Geology of Arjosari Geothermal Area, Pacitan, East Java
Untung Sumotarto, Fajar Hendrasto, Mira Meirawati, Izzuddin Azzam
Universitas Trisakti
Abstract
A geological survey has been performed at Arjosari geothermal area, Pacitan, East Java. Hot springs, rock alteration, and other surface manifestations indicate possible geothermal energy potential of the area. Geologically four main rocks are found in the area. Those are sandstone and volcanic breccia of Mandalika Formation, volcanic rocks of Arjosari Formation, igenous rocks on the bottom of the area and alluvium deposit. Regionally many igneous rocks are exposed as intrusive genetic. The volcanic and igneous rocks found in that area are faulted and have fractures making conductive and convective heat transfer happened causing the formation of hot springs, rock alteration and other natural geothermal characteristics. With the existence of various volcanic and igneous rocks, the surface manifestation of hot springs and other rock signs, it can be concluded the geothermal system of the area.
Keywords: volcanic and igneous rocks, rock alterations, hot springs
Topic: Geology