珠江口盆地珠Ⅰ、珠Ⅲ坳陷裂陷期湖相分布差异及其控制因素

Different distribution of lacustrine facies and its controlling factors during rifting stage, ZhuⅠand Zhu Ⅲ Depressions, Pearl River Mouth Basin

刘志峰 王升兰 印斌浩 张洋 肖伶俐

Liu Zhifeng Wang Shenglan Yin Binhao Zhang Yang Xiao Lingli

中海油研究总院,北京100027

Research Institute of China National Offshore Oil Corporation, Beijing 100027, China

通过对珠江口盆地珠Ⅰ、珠Ⅲ坳陷裂陷期湖相分布特征的对比发现，2个坳陷内的湖相发育程度存在着明显差异性，即珠Ⅲ坳陷湖相发育程度明显小于珠Ⅰ坳陷。综合分析认为，产生该现象的主要原因是在裂陷期珠Ⅲ坳陷拉张程度小于珠Ⅰ坳陷，导致其不利于湖相发育。裂陷期坳陷的拉张程度受控于多种地质因素，包括应力方向、基岩岩性、区域断裂等。珠Ⅰ、珠Ⅲ坳陷在基底岩性、凹陷分布格局、基底大型隐伏断裂的影响、控凹断裂走向等方面存在着诸多差异，这些因素控制了坳陷拉张程度的差异性，也控制了湖相分布的差异性。

The distribution of lacustrine facies during rifting stage in the Zhu Ⅰ and Zhu Ⅲ Depressions of the Pearl River Mouth Basin shows that lacustrine facies spread much more widely in the Zhu Ⅰ Depression. It might be explained by the smaller extensional level of the Zhu Ⅲ Depression. The extensional level of a depression is affected by many factors, such as stress orientation, basement lithology and region faults. The differences of basement lithology, sag distribution, large potential fault below Cenozoic and sag-controlling fault orientation lead to the different extensional level of the Zhu Ⅰ and Zhu Ⅲ Depressions, and further control the different distribution of lacustrine facies.

国家科技重大专项课题“近海富烃凹陷资源潜力再评价和新区、新领域勘探方向”（2011ZX05023-001）资助。

https://doi.org/10.11781/sysydz201305523