[H-TT18] New Developments in Shallow Geophysics

[HTT18-03] Repeated experiments of towing electromagnetic method using an uncrewed ground vehicle on a river embankment

*Ryosuke Umezawa¹, Motoharu Jinguuji¹, Toshiyuki Yokota¹ (1.National Institute of Advanced Industrial Science and Technology)

Keywords:resistivity, river embankment, electromagnetic method, UGV

Slingram type electromagnetic methods are non-destructive methods to obtain resistivity information at relatively shallow depths. One of these systems is the multi-coil electromagnetic survey system, that can obtain information at different depths by having several receiver coils at different distances from the transmitter coil. This system has been studied in combination with uncrewed ground vehicles. Since this method has the characteristics of non-destructive and efficient survey, it is considered effective for surveying in long structures, such as river embankments. However, it is important to understand the weak area of river levees in the survey. Therefore, we conducted repeated experiments using a method combining an uncrewed ground vehicle and a slingram electromagnetic survey to investigate whether it is possible to identify the weak areas.
In this study, measurements were conducted on the left embankment of a Nishinire River in Koga City, Ibaraki Prefecture. In this measurement area, water seepage into paddy fields has been confirmed. Measurements were conducted several times at different seasons when the water level of the river was different. Using these results, the resistivity structure was obtained by inversion and discussed.