Walk-away Vertical Seismic Profiling (WVSP) Simulation for Monitoring CO2 Injection in Gundih Field

• Main Author: Augusta Gunawan, Kevyn
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/41944
• Institution: Institut Teknologi Bandung

Indonesia has committed to contribute in reducing greenhouse gases emission, mainly in the agricultural and forestry sector. Energy sector contribution in reducing the greenhouse gases is only 22% but could be improved to 33% with the funding from other countries. Carbon Capture Storage (CCS) is believed to be the only way to reduce greenhouse gases emission on a big scale. In Indonesia, CCS has not been a way to reduce greenhouse gases emission. However, this could change if there is help from other international countries. Therefore, since 2012 Bandung Institute of Technology (ITB) ITB has started the first CCS pilot project in South and Southeast Asia, that took place in Gundih Field, Central Java. This upcoming plan is to inject CO2 in supercritical phase into the carbonate build-up reservoir on Kujung formation. To be able to inject CO2 inside the formation, a lot of studies are needed to know the targeted formation capabilities. The injection target is between 3000-3500 m. Before and after the injection is done, there is a need for a method to monitor the injected CO2. Walkaway Vertical Seismic Profiling (WVSP) simulation method is used for this study. The receivers which are assumed to be fiber optic cable are located along the borehole, while the source is located on the surface along one seismic survey line. Based on the reservoir simulation, CO2 plume geometry is considered thin with the thickness of 70 m for 2 years of injection with the injection rate of 800 ton per day. As for the same injection rate of CO2 for 10 years, the thickness of the will be 350 m located in the brine zone of Kujung formation. Simulation is done by using NORSAR 2D software with the raytracing method. After that, data processing is done to give the results of seismic depth section using ProMAX software. The results have indicated that the WVSP method has successfully shown the difference between the reflected plume CO2 for 2 years and 10 years after injection monitoring. Therefore, WVSP monitoring method is recommended to be applied in the Gundih CCS Pilot Project.