WE PROPOSE A SOURCE-TO-SINK STUDY OF THE MINERALOGY AND GEOCHEMISTRY OF A CATCHMENT ON THE MARGINS OF A LAKE IN THE EAST AFRICAN RIFT VALLEY AS AN ANALOG FOR EARLY MARS AQUEOUS PROCESSES. THE OBJECTIVES ARE: (1) DETERMINE THE MINERAL AND GEOCHEMICAL SIGNATURES OF A CATCHMENT WITH A DELTA AT LAKE NATRON TANZANIA WHERE THE HEADWATERS ERODE THROUGH MG-CLAY RICH PALEOLAKE DEPOSITS AND BASALTS (2) IDENTIFY