海相三角洲沉积单元划分及其对勘探砂体对比的意义--基于现代珠江三角洲沉积水动力综合研究

从水文地质、地理、地貌学角度,融合河流、波浪、潮汐水动力,对现代珠江三角洲体系中河流、波浪和潮汐的成因单元共存现象进行综合解读,建议引入“沉积单元”的概念,搭积木似组合亚相和相,重建海相三角洲沉积体系。同时认为,对于前积特征明显的三角洲中进行砂体对比,层序地层学等时格架内的砂体多采用前积式(斜层)对比方案,但传统的岩性地层(平层)对比方案也有可取之处。尤其在开发阶段,进行沉积微相导向的砂体对比时,建议结合地震反射特征确定对比方案。在具体对比手段上,应结合沉积砂体展布、油气水关系、邻井对比、动态压降等实际资料,进而建立储层地质模型,使模型既能反映沉积环境,更能预测储层。

Depositional Elements Definition of Marine Delta and Significance to Sand Body Correlation in Petroleum Exploration: From hydrodynamic analysis on modern Pearl River Delta

Ignited by the existence of fluvial, wavy, tidal sediments deposited together in Pearl River mouth-Modaomen, and the land-ocean interaction theory, considering the reality of microfacies definition of delta, we introduced the hydrogeology, geography and geomorphology in to the delta-define scheme, and suggested to integrate fluvial, wavy and tidal microfacies, to re-organize the depositional elements to reconstruct marine delta. This scheme also reveals that referring to the neighbor science like hydrogeology, geography and geomorphology can be fruitful for sedmentological research, especially for petroleum exploration. Based on the field research on Modaomen, those sand bodies which distribute various styles on different orientation show that when we correlate the sand layers during petroleum exploration and development, we should consider the seismic reflection, sedimentary distribution, hydrocarbon-water relations pressure, and even the distance between wells.