Systematic Prospection Stage For The Uranium Resources Inventory In Onsom-Inau Sector West Kalimantan

The systematic prospection based on the anomalies of metasediments rocks was meant to inventory U resources for getting anomalies data, litologies and geological structure by systematics method on the relation to U mineralization. The examination method enclosed litology and tectonic observation, rocks and soil radiometry and rocks sampling. The examination method enclosed litology and tectonic observation, rocks and soil radiometry and rocks sampling. The examination area as wide as 15 km2 was occupied by metasediments rocks and igneous rocks. There were three kinds of fault group that be could interpreted as normal fault group on NE-SW direction, over thrust fault group on NNW-SSE direction and conjugate wrench fault group on NW-SE direction. U mineralization associates with pyrite, quartzmolybdenite, tourmaline magnetite and controlled by fault structure. Total content of U were about 2l.60 - 929l.66 ppm and 26.86 - 561,04 ppm for thorium. The general direction of outcrops a distribution was equal with the general direction of soil anomalies, that was NW-SE. Based on domination anomalies, distribution U mineralization which were controlled by fault and associated with sulfide mineral and U contents, the area of 0.35 square kilometres in Onsom sector was investigated geophysically for understanding of uranium mineralization body form subsurface