Dimensionality analysis of Magnetotelluric Data in 3D synthetic model representing a reservoir of Carbon Capture Storage (CCS) Nurhasan1*, Andika Pratama1, Gita Amelia Marianto Limbong1, Wahyu Srigutomo1, Enjang Jaenal Mustopa1, Bagus Endar B. Nurhandoko1
Bandung Institute of Technology
Abstract
Carbon Capture and Storage (CCS) is one of the key climate change mitigation technologies aimed at capturing carbon dioxide (CO₂-) emissions from fossil fuel power plants and heavy industries, followed by secure long-term storage in deep geological formations. One of the keys to the successful implementation of CCS strongly depends on the geological characteristics of the subsurface, including lithology, porosity, permeability, and fluid content, to ensure sufficient storage capacity and long-term containment of the injected CO₂-. Previous studies have employed gravity and seismic methods to characterize storage formations- however, these methods often face limitations in in detecting parameter having contrast caused by fluid saturation changes following CO₂- injection. To address these limitations, this study utilizes the Magnetotelluric (MT) method, an electromagnetic geophysical technique capable of probing several kilometres below the surface and sensitive to resistivity variations associated with fluid saturation changes, making it highly suitable for CCS applications in Indonesia. This research incorporates dimensionality analysis of MT data to analyse the characterization of the CCS reservoir model. The analysis involves calculating dimensionality parameters such as phase tensors, tipper vectors, skewness values, and strike directions to determine subsurface structural complexity and validate the appropriateness of 1D, 2D, or 3D structure, using Python-based processing. Furthermore, changes in resistivity due to CO₂- injection are evaluated using a modified Archie^s Law, considering the supercritical conditions of CO₂- at depths exceeding 800 meters. The results demonstrate that the MT method is effective in identifying potential CO₂- storage zones and is highly sensitive to resistivity variations due to fluid saturation changes, including those induced by CO₂- injection.
