Perpustakaan Digital ITB

Field investigation of the potency of alluvial tin deposit has been conducted in Bangka Island. The investigation used Ground Penetrating Radar (GPR) and lnduced Polarization (P) to identify the tin alluvial deposit. It aims to detect the residual of alluvial tin deposit in the ex-artisanal mine. GPR offered high-resolution imaging capabilities to distinguish the layer sedimentary and measuring the thickness. The method was able to rapidly differentiate the unstable and stable layers. providing continuity for visual interpretation. While IP method was used to determine the depth of deposit by resistivity and chargeability properties. The method provided the presence of conductive deposit used to distinguish each layer on the depth. GPR radargram and IP imaging were correlated to the former borehole data to aid an interpretation of different layer of residual or insitu deposit. The alluvial layer from logging data was divided into two main layers. i.e. sandstone contains tin ore and clay contains tin ore. The potential alluvial deposit was determined from the thickness and tin content on each alluvial layer. As a validation of pro?ling GPR. check borehole was required on each line to recognize the alluvial layer and its tin content. The identi?ed residual tin reserve was evaluated to quantify the volume of alluvial tin which determines the feasibility of mining activity.