)敦化盆地白垩系的分布规模不大,夹持于一个北北东向的狭窄长槽内;3)敦化盆地早白垩世处于裂谷盆地发展的初始张裂阶段;4)敦化盆地下白垩统不宜作为勘探目的层。

Previous researchers interpreted the Lower Cretaceous in the Dunhua Basin as detrital rock of fluvial or lacustrine facies based on outcrop observations. In this paper, by analyzing drillcore cutttings in the DunCan1 core, seismic data from sixteen 2D seismic cross-sections,and basin evolutionary stages, we came to the following conclusions： 1） the Lower Cretaceous in the Dunhua Basin exists in two types： epimetamorphic rocks in the main part of the basin and sedimentary rocks in other parts of the basin. 2） the scale of this Early Cretaceous basin is limited in a NNE narrow trough. 3） In the Early Cretaceous period,this basin was at the early rifting stage. 4） the Lower Cretaceous can not be targeted as a potential source rock.