In December 2019, the underwater transient electromagnetic method exploration geophysical exploration of the Wanzhou Urban Water Supply River Crossing Pipeline Project explored geophysical exploration and lowered the transmitting and receiving coils to the bottom of the river for detection (up to 100 meters). It is required to ascertain: the thickness of the Quadruple overburden and the undulating morphology of the bedrock face; stratification of shallow strata above 100m; Detect the location and width of latent faults and fracture fracture zones; It focuses on the distribution location and influence range of latent fault fracture zone.

Construction site of underwater transient electromagnetic method 

Line2 Apparent resistivity contour plot of underwater transient electromagnetic method

It can be seen that the apparent resistivity contours of regions A and B are out of order, and the apparent resistivity values are low, and it is speculated that the bedrock in this area is relatively broken, and the thickness of the river bottom overburden is about 5-10m.