Latest progress of seismic survey method in hydrothermal uranium deposits exploration in China

Since 1950s, many non-seismic geophysical survey techniques, such as radioactive geophysical survey method, induced polarization (IP), high resolution magnetic survey method, AMT and CSAMT have been applied and have played a very important role in exploration for hydrothermal uranium deposits in China. However, up to the early stage of 21st century, seismic survey method has been hardly utilized in hydrothermal uranium deposits exploration. It is mainly due to the more complicated geological settings where hydrothermal uranium deposits occur than oil field, gas field or coal field does. These complicated geological settings involve many cases, for example, uranium ore form is complicated and its dimension is small, lithology composition is various, wave impedance difference between the medium on each side of the interface is small, ground surface conditions are rough and there are lots of high-energy interference waves. Since 2007, based on studies of hydrothermal uranium ore formation mechanism and ground surface characteristics in uranium ore field, seismic work group of BRIUG has carried out a lot of systemic tentative work on excitation type of seismic source, layout of geophones, data analysis and processing techniques, and has obtained obvious success in detection of ore-control factors, such as basement or faults with big angle of inclination. We are sure that seismic survey method developed by BRIUG will become one of the most important techniques for hydrothermal uranium deposits exploration within several years. (author)