Sokoria, East Indonesia: a Classic Volcano-Hosted Hydrothermal System

Abstract

A geoscientific survey was carried out over the Sokoria region of Flores Island, East Indonesia to assess its potential for small scale geothermal development to supply the electrical requirements of the region. The Kelimutu volcanic complex is a classic example of a volcano-hosted hydrothermal system. The complex hosts both an active volcanic component and a high temperature hydrothermal system. Geochemical surveys that at highest elevations, two of the Kelimutu Lakes contained a magmatic component while the third had characteristics of high elevation steam condensates from the geothermal system. With decreasing elevation, the chemistries of fumaroles and hot springs extending over an area of 80 sq indicated mixing of both the magmatic and condensate components with neutral chloride outflows. This geochemical model was supported by resistivity data which indicated high temperatures north of the Mutabusa fumarolic area and an outflow along the Lawongalopolo River Valley in the south west of the prospect.