中子-密度重叠识别气层法在长庆气田的应用

Application of Neutron-Density Overlapping to Identify Gas Reservoir in Changqing Gas Field

叙述了补偿中子测井和密度测井在天然气层和水层的特征,以及用中子-密度曲线重叠和中子孔隙度-密度孔隙度曲线重叠判识气层的方法。在长庆气田,用中子-密度曲线重叠法可排除干层,它在干层呈现"负异常"或"正负异常不定",且重叠面积很小;用中子孔隙度-密度孔隙度曲线重叠法来区分气层和水层,即气层呈现"正异常",而水层呈现"负异常"。得出了中子-密度曲线重叠面积与天然气产量的回归关系式。

Described are characteristics of compensated neutron log and density log in gas and water layers,and methods of neutron and density curve overlapping and neutron porosity and density porosity curve overlapping to identify gas reservoir.In Changqing Gas Field,dry layer can be debarred by neutron and density curve overlapping,it shows "negative abnormity" or "uncertain positive or negative abnormity" in dry layer,and the overlapping area is small;gas layer and water layer can be distinguished by neutron poros...