STUDY OF WELL CONNECTIVITY AND SUBSURFACE STRUCTURE INTERPRETATION USING TRITIUM TRACER IN WAYANG WINDU GEOTHERMAL FIELD

• Main Author: Apriani, Lestari
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/36303
• Institution: Institut Teknologi Bandung

Tracer breakthrough analysis is a method which shows the connection between the injection and production wells to determine the characteristics of permeability between the production and injection wells. The analysis of tracer breakthrough in the research area shows high connectivity between MBE-5 injection well in the northern part and WWT-2 production well in the southern part, which have long distance that indicates a large permeability control between both wells. Being based on it, this study aims to identify the types of permeability that controls interwell connection in the study area. The research area is located in Wayang Windu Geothermal Field, Pangalengan District, Bandung Regency, West Java Province. The initial stage is identifying the number of geothermal systems based on volcanostratigrapy, gravity and geochemistry studies. If it consists of one system, the major permeability that controls the connection between MBE-5 injection well and WWT-2 production well is primary permeability. However, if it consists of two systems, then the main controlled of interwell connection is secondary permeability due to tectonic processes. The next step is analyzing tracer trititum based on the breakthrough curve of the production wells. The production wells that have breakthrough tracer with high tritium concentration, the fast time and a long distance from injection well are interpreted as a result of fault structure. Fault obtains from the tracer analysis is integrated with validated subsurface fault structures. The results of the data integration are the qualifications of mapped and unmapped subsurface structures in the research area. Being based on the analysis above, the Wayang Windu Geothermal Field consists of two geothermal systems, namely the northern and southern geothermal systems. Hyphotetically, the connectivity between the MBE-5 injection well and the WWT-2 production well is controlled by deep fault structure as a permeability pathway.