METALLOGENIC CONDITIONS AND PROSPECTING DIRECTION FORIN-SITU LEACHABLE SANDSTONE-TYPE URANIUM DEPOSITS IN THE MESO-CENOZOIC BASINS OF NORTHEAST CHINA

The Meso-Cenozoic basins in Northeast China are major exploration region for in-situ leachable sancl-ston-type uranium deposits. Since 1996, large amounts of borehole drilling have been performed in the basins during the regional reconnaissance (1:500 000-1:200 000) for prospecting in-situ leachable sandstone-type uranium deposits. The theory and method of regional prognosis criteria for the sandstone-type uranium deposits are adopted to study the metallogenic conditions of Songliao and Hailar basins. The favourable horizons and potential areas are proposed, which provide a foundation for locating the in-situ leachable sandstone-type uranium deposits.