番禺低隆起三级层序的界面识别标志及沉积特征

 番禺低隆起地区是珠江口盆地最有利的油气勘探区域之一,目前已经在该区发现了多个气田和含气构造,天然气地质储量达1200亿m³,成藏条件非常有利。随着勘探的不断深入,目前面临着可供钻探的构造目标越来越少的难题。通过对珠江口盆地番禺低隆起三维地震资料解释,结合钻井、古生物、测井等资料,开展层序划分对比工作,建立区域层序地层格架,揭示了研究区三级层序界面的识别标志及等时地层结构的基本特征,并对层序格架内沉积相的构成、分布特征及演化、有利储盖组合特征进行了研究,对今后该区的油气勘探具有重要指导意义。

The Sequence Boundaries Identification and the Depositional Characteristics in the Third-order Sequence Stratigraphic Framework of Panyu Low Uplift

The Panyu low uplift is one of the most favorable oil and gas accumulation zones in the Pearl River Mouth Basin. Multiple gas fields and gas-bearing structures have been found in this area. The OGIP is estimated as about 120 billion cubic meters. How to find new oil and gas exploration areas on the basis of exploratory results is important for the sustainable development of the natural gas exploration in the Pearl River Mouth Basin. In this paper, the sequence stratigraphic framework of this area is built and the sequence structure characteristics, the depositional evolution and its control factors are analyzed based on the previous studies, the seismic data, the well log curves and the paleontology. The sequence boundary identification and the structure characteristics of the sequence stratigraphy are presented, together with the distribution and the development of sedimentary facies in the sequence stratigraphic framework of this area. It turns out that there are several different sedimentary sequence development models in the evolution stage of the Pearl River Mouth Basin. The sequence structure characteristics and the distribution of the sedimentary systems are mainly controlled by the sea level variation and the faulted slope-break zone, as a result, there are five reservoir-seal assemblages formed in this area, among which two have a good exploration potential.