Evaluation of landsat imagery for Coastal-Lowland uranium exploration

Abstract

Computerenhanced Landsat images of northwestern Sri Lanka have been used to define facies changes and linear features along a belt of structural basins. This was possible because of the relation between the vegetation density and the local substrate. A major lineament coincident with an alignment of basin axial zones was discovered based on the convergence of evidence derived from both spacial and spectral data manipulations. This basin axial lineament is believed to be related to uranium mineralization in the following ways. 1) It marks a regional facies change, which is necessary for the efficient trapping of dissolved uranium. 2) It marks an abrupt change in regional slope and in hydrodynamic gradient. 3) It marks an abrupt change in structural domain. 4) It marks an abrupt change in geochemical gradient. The abovementioned conditions favour a continuing concentration of uranium through long geological time.