珠江口盆地东沙隆起早中新世台缘带特征及勘探方向  

Geological Feature and Prospecting Potential of Early Miocene Platform Margin Belt in Dongsha Uplift, Zhujiangkou Basin

作　　者：曾清波 张功成 廖宗宝 印斌浩 王升兰 纪沫 

机构地区：[1]中海油研究总院

出　　处：《海相油气地质》2015年第1期17-24,共8页Marine Origin Petroleum Geology

基　　金：国家科技重大专项"南海深水区大中型油气田成藏主控因素与有利勘探方向"(编号:2011ZX05025-006)资助

摘　　要：基于钻井、地震资料的系统分析,珠江口盆地东沙隆起早中新世大型碳酸盐岩台缘带沿L7井、H6井及F1井一带呈环带状分布。根据斜坡结构与沉积充填特征的差异,台缘带可划分为四个区段,不同区段具有不同的油气成藏条件。东南段,位于白云凹陷与东沙隆起的过渡带,斜坡横向宽度大、地势陡,礁滩发育,由于下伏地层缺乏有效输导砂体沟通烃源,该段存在一定勘探风险;中南段,斜坡类型转换为断坡,斜坡宽度、高差相对减小,台缘礁滩发育,位于构造脊附近的礁滩体为下一步勘探的有利目标;西段,斜坡宽度小、坡度缓,礁的规模相对减小,生物碎屑滩较发育,应以构造-岩性复合圈闭为突破目标;北段,斜坡规模小,且为背风带,礁滩相对不发育,与惠州凹陷邻接部位的小规模生物碎屑滩发育带具有一定的勘探潜力。Based on analysis of drilled and .seismic data, the large early Miocene carbonate platform margin is distributed along a cyclical area from Well L7 to Well H6 and to Well F1 in Dongsha Uplift, Zhujiangkou Basin. On account of slope geometry and sedimentary filling characteristics, the platform margin can be divided into four zones, i.e. the southeast, the center-south, the west and north zones, each of which displays their own different condition of hydrocarbon accumulation. The slope is wide and steep and reef-shoals widely develop in the southeast zone where oil exploration will face some risk due to lack of effective sandbodies to conduct with the underlying strata although it is near hydrocarbon-rich Baiyun Sag. The slope is not so wide and steep but reef-shoals also widely develop in the center-south zone where the reef-shoals near ridges maybe are the favorable exploration targets. The slope is gentle but not wide and bioclast shoals develop in the west zone where the structural-lithologic traps that are distributed along structure ridges should be the breakthrough targets as the center-south zone. In the north zone, the slope gets small and reef-shoals do not develop because of locating in leeward so that the small-scaled bioclast shoals adjacent to Huizhou Sag maybe is of exploration potential.

关 键 词：珠江口盆地 东沙隆起 中新世 构造特征 生物礁 生物碎屑滩 勘探潜力 

分 类 号：TE121.2[石油与天然气工程—油气勘探]