The method of mine detection is a wide spectrum (1 mhz-1ghz) electromagnetic technique used to determine the distribution of underground media. Mine detection missions use one antenna to launch high-frequency wideband electromagnetic waves, while another antenna receives reflection waves from underground media interfaces. When the electromagnetic wave is transmitted in the medium, its path, electromagnetic field strength and wave shape will vary according to the electrical nature and geometry of the medium adopted. Therefore, the structure of the medium can be inferred from information on the range and wave shape of the time of travel (also known as the two-way journey) received。
Mine detection methods, with a very small or even combined distance between the launching antenna and the receiving antenna. When the local layer is less inclined, the entire path of the reflection wave is almost vertical. Thus, the tectonic pattern of the subterranean layer is reflected in changes in the tectonic reflection time at different positions of the line。
Mine detection is carried out with a high frequency and is dominated by bit transfer currents in geological media. As a result, high frequency (hf) wide-banded electromagnetic waves are transmitted with little frequency in substance, and the speed is largely determined by the media's media nature. Thus, there are many similarities between the theory of electromagnetic wave transmission and that of elastic wave transmission. The two follow the same pattern of swing equations, except for differences in the physical significance represented by the variable in the swing equation. The similarity of radar and seismic waves in kinetics can be used in data processing. When mine detection records use the same measuring devices as seismic records, many of the techniques already widely used in seismic data processing can be processed directly using a thousand mine surveys, with simple changes in input parameters and rescaled. The results of seismic reflections are often used in our discussions below when mine detection data are being inverted。
Mine detection is a geophysical exploration method using uhf (10-10hz) pulsed electromagnetic waves to detect the distribution of underground media. It has been shown that it can distinguish the distribution of the media at the 10-`m scale below ground, so that mine detection methods have extremely wide application prospects with their unique high resolution in sub-surface and ultra-subsurface geological surveys。
In the 1960s, our country began to study instruments and methods for mine detection, and progress was slow in monitoring the level of equipment and processes at that time. In the late 1980s and early 1990s, the technology was increasingly applied in many of the leading cities, such as engineering geological surveys, basic engineering quality tests, disaster geological surveys and archaeological surveys, and had achieved significant social and economic benefits, as the level of instrumentation in the country increased and advanced instruments were introduced abroad. On the basis of more than four years of applied practice at the chinese university of geology (wuhan), a more comprehensive and systematic summary of mine detection theories, methods of work, data processing and interpretation and the application of their methods has not yet been prepared, and a book entitled “mine detection techniques and applications” has been produced。
This book provides a brief introduction to the doctrine of mine detection techniques; provides a detailed description of mine detection techniques; and describes the methodology applicable to mine detection data processing, drawing on the processing of reflective seismic information; examples of applications in a number of areas have been identified with detailed information. The purpose of this book is to provide -- a practical reference book for applied geophysical technicians involved in mine detection, as well as for theoretical researchers, teachers and students of higher geological institutions。
