Electromagnetic transient underground radar (ETUR) for geophysical exploration

In simplest terms, ETUR is a conventional radar without the carrier. A narrow pulse is transmitted into the ground and a pulse scattered from any asymmetrical target (w.r.t. the antenna axis of symmetry) is observed on an electrically isolated receiving antenna. The pulse width is sufficiently narrow so that the transmitted pulse magnitude has become negligible when the scattered pulse arrives at the antenna terminals. These and other essential features of the ETUR system will be discussed. By careful design, these two mechanisms, the short pulse width and the antenna isolation provide a reasonably clear range window. This allows the reflected pulse to be observed in real time on the oscilloscope display. Experimental results will be presented in terms of this reflected pulse. These include the reflected pulses obtained from infinite metal and plastic pipe, finite length pipes and other finite sized objects, geological structures such as faults, joints and fractured rock zones, tunnels and coal mines. A commercial version of ETUR using a trade name Terrascan for the detection of buried pipes should be available at the time this paper is presented.