By duplex repulsive boundary element modulo is supplied to the underground resistivity

摘要

PROBLEM TO BE SOLVED: To develop practical procedures, methods applied to an underground investigation, by measuring a potential to be measures at a potential electrode corresponding to a current supplied to a current electrode at each measuring point on a measuring line, transforming a driving term to a boundary integration and obtaining a specific resistance distribution from the potential to be measured. ;SOLUTION: An apparent specific resistance is calculated from a feed current and a measured potential obtained after topographic features are corrected. When a measuring line is too long, an analysis measuring line is divided to several sub measuring lines. An average value of the apparent specific resistances is calculated for every sub measuring line. If a ground face is flat or only an underground electrode is measured, a general solution of a potential is obtained analytically from the average value of specific resistances. A difference of the measured potential and the general solution is calculated together with the measured potential and a boundary condition, and a parameter is determined. A distribution of driving terms in an analysis area is calculated. A specific resistance distribution of each point is calculated for all current sources included in the sub measuring lines according to the method of least squares. The specific resistance distributions of sub areas are connected, thereby obtaining a final analysis result.;COPYRIGHT: (C)1999,JPO