东海X气田钻后M气藏地震振幅特征分析及认识

Analysis and Study on Seismic Amplitude Characteristics of M Gas Reservoir after Drilling X Gas Field of East China Sea

蔡华 刘江

CAI Hua LIU Jiang

中海石油(中国)有限公司上海分公司, 上海 200030

Shanghai Branch of CNOOC Ltd., Shanghai 200030, China

X气田位于东海南部西部凹陷带,主要分布于2200~2800m的古近系古新统明月峰组中孔中低渗的砂岩储层中。M气藏是常规气藏,也是该气田的主力气藏之一。钻后通过AVO模拟及实钻资料统计与分析,证实气区强振幅的形成与气藏分布密切相关。进一步通过正演模型,研究了气藏厚度与地震振幅的强弱变化之间的关系,以及"亮点"分布范围与实际气藏面积之间的对应关系。通过上述研究及认识,可以有效地指导该气田气藏预测及地质储量计算工作。

The X gas-field is located in the western sag in southern part of East China Sea. The main gas layers are distributed in the sandstones with medium porosity and permeability, belonging to Mingyuefeng Formation of Palaeocene and with a depth range from 2 200 m to 2 800 m. M gas reservoir is normal reservoir, and the main gas reservoir of this gas filed. It has been confirmed through post-drilling AVO modeling and statistic analysis of drilling data that high-amplitude is highly related with distribution of gas reservoir. By forward modeling, a study has been done about the relationship between gas reservoir thickness and seismic amplitude, and the corresponding relationship between the distribution range of spot area with practical gas area. Through the above study, the forecast of gas reservoir and calculation of geological reserves of the gas-field can be done effectively.

https://doi.org/10.3969/j.issn.1008-2336.2014.04.011