孔隙结构对电阻率影响机理研究

STUDIES ON THE INFLUENCING MECHANISMS OF PORE STRUCTURES ON RESISTIVITIES

储层孔隙结构对电性的影响主要通过孔隙结构指数（m）传递。在其他条件相同、孔隙度为12．5％的条件下，当m从2．0降至1．7时，储层电阻率下降43％；当m为1．44时，储层电阻率下降值高达67．5％。压汞法实验资料分析表明，m值受岩石孔隙结构影响，中值半径减小时对应的m值减小；岩石填隙物含量越高，越容易在孔吼中形成微细毛管发育的优良导电网络，导致储层岩石整体电阻率下降。当孔隙度与含水饱和度相同时，储层电阻率随m值的减小而减小。

The influences of the pore structures on the electric properties are mainly transited by the index of the pore structures （m）. The reservoir resistivity is thought to by dropped 43% when m reduced from 2.0 to 1.7 under the conditions of 12.5% porosity and the same other terms; when m is 1.44, the dropped value is up to 67.5%. The experimental data analyses of mercury injecting method show that the value m is impacted by the pore structures of the rocks, when the radium of the medium value decreased, the corresponding value m is also reduced; the more the interstitial matter is, the easier the better electricify-conducting network with well-developed micro-fine capillaries can be formed in pores and throats, thus the reduced overall resistivity of the reservoir rocks will be caused. When the porosity is as same as the water saturation, the reservoir resistivities will be dropped with the decrease of the value m.