Contrasting distribution of trace elements between representative antimonydeposits in southern China

The Xuefeng uplifted belt and the neighboring Xikuangshan region of souther n China is the largest antimony producing area in the world. The mineralizi ng solution which was responsible for the antimony deposition is considered to be derived mainly from deep crustal fluids during a large tectonic move ment of the Jurassic time, We analyzed trace elements of ore minerals and f luid inclusions from this area by CSIRO's micro-PIXE to understand characte ristics of the mineralizing solution. We selected three representative "sup er-large" deposits, one in the Xikuangshan area and the others within the X uefeng belt: (1) Xikuangshan (simple Sb) which is structurally controlled b y large-scale transcrustal faults and fractures, and mainly hosted by Limes tone; (2) Wuxi (Sb-Au-W), embedded in slate and structurally controlled by large-scale faults and fracture; and (3) Banxi (simple St?) which is hosted by slate and controlled by local fractures. Our preliminary result indicat ed that the trace element distribution is highly contrasting for these thre e deposits corresponding to each geologic setting. Our case study showed th at being combined with field evidence, microPIXE can contribute to understa nd large tectonic movements and to establish an effective exploration model for super-large mineral deposits. (C) 1999 Elsevier Science B.V. All right s reserved.