Individual Feedzone Characterization in Two Phase Geothermal Reservoir for Preliminary Indication While Drilling: A Case Study Dieng Field, Indonesia

Abstract

One of the key parameters for productive zone in geothermal reservoir is permeability. Permeability in most geothermal system is controlled by the presence of fractures. The result of well completion test is a guidance to define feedzone location which is controlled by permeability. Feedzone characterization is important for geological and reservoir analysis. Data in this study was taken from a production well in Dieng, Indonesia that has two phase reservoir system. During drilling, the analysis of drilling parameters, loss zones and borehole image gave an early estimation of permeable zones. The determination of fluid flow contribution and feed zone location will be confirmed by the result of pressure-temperature-spinner injection during completion test. Furthermore, initial reservoir characteristic, pressure, temperature, liquid interface and top of reservoir will be confirmed by pressure-temperature data during heat up process. The objective of this study is to find out preliminary individual feed zone characteristic while drilling to determine the potential feed zone. It is also complement for future geothermal well targeting based on drilling and subsurface aspects that potentially provide a productive zone in the future.