敦化盆地北部凹陷新生界地震资料岩性解释及地质意义

敦化盆地北部凹陷古近系珲春组和新近系土门子组共识别出6 个三级层序。通过多道地震统计法提取子波，制作敦参1 井合成记录，完成了层位标定。通过层序地层格架内基于模型的井约束反演得出高分辨率反演数据体，刻画出目的层砂地比和泥岩厚度平面展布特征。砂地比等值线图显示SH1 --ST2 沉积时期物源主要来自凹陷东南侧。在整个新生界沉积时期，主要物源供给方向变化不大，但供给强度逐渐加强。在各层序单元中，砂地比低值区、泥岩厚度高值区、地层厚度高值区与构造沉降高值区基本重合，表明断裂对沉积具有较强的控制作用。泥岩厚度高值区为泥岩的主要发育区域，由于该区主体为半深湖--深湖沉积，因此初步预测该区为烃源岩发育的有利区域。

Cenozoic lithologic interpretation of seismic data and geological significance of the northern depression of Dunhua Basin

Six third-order sequences in Paleogene Hunchun Formation and Neogene Tumenzi Formation in the northern depression of Dunhua Basin have been identified． By extracting the wavelets through multi-channel seismic statistical method and making synthetic seismic record of DC1 well，the authors completed the horizon calibration． Using the high-resolution inversion data volumes got from model-based well constraint in sequence stratigraphic framework，the authors depicted the plane distribution characteristics of sand content and sand thickness of the target layer． The contour maps of sand content showed that the provenance was mainly from the southeast of the sag during the deposition of the SH1 － ST2 ． Throughout the Cenozoic sedimentary period，the supply directions of provenance did not change much，but the intensity gradually strengthened． The low-value areas of sand content，the high-value areas of the mudstone thickness，the high-value areas of the stratigraphic thickness and the high-value areas of tectonic subsidence were coincident in each sequence unit，indicating that the fractures had strong controlon the deposition． The high-value areas of mudstone thickness were the main developmental areas for the mudstone， where were mainly semi-deep lake-deep lake deposits，thus，it can be preliminary predicted that these areas would be the most potential areas of hydrocarbon source rocks．