The application of EH-4 dual-power electromagnetic system to evaluating the shallow groundwater
XIE Zhi-Feng1, DU Fa1, GAN Bin2
1. No. 2 Institute of Geology and Mineral Exploration of Gansu Bureau of Geology and Mineral Exploration and Development, Lanzhou 730020, China;
2. Geophysical Exploration Institute of Qinghai Bureau of Environmental Geology Exploration, Xining 810007, China
Talatan area in Gonghe basin of Qinghai Province is rich in Quaternary unconsolidated rock pore water, characterized by similar aquifer and aquiclude resistivity. Therefore, the common ground electric prospecting results look fuzzy, and it is difficult to precisely determine the groundwater level and the thickness of the aquifer. Using dense frequency and high vertical resolution characteristics of the EH-4 dual-power electromagnetic system, the authors made an effective trial above the known well. Based on a comparison with the borehole data, the authors calculated the empirical correction coefficient, then carried out MT "十" shape profile measuring and Bostick 1D inversion and EMAP 2D inversion to profile data in the work area, and checked empirical coefficient of the inversion results. Through synthesizing 1D and 2D inversion results, the authors formed inference geological section to quantitatively identify the buried depth and aquifer thickness of the groundwater, and successfully determined well spacing. The expected water inflow was obtained at the designed depth, and the interpretation accuracy of MT method was greatly improved.
谢志峰, 杜发, 甘斌. 利用EH-4双源电磁系统评价浅层地下水[J]. 物探与化探, 2018, 42(2): 253-258.
XIE Zhi-Feng, DU Fa, GAN Bin. The application of EH-4 dual-power electromagnetic system to evaluating the shallow groundwater. Geophysical and Geochemical Exploration, 2018, 42(2): 253-258.