PRINCIPLES OF MEASURING COAL THICKNESS BY RESISTIVITY METHOD ALONG A HORIZONTAL BOREHOLE AND ITS FORWARD SIMULATION

The methods and principles of measuring coal thickness by resistivity method along a horizontal borehole in coal sean are presented． Several sorts of geologic-electrical models are forward simulated by using linear numerical filter． Many modelling results have showed that the resistivity curves reflect obviously the variation of coal thickness， which are enabled to measure the coal seam with the thickness mors than 0.8m．