摘要
莺歌海盆地东方5区各砂体在原始地震剖面上与周缘已钻井具备相似的地震特征,水道砂内含气或者含水均表现为明显的强振幅异常,定性分析很难判断其含气性;但将振幅增益减弱为原来的1/3后,东方5-3_A2砂体振幅强度明显强于其他目标区。从振幅本质出发,逐一梳理其振幅影响因素;并根据本区已钻井揭示的岩石物理参数建立正演模型,定量分析流体变化和厚度调谐对振幅的影响,认为东方5-3_A2砂体振幅异常应为砂体含气和厚度调谐的共同影响;另外通过该区已钻井AVO正演模拟,认为该区相同孔隙度下含气储层和含水储层AVO类型一致,但截距有明显差异,东方5-3_A2砂体截距更大,应为含气表现,是下步勘探的首选目标。
The original seismic section of Dongfang 5 zone channel sand has the similar characteristic with the nearby drilled wells. The channel sand shows the strong amplitude anomaly whether it contains water or gas. It is hard for gas-bearing prediction by the qualitative analysis. But weaken the seismic amplitude gain to 1 /3 of the original data,the Dongfang5-3_A2 sand has the stronger amplitude than the other sand. From the nature amplitude,sorts out the influence factors one by one,the forward model was build by the drilled wells rock physics parameters and analyzed the influence of the fluid and thickness change for the seismic amplitude by quantitative analysis,and it consider that the Dongfang5-3_A2 sand＇s stronger amplitude is the combined effect by the change of the fluid and thickness. And through the study of the drilled wells＇ AVO forward model it is found when the sand has the same porosity it may has the same AVO style whether it contains water or gas in the study area,but the intercept is obviously different,and the Dongfang5-3_A2 sand has the bigger intercept,it may be the gas bearing performance,so it is the best target for forward exploration.
出处
《科学技术与工程》
北大核心
2016年第1期162-167,共6页
Science Technology and Engineering
基金
国家"十一五"重点科技攻关项目(2011ZX05023-004)资助
关键词
莺歌海盆地
水道砂
振幅
厚度调谐
流体
AVO
Yinggehai basin
channel sand
amplitude
tuning thickness
fluid
AVO style
