测井资料评价次生孔隙的方法、原理及实例

结合高邮凹陷地区实际地质情况,在地质、地震及岩芯分析的基础上,对次生孔隙的成因机制从测井角度进行了分析讨论。主要从以下几方面研究1)利用整个井段的声波测井资料可以识别成岩阶段,划分次生孔隙发育的起始层段;2)分析利用声波孔隙度与密度、中子孔隙度差值求取次生孔隙度的适用条件和范围,依条件的不同进行方法的选取;3)利用声波-电阻率幅度差法量化烃源岩中有机质含量,分析有机质经过热解后产生的有机酸对砂体产生的溶蚀作用,判断由此导致的次生孔隙发育请况;4)利用声波时差辨识异常高压层段,分析次生孔隙的发育和保存。以上方法经过实例验证,效果明显。

Application of Well Logging Information to Secondary Porosity Analysis

Based on analysis of geological, seismic and experimental analysis in Gaoyou depression, the article analyses the original mechanism of secondary porosity. The result indicates that the analysis of secondary porosity with well logging is available. The methods include: 1) the original stage of secondary porosity can be distinguished by sonic data; 2) The secondary porosity can be collected by density porosity and neutron porosity subtracting sonic porosity. The article analyses the qualification of the method; 3) The decomposition of organic matter may bring organic acid that can produce a lot of secondary porosity. The organic matter in source rocks can be measured by sonic and resistivity data; 4) the abnormal high pressure can be obtained by sonic data from which the formation and preservation of secondary porosity are analyzed. Tha above methods are tested in Gaoyou depression.