| 摘要 |
PURPOSE: A device and a method for measuring a boundary of fresh water and salt water within underground water are provided to measure the position of a boundary of fresh water and salt water using a few sensors. CONSTITUTION: A device for measuring a boundary of fresh water(4) and salt water(6) within underground water comprises multiple sensors(1,2) and a monitoring unit(3). The sensors are each other separated within an observation hole drilled between the ground and underground water. And the sensors detect water pressure and specific electrical conductance of the underground water. The monitoring unit stores the water pressure and the specific electrical conductance. A density increase rate is calculated based on the measured specific electrical conductance. A position rate of the boundary between the sensors is calculated and output. |
