#TITLE_ALTERNATIVE#

• Main Author: BAITI (NIM: 12009013); pembimbing: Dr. Ir. Niniek Rina Herdianita, M.Sc., LUTFI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/18854
• Institution: Institut Teknologi Bandung

The research area is a potential geothermal field located in Duasudara area, Bitung, North Sulawesi. Geological mapping area is located on 734000-738000 mE and 166000-171000 mN (UTM Zona 51 N) with area of 20 km2. The research area is a volcanic region which is located on footslopes of Mount Duasudara and Mount Tangkoko. The objectives of the research area is to understand the geological condition and to know the distribution and the anomaly of Hg in soil and CO2 in soil-gas. <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> Lithology in the research area is products of Mount Duasudara. Volcanic activity of Mount Duasudara within the Pleistocene produced varied lithologies in the research area. The oldest unit is Tuff Unit, continued by Pyroclastic Breccia Unit and Andesite Lava Unit that were deposited during Pleistocene. The youngest unit is Lapilli Tephra Unit which was deposited on top of Andesite Lava Unit during the Holocene. Geological structures developed in the research area are Kayuwale Kecil Normal Fault and Pinasungkulan Normal Fault. These structures were occurred within the Pleistocene. The faults trend northwest-southeast and likely were caused by volcanic activity. These faults also were indicated by anomalous areas of Hg soil and CO2 soil-gas. <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> Analysis of Hg in soil and CO2 in soil-gas were carried out 127 soil and soil-gas samples. Anomalous areas of Hg and CO2 are known by determining the threshold value by the curve probability method. Value of Hg in the research area is 4-336 ppb with the threshold of 140 ppb, while value of CO2 range is 0,1-4,8% and the threshold of 3,5%. The distribution of anomalous areas of Hg and CO2 indicates high permeability zones to the northwest of the research area correlating with the geothermal activity.