Title :
Scale model experiments to study low-frequency electromagnetic resolution of multiple conductors
Author :
Gupta, O.P. ; Kakirde, S.T. ; Negi, Janardan G.
Author_Institution :
Nat. Geophys. Res. Inst., Hyderabad, India
fDate :
3/1/1988 12:00:00 AM
Abstract :
Low-frequency analog modeling experiments were conducted to investigate the response of two vertical half-planes to the horizontal loop electromagnetic method. Both insulating and conducting environments are considered. Several characteristic profiles of in-phase and quadrature components caused by diffracting objects were obtained. The results include the following: (1) the response of closely spaced conducting scatterers can be discriminated only if their separation S⩾ the transmitter-receiver separation L; (2) the distance W between the two extreme zero crossovers of in-phase and quadrature components; (3) the quadrature profiles are more sensitive than in-phase curves in resolving the target conductors; (4) for S<0.5 L, much higher estimates of conductance and lower estimates of the depth than actual situations will be obtained if the data is interpreted with the conventional half-space phasor diagrams
Keywords :
geophysical prospecting; geophysical techniques; terrestrial electricity; EM induction; EM prospecting; analog modeling experiments; closely spaced conducting scatterers; diffracting objects; geoelectric; horizontal loop electromagnetic method; in phase component; low-frequency electromagnetic resolution; multiple conductors; phasor diagrams; quadrature components; response; scale model experiment; technique; terrestrial electricity; transmitter-receiver separation; two vertical half-planes; Conductors; Earth; Electromagnetic diffraction; Electromagnetic fields; Electromagnetic modeling; Electromagnetic propagation; Electromagnetic scattering; Geophysics; Insulation; Physics;
Journal_Title :
Geoscience and Remote Sensing, IEEE Transactions on