Integrating PALSAR and ASTER data for mineral deposits exploration in tropical environments: a case study from Central Belt, Peninsular Malaysia

Abstract

Remote sensing investigation for mineral deposits exploration in tropical environments is not completely implemented due to obstacles imposed by tropical climate. Recent challenge is to use the most suitable recent generation of remote sensing data and image processing approaches for the detection of lithological units and structural features associated with epithermal and polymetallic vein-type mineralisation, which are concealed by tropical rainforest. This research investigates the integration of the Phased Array type L-band Synthetic Aperture Radar (PALSAR) and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite data for geological mapping applications in tropical environments. The eastern part of the Central Belt of Peninsular Malaysia with high potential for gold prospecting has been investigated as a case study to identify structural features and mineral assemblages using PALSAR and ASTER data. Adaptive local sigma and directional filters were applied to PALSAR data for detecting geological structure elements in the study area. Vegetation, mineralogic and lithologic indices for ASTER bands were tested in tropical climate. Lineaments (fault and fractures) and curvilinear (anticline or syncline) were detected using PALSAR image map of directional filters (N–S, NE–SW and NW–SE).Vegetation index image map show vegetation cover using ASTER visible and near-infrared radiation (VNIR) bands. High concentration of clay minerals zone was detected using image map derived from ASTER shortwave infrared (SWIR) bands. ASTER thermal infrared (TIR) bands produced image map of the lithological units. Results indicate that data integration from PALSAR and ASTER sources enhanced information extraction for geological mapping in tropical environments. The study presented here encourages further applications of satellite remote sensing data integration for mapping structural elements, hydrothermal alteration minerals and lithological units associated with epithermal and polymetallic vein-type mineralisation in tropical environments.