Part 4. Plate boundary evolution in the Solomons region: Geochemistry of the Koloula Igneous Complex, Gaudalcanal

Abstract

The Plio-Pleistocene Koloula Igneous Complex is situated close to the south or Weather Coast of central Gaudalcanal and intrudes moderately dipping basaltic andesites, andesites and pyroclastics of the Suta Volcanics. Numerous small lenses of limestone, interbedded with the upper portions of the Suta Volcanics, yield Early Miocene foraminifera and the considerable thickness of underlying volcanics are thus considered to be of Oligocene to Early Miocene age (Hackman, 1971).