Applications of gravity and magnetic methods in sandstone type uranium deposits

Sandstone type uranium deposits are covered by thick sediments in China, so radioactive anomalies is very weak at the earth's surface and prospecting is very hard. It is an urgent need for uranium prediction by using effective geophysical methods. This paper processes and analyzes gravity and magnetic anomalies of paleo-valley sandstone type uranium deposits, and we discover that gravity exploration which can recognize underground geological information including paleo-valley and buried uplifts helps to reduce exploration target areas of uranium. Meanwhile, weak magnetic anomalies are found at oxidation-reduction transition zones which is closely related with uranium enrichment, thus magnetic exploration has directly indicative function of this type uranium deposits. Therefore, in productive practice, it is important references for predicting exploration target areas of sandstone type uranium deposits by using effectively gravity and magnetic exploration. (authors)