LAHENDONG GEOTHERMAL FIELD BOUNDARY BASED ON GEOLOGICAL AND GEOPHYSICAL DATA

Lahendong geothermal field is located in the northern part of Sulawesi island. The first exploration stage was started in the early 70’s. Numerous geophysical investigation were carried out such as Gravity, Magneto Telluric (MT), Resistivity and Mise-a-lamasse (MAM) methods. However, the precise geothermal boundary is not identified clearly. This paper will emphasize on geophysical data processing in determining the geothermal boundary at Lahendong area. In geothermal exploration, which use several geophysical methods, no single method can give satisfactory result in featuring the subsurface geometry. Therefore, we have to integrate all of the acquired geophysical data to get a realistic model for the studied geothermal field. The Lahendong geothermal field reality is unique, consequently our geophysical model parameter must be inferred from this unique realization. This paper, we demonstrated the advantage of integration the geological and geophysical data of Lahendong area. Knowledge of geology in the prospective area is fundamental to develop a correct model of the geothermal reservoir. Development of the geothermal models is an iterative process.