摘要
为了正确认识长期水驱油藏剩余油分布状况,以渤海湾地区高孔渗油藏的岩石物理数据为依据,结合冀东油田两个区块2次三维地震采集的资料,从可行性研究、叠前和叠后互均化处理以及动态油藏描述等方面对水驱油藏四维地震技术进行了系统研究。研究结果表明:通过叠前和叠后互均化处理可以基本消除地震采集差异造成的影响;对于长期人工水驱开采油藏,由于物性和注水压力变化可造成17%~19%的速度降低,可以直接利用互均化后的叠后地震振幅差异监测水驱前沿;对于天然能量开采油藏,只有孔隙流体性质变化,因此造成的地震波速度变化很小,利用叠后地震振幅差异无法刻划油藏的变化,必须利用叠前地震信息(如互均化处理后新老资料弹性波阻抗反演的差异)才能突出油藏的变化。
To estimate the residual oil distribution in long-term water flooding reservoirs, 4D seismic study is implemented based on the 3D legacy seismic and petrophysical data of reservoirs with high porosity and permeability in Bohai Bay, including feasibility analysis, pre-stack and post-stack cross-equalization, dynamic reservoir monitoring. Through the cross-equalization, the difference caused by the factor of acquisition is almost eliminated. For long-term artificial water flooding reservoirs, the seismic velocity decreases by 16%~18% because of the variation of reservoir properties and pressure, and post-stack seismic amplitude differences can be used to monitor the water flooding forefront directly. For natural water drive reservoirs, the only variable factor is fluid saturation which could cause subtle seismic velocity variation. In this case, the information from pre-stack seismic data should be used to highlight the reservoir variation instead of post-stack amplitude differences. For example, the differences of two pre-stack elastic impedance inversions can reflect the reservoir variation very well.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2007年第4期437-444,共8页
Petroleum Exploration and Development
关键词
四维地震
可行性
物性变化
流体变化
压力变化
互均化处理
弹性波阻抗反演
水驱油藏
4D seismic
feasibility
physical property change
fluid change
pressure change
cross-equalization processing
elastic impedance inversion
water flooding reservoir