Application of Well Logging Information to Secondary Porosity Analysis
ZHANG Zhen-cheng1 SUN Jian-meng1 SHI Zhen-fei 1,2 CAI Xiao-ming2 SU Yuan-da1 LIAO Dong-liang 1 1(University of Petroleum, Dongying Shandong 257061)2(Jiangsu Oilfield, SINOPEC, Yangzhou Jiangsu 225265)
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.