Research of loop character and transition process of sea-floor transient electromagnetic method and experiment in lab

To apply the controlled source time-domain electromagnetic method in the sea-floor exploration, transmitting and receiver sensor should be wrapped in a mass of small loops. This paper makes an analogy of the effect of transmitting current back edge from the electric character of transmitting coil, makes a theoretical analysis and in-lab experiment about parameters of receiver coil and its transient process, calculates the first-field and second-field inductive electromotive force theoretically when receiver coil circuit model after the transmitting current ramp form descends and turns off, makes an analogy of the method to eliminate oscillation of receiver coil, and do an experiment about in-lab matching resistance of fixed receiver coil.