Spatial mapping of hydrothermal alterations and structural features for gold and cassiterite exploration

Abstract

Mineral deposits show an intrinsic relationship with hydrothermal alteration and structures features which may be invaluable for regional scale exploration survey using spaceborne data. Within the Kaiama sheet, spatial data such as Landsat 8 OLI and ASTER digital elevation model were processed by enhancing hydrothermal alteration and geological lineaments. Image processing techniques such as band ratio and principal component analysis were used for alteration mapping, while Fry analysis and distance correlation analysis were applied for evaluating the structural attributes of gold and cassiterite mineralization. Evidence from image processing suggests the presence of clay and iron alterations within zones of known mineral deposits, while structural studies by application of the Fry and distance correlation analysis suggests gold and cassiterite occurrence is effectively controlled mainly by a NE-SW tectonic trend. The proximal association of gold and cassiterite mineralization with geological structures and hydrothermal alterations may be invaluable for defining a digital exploration criterion for the Kaiama sheet.