Predrill prediction of formation pressure using seismic data in deep-water area of Baiyun Depression,northern South China Sea
Guo Zhifeng1, Liu Zhen1, Lv Rui1, Liu Guochang1, Zhang Gongcheng2, Shen Huailei2
1. State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum(Beijing),Beijing 102249,China;
2. CNOOC Research Institute,Beijing 100027,China
Abstract：Deepwater area of northern South China Sea is featured by sparse well controls,shallow depth of drilling and difficulty of getting precise formation velocity.Considering the unique conditions in this area,this paper first improves models for pressure computation and extracts formation velocity,then discusses how to build precise computation models and how to obtain high-quality seismic absolute velocity,finally presents a method on predrill prediction of formation pressure using seismic data.A tendency prediction model for formation pressure has been improved through compressibility factor,a low frequency velocity model has been set up,and a relative velocity has been extracted by means of color inversion.Then seismic absolute velocity is acquired by compounding these two velocities.Ultimately,with the new calculation model and high-quality seismic absolute velocity,predrill prediction of formation pressure has been conducted at Baiyun depression.Testified by measured pressure,the predicted results turn out to be with high-precision.Our study shows that hydrostatic pressure develops in Zhuhai Formation and Zhujiang Formation,high amplitude overpressure develops in Paleogene at Baiyun Depression.Overpressure system would provide strong power for hydrocarbon upward migration.
郭志峰, 刘震, 吕睿, 刘国昌, 张功成, 沈怀磊. 南海北部深水区白云凹陷钻前地层压力地震预测方法[J]. 石油地球物理勘探, 2012, 47(1): 126-132.
Guo Zhifeng, Liu Zhen, Lv Rui, Liu Guochang, Zhang Gongcheng, Shen Huailei. Predrill prediction of formation pressure using seismic data in deep-water area of Baiyun Depression,northern South China Sea. OGP, 2012, 47(1): 126-132.
