APPARATUS FOR AIRBORNE ELECTROMAGNETIC SURVEY AND METHOD OF SURVEY USING THE SAME

摘要

[PROBLEMS] To investigate underground resistivity structure accurately without being affected by large primary magnetic field. [MEANS FOR SOLVING PROBLEMS] A transmitter supplies current to a loop antenna. The current generates a primary magnetic field. The primary magnetic field causes an eddy current underground. Eddy currents generate a secondary magnetic field. The magnetic sensor detects a magnetic field including a secondary magnetic field. The magnetic sensor is disposed along the position where the vertical component of the primary magnetic field disappears. The distance from the magnetic sensor to the loop antenna is 0.5 times or more the diameter of the loop antenna.