Abstract
Three types of groundwater flow are examined by velocity-meter measuring and resistivity logging to evaluate flow velocity.
Resistivity logging is easy to define groundwater flow in a borehole on the basis of variations in resistivity. As flow amounts, depths below water level, salt concentrations in solution for logging, quality of in flow water, and flow types could sometimes affect variations in resistivity during testing, the rate of variation in resistivity is difficult to serve as a criterion to evaluate flow velocity in a borehole.
The velocity-meter which provides simultaneously flow speed and derection in a borehole has been tested. It takes five minutes or a little more for the velocity-meter to gain data at each measuring point. The mean speeds measured vary with only flow amounts and about equal 0.9 times theoretical ones in the experiments, showing that the velocity-meter can provide data to complement results of resistivity logging.
