The Most Preferable Gravity and Magnetic Survey Design for Medium Enthalpy Geothermal Field. Case Study: X Geothermal Field, Philippines

Abstract

Geophysical methods such as gravity and magnetic can be used to figure out permeable zone (reservoir) at geothermal field. Several survey designs of gravity and magnetic methods at X geothermal field had been applied to determine the most preferable result at medium enthalpy geothermal field. Two types of gravity design survey are based on the interval of the nearest station points: the first is 250m and the second is 500m. The first magnetic design survey is based on line survey meanwhile the second magnetic design survey is using gravity grid with interval 250m. The interval of 250m design survey at gravity is better for resolution than 500m design survey. The result for line survey at magnetic method is more suitable for mapping local anomaly, while the grid design survey is more suitable for regional mapping.