
TY  - JOUR
A1  - Reid, J. E. 
A1  - Howlett, A. 
T1  - Application of the EM-31 terrain conductivity meter in highly-conductive regimes
JF  - ASEG Extended Abstracts
JO  - ASEG Extended Abstracts
Y1  - 2001
VL  - 2001
IS  - 1
SP  - 1
EP  - 4
KW  - 
UR  - https://doi.org/10.1071/ASEG2001AB117 
N2  - Over highly-conductive earths, the maximum effective depth of investigation of the EM-31 terrain conductivity meter is reduced from its theoretical value of 6 m at low induction numbers. In extreme cases, depths of investigation may be as small as ~2.5 m and ~4 m for the vertical coplanar and horizontal coplanar coil configurations respectively. Sensitivity of the instrument to the depth of the overburden-basement boundary in two-layered earth models is highly dependent on the geoelectric structure. Over highly-conductive earths, the in-phase component of the response is depends strongly on the subsurface electrical conductivity. The restricted measuring range of the EM-31 instrument is however a severe limitation on the usefulness of in-phase measurements in such cases. 
ER  -

