【摘要】 以珠江口盆地区域二维地震资料、钻井资料为基础,结合南海扩张演化历史,重点研究了盆地内部重要不整合面、盆地演化以及对珠江沉积体系演化的控制作用,旨在为南海北部珠江沉积体系深水油气勘探提供支持和参考。研究结果表明:珠江口盆地除基底外,发育三个重要的不整合面,即破裂不整合、陆坡跃迁不整合和陆坡坡度突变不整合;据此将珠江口盆地珠江沉积体系演化划分为四个阶段:裂陷期主要发育河流、湖泊相沉积;断陷陆坡期主要发育陆架边缘三角洲沉积(前积层较陡);拗陷缓陆坡期发育陆架边缘三角洲沉积(前积层较缓);拗陷陡陆坡期主要为三角洲—海底峡谷—海底扇沉积。断陷陆坡期与拗陷缓坡期陆架边缘三角洲的勘探,应沿陆架坡折横向去勘探;而拗陷陡陆坡期三角洲—海底峡谷—海底扇,应采取纵向勘探的思路,垂直于陆架坡折方向寻找油气。更多还原

【Abstract】 Combined with the South China Sea spreading history,based on regional 2D seismic and drilling data,the paper focuses on the research of major unconformities,evolution of the Pearl River Mouth Basin and its controlling effect on the evolution of the Pearl River sedimentary system,aiming to provide support for the deep-water hydrocarbon exploration in the basin. Results show that: besides the basement,three major unconformity surfaces are recognized in the basin,i.e. breakup unconformity,slope-migrating unconformity and slope-gradient-jumped unconformity;according to the above three unconformities,the evolution of the Pearl River sedimentary system can be divided into four stages: rifting stage mainly develops depositional system of fluvial,lacustrine; fault-slope stage mainly develops shelf-margin delta( steep foreset); gentle-slope depression stage also develops shelf-margin delta( gentle foreset);steep-slope depression stage mainly develops delta-submarine canyon-submarine fan; the exploration of shelf-margin delta developed in faulted-slope stage and gentle-slope depression stage should focus along the shelf break; the exploration for delta-submarine canyon-submarine fan in steep-slope depression stage should adopt vertical exploration ideas,that is,searching for oil and gas perpendicular to the strike of the shelf break.更多还原