1. Shandong Geological Prospecting Institute of China Chemical Geology and Mine Bureau, Jinan 250013, China 2. Binzhou University, Binzhou 256603,China
In view of the fact that a certain copper mine in Chile is with great terrain elevation difference, sharp vertical cutting and low efficiency in running way of conventional symmetrical schlumberger units, this paper brings forward the proposal of utilization of complex unit combining symmetrical four-electrode and central gradient, that is to say, small polar distance is provided with symmetrical four-electrode detection device whereas large polar distance is provided with central gradient detection device. In the same sounding profile of the mine, the comparison of the sounding inversion results by symmetrical schlumberger unit and complex unit (symmetrical schlumberger + central gradient) indicated that the inversion results of the complex unit equals to the sounding effects of symmetrical schlumberger unit, but the complex unit is more efficient and more suitable for construction in complicated topography areas.
Loke M H . Rapid least-squares inversion of apparent resistivity pseadosections by a quasi-Newton method[J]. Geophysical prospecting, 1996,44:131-152.
doi: 10.1111/gpr.1996.44.issue-1
[9]
Loke M H . A comparision of smooth and blocky inversion methods in 2D electrical imaging surveys[J]. Exploration Geophysics, 2003,34:182-187.
doi: 10.1071/EG03182
Zhou B, Greenhalgh S A . Rapid 2-D/3-D crosshole resistivity imaging using the analytic sensitivity function[J]. Geophysics, 2002,67(2):755-765.
doi: 10.1190/1.1484518
