冀东柳赞油田古近系沙河街组层序地层及岩相古地理?

柳赞油田位于河北省滦南县与唐海县交界处,是冀东油田的主力油田之一。构造上处于燕山褶皱带前缘，渤海湾盆地南堡凹陷的东部。受柏各庄断层活动及古斜坡地形的影响，该区古近系沙三段地层属于近源快速堆积沉积，分选差，成熟度低，岩相复杂，为典型的扇三角洲沉积。通过对沉积特征和沉积相带展布的分析，建立了工区扇三角洲的沉积模式。以层序地层学原理和方法为手段，应用测井和三维地震资料，通过不整合面、湖泛面等层序界面和沉积旋回的识别，将柳赞油田沙河街组地层划分为4个准层序组，12个准层序，建立了高分辨率的层序地层格架，分析了准层序在垂向上的叠置样式，把准层序组归纳为进积式和退积式两种类型，确定了优质储层在准层序和准层序组中出现的位置及分布规律。论文在分析沙河街组沉积时期古地形、古气候与古生态特征的基础上，应用砂岩厚度等值线图，恢复了柳赞油田古近系沙河街组岩相古地理面貌。研究表明，工区内发育扇三角洲前缘亚相，分支水道是主要的砂体微相，砂体沿北东－南西向延伸，与古物源方向基本一致。

SEQUENCE STRATIGRAPHY AND LITHOFACIES PALAEOGEOGRAPHY OF THE SHAHEJIE FORMATION OF PALEOGENE IN LIUZAN OILFIELD,EASTERN HEBEI PROVINCE

The Liuzan Oilfield at boundary between the Luannan County and Tanghai County of Hebei Province is located at the frontal zone of the Yanshan fold belt and eastern Nanpu Sag of Bohaiwan Basin,and is one of the most important oil fields of Jidong Oilfield.The stratigraphy of Member 3 of Shahejie Formation of Paleogene influenced by the Baigezhuang Fault and inclined palaeotopography shows the characteristics of low sorting, low maturity and complicated lithofacies,and belongs to fan delta deposition.With method of sequence stratigraphy, sequence boundaries(unconformity surface and lake flooding surface) and sedimentary cycle of Member 3 of Shahejie Formation in Liuzan Oilfield are recognized with seismic and logging data, and high resolution sequence frame is established, i.e., 4 parasequence sets and 12 parasequences. The paper analyzes parasequences' superposition style, divides parasequence sets into progradational sequence and retrograding sequence and determines the location of high-guality reservoirs in parasequences and parasequence sets. Based on the analyses of palaeotopography, palaeoclimate, palaeoecology and sedimentary facies analysis, lithofacies palaeogeography of Member 3 of Shahejie Formation in Liuzan Oilfield is reconstructed with thickness isoline map of sandstone. For Member 3 of Shahejie Formation in Liuzan Oilfield, the depositional environment is fan delta front and the distributary channel is the main sandstone microfacies. Sandstone is distributed along NE-SW direction,which is identical with that of palaeoprovenance.