Magnetotelluric method aplication for conceptual modelling of geothermal system Pariangan West Sumatera

Abstract

Geological structures on Pariangan is influenced by the tectonic activities of the Sumatera Fault System, volcanic arc of Complex Mt. Marapi and Central Sumatera Basin, stratigraphy of this area was dominated by andesitic-basaltic lava and pyroclastic rocks (Quaternary). This study purpose to determine of geological structures, and heat source location of geothermal system in this area using Magnetotelluric Method (MT). 2-D resistivity model from MT method was combined with geological map for the conceptual models of geothermal system. Based on conceptual model, geothermal system in area was controlled by a couple of main fractures. These fractures are associated with faults in the northwest-southeast and southwest-northeast directions on geological map. It's also influenced the surface manifestation (e.g hot springs) and alteration mineral zone. Heat source was composed by metamorphic rock (slite rock and granit rock) at 1500-4000 musl as based rock. This heat source associated with activities of MT. Marapi.