| 摘要 |
PURPOSE:To accurately enable analysis down to a deep underground structure, by receiving electromagnetic waves from an extremely ultralow frequency band to an ultralow frequency band, that is, the natural electromagnetic wave occurring from Schumann resonance, the electromagnetic wave oscillated from an omega station and the electromagnetic wave by an artificial oscillator by a receiver and measuring the apparent specific resistance value of underground up to the depth of several km. CONSTITUTION:An artificial oscillator 1 (about 7Hz-6kHz) is constituted of a generator 2, a boosting transformer 3 and an oscillator main body 4 etc. and the AC of the generator 2 is boosted to 500V.5A by a booster 3 and converted to DC by the rectifier in the main body 4. The main body 4 is arranged so as to be separated by about 1km from both electrodes 6 and ten kinds of frequencies of 7.8, 20.4...5,120Hz in total are oscillated. Next, a receiver 7 is arranged so as to be separated by about 30m from electrodes 11 and the coil 10 for a magnetic sensor is arranged so as to cross said receiver 7 at a right angle and the effective value of the electromagnetic field passed through BPF of a magnetotelluric meter main body 9 is digitally displayed by a digital display device 9 and further outputted therefrom. Subsequently, an oscilloscope 8 takes the wave forms of a wide-band and a narrow-band in a portable calculator 12 and the apparent specific resistance value of the ground is calculated and recorded. |
