盆地超压地层识别方法——以四川盆地通南巴构造带为例  

The technology for detection of overpressured zones in formations:an example from the tongnanba fold-belt, sichuan basin, China

作　　者：薛冈[1] 管路平[1] 王良书[1] 杨子兴 孙成龙 

机构地区：[1]南京大学地球科学系,南京210093 [2]中石化南京石油物探研究所,南京210014

出　　处：《地球物理学进展》2004年第3期645-651,共7页Progress in Geophysics

摘　　要：　在四川盆地通南巴构造带,首先以井芯、录井资料和钻井泥浆比重资料为约束条件,利用泥岩段声波测井资料建立区域"正常压实趋势线";然后用精细速度处理获得的地震层速度剖面减去区域"正常压实趋势线"建立速度差值剖面,速度差值剖面上的异常低速带定性指示了地层超压范围;再采用速度 压力变换技术,建立压力系数剖面,定量分析地层超压,地层压力计算结果与实际钻井采用的泥浆比重较好吻合,说明利用地球物理资料、钻井资料及地质资料不但可以定性识别超压地层,而且可以定量预测地层压力;对不同压力封存箱的认识有助于分析地层含油气性延展方向,指导下一步勘探部署.In the TongNaBa fold belt, Sichuan basin, a regional normal compaction trend, the relationship between velocity and depth or travel time, is built from shale sonic log data. The regional normal compaction trend is corrected by core , lithology logging and mud weight. In time domain, velocity difference section, the difference between the normal compaction velocity and the observed seismic interval velocity, can detect the area of overpressured formations qualitatively. In depth domain, the sections of geopressure and pressure ratio are calculated, so the overpressured formations can be identified quantitatively. The geopressure from calculation accords with mud weight in practice preferably. The field case study shows that the geophysical data together with lithology information and geological background can predict geopressure reliability, and analysis of each pressure compartment can help to find the extent of oil and gas, then aid to further exploration.

关 键 词：地球物理数据 正常压实趋势线 速度差值剖面 压力系数剖面 超压地层 预测地层压力 

分 类 号：P631[天文地球—地质矿产勘探] TE1[天文地球—地质学]