南海北部珠江口盆地深水区碳酸盐岩发育特征及地震识别

由于南海的多次扩张、拉伸、消减运动，在珠江口盆地白云深水区发生了陆架裂陷和海水入侵等地质现象，形成了海相碳酸盐岩生长发育的基础地质条件。对珠江口盆地深水区碳酸盐岩的发育地质背景、地质特征、发育规律、地震响应特征以及深水区灰岩发育的主控因素进行了探讨，结果表明白云深水区主要发育两种类型的碳酸盐台地；古隆起镶边台地以及火山建隆孤立台地。台地沉积主要发育在古隆起周缘、构造高部位、火山隆起周缘，并被钻井所证实。在白云深水区东沙隆起西南缘、云荔低凸起、荔湾凹陷北缘、荔湾凹陷南缘及顺鹤隆起发育典型的生物礁，钻井证实有珊瑚、红藻、苔藓虫等造礁生物。生物礁地震特征具有强的连续反射顶、底界面，丘状反射外形，内部结构或空白、或杂乱，具有前积、加积、退积等层序结构。

Development characteristics and seismic identification of carbonate rocks in the deep-water area of the Pearl River Mouth Basin,northern South China Sea

Due to multiple spreading and subduction of the South China Sea, some geological phenomena may be observed in the Baiyun deep water area of the Pearl River Mouth Basin, such as multiple continental shelf rifting and sea water intrusion. After integrated analysis, the geological characteristics, development pattern, seismic response characteristics and main controlling factors affecting carbonate sedimentation in the deep water area of the Pearl River Mouth Basin are discussed in this paper. Drilling results confirm that platforms commonly developed in the periphery of paleo-uplift, structure high and volcanic uplift margin, thus there are two types of platforms in the Baiyun deep water area, the rimmed platforms on paleo uplifts and the isolated platforms on volcanic highs. Hermatypic organism like corals, red algae and bryozoans have been found in some typical reefs on the southwestern margin of the Dongsha uplift, Yunli low uplift, the northern margin of Liwan sag, and the southern margin of Liwan sag and Shunhe uplift. The reefs have clear seismic reflection characteristics, for example strong and continuous top and bottom, domal seismic reflection, blank or disordered inner reflection structure and progradational and aggradational as well as retrogradational reflection sequences.