岩电参数影响因素研究

Study on Influencing Factors of Lithological-Electrical Parameters

复杂的地层条件使得岩电参数值与理论值有显著差异。通过大量岩电实验数据,研究了渗透率、孔隙度、润湿性、地层水矿化度及孔隙结构对岩电参数的影响,认为阿尔奇公式中的a值反映了岩石中泥质成份的附加导电性,泥质含量越高,a值越小;m值是对岩石中孔隙迂曲度的度量,迂曲度越高,m值越大;b值可反映岩石的润湿性,n值反映了岩石的润湿性和孔隙结构特征,其值随地层水矿化度的增加明显增大。这些认识对准确理解与应用岩电参数提供了一定的依据。

The complexity of formation condition causes obvious difference between actual value and theoretical value in lithological-electrical parameters of the formation.Based on large number of experimental data of lithological-electrical experiments,influences of permeability,porosity, wettability,salinity of formation water and porous structure on the lithological-electrical parameters are analyzed,then obtained are following understands. Parameter 'a' in Archie formula reflects the additional electric conductivity produced by clay in rock,the higher the content of clay is,the smaller the value of 'a' will be.Parameter 'm' is a measurement of tortuous degree of the pore structure,the higher the tortuous degree,the bigger the value of 'm'.Parameter 'b' can partly represents the wettability of rock.Parameter 'n' reflects the wettability and microcosmic pore structure,its value increases obviously with increase of salinity of formation water.All of these can be helpful in correctly understanding and applying lithological-electrical parameters.