Perpustakaan Digital ITB

Wayang Windu is an area at West Jawa, Indonesia that has active geothermal activity and part of it is being produced. Geothermal field development is indispensable to maintain sustainability of non-fossil-based electrical energy. Prospecting and exploration is part of activity in geothermal field development. In general, the local manifestations can be used to characterize the geothermal potential. One method that can be used to characterize the surface manifestation spatially is geostatistics multivariate method, i.e. Ordinary Cokriging (COK). The purpose of this study is to investigate the potential of surface manifestation around Wayang Windu by characterizing the physical parameters of its manifestations. In this study we also evaluate the results of the estimation of physical parameters using COK and Ordinary Kriging (OK). The primary data used for multivariate estimation is soil physical properties, i.e. roughness, conductivity, susceptibility, temperature, and pH which were measured directly in the nine zones of manifestation and seven zones of non-manifestation. While secondary data is derived from the result of data modeling of surface roughness back scattering intensity of ALOS PALSAR with two polarizations, known as: HV and VH. The result of correlation analysis between primary and secondary data are the roughness 0.09, conductivity C.!1, susceptibility -0.04, temperature 0.11, pH -0.21. Variogram models used for the five physical soil properties are nested structure with two spherical variogram model structures The variogram range (a) is 900 m for the local and 4000 in for the regional scales. The result of estimation showed that COK method is more effective than the OK method which was determined from the average estimation variance and linear regression parameters of estimated and true data. The average variance estimation of COK was lower than OK. Estimation map indicated that the area with similar soil properties of manifestation zone leads to the north side (Mt. Harunian Puncak Besar, and Mt. Malabar) and partly to the southwest side (Waringin Formation area). Generally the manifestation zones have characteristics of high roughness, high conductivity, and low pH.