SEMAT ITB Discusses the Future of Energy: Petrology Experiments for Supercritical Geothermal Systems and Carbon Capture
By Nasywa Hafizh Pandyanayaka - Mahasiswa Teknik Geologi, 2022
Editor Anggun Nindita
BANDUNG, itb.ac.id – The Geological Engineering Study Program of the Faculty of Earth Sciences and Technology at Institut Teknologi Bandung (FEST ITB), in collaboration with the Indonesian Association of Geologists (IAGI) and Tohoku University, held a Friday Seminar (SEMAT) at the Hilmi Panigoro Room, Geological Engineering Building, ITB Ganesha Campus, on Friday, February 28, 2025. This session of SEMAT featured a joint discussion with Tohoku University under the theme: “Experimental Petrology for Supercritical Geothermal Systems and Carbon Capture and Storage: Insight for a Sustainable Future.”
Dr. Astin Nurdiana, a faculty member of the Geological Engineering Study Program at ITB, explained that one of the key scientific approaches to achieving a sustainable future lies in the field of experimental petrology. This type of research focuses on studying the properties and behaviors of rocks and minerals under physical conditions that closely resemble those found naturally within the Earth. The primary goal is to gain a deeper understanding of geological processes such as volcanism, plate tectonics, and other geological events.
“Experimental petrology is used to explore the Earth's interior, investigate magmatic and volcanic activity, examine mineral formation, and support both geochemical and geophysical modeling,” she stated.
Typically, the experiments involve what is known as fluid-rock interaction—mixing fluid and rock at a certain temperatures and pressures. One of the current research focuses is the exploration of supercritical geothermal systems. “The term ‘supercritical’ refers to the phase of fluid within these systems,” she explained. “As the temperature increases, the fluid enters a supercritical phase—where its pressure and temperature exceed critical thresholds, resulting in a significantly higher energy potential.”
One notable example is the geothermal field in Kakkonda, Japan, where granite rock formations exhibit unique properties at certain depths. In the deeper sections of this site, supercritical fluids reaching up to 500°C have been identified. These granite rocks contain microscopic-scale pores, which are essential for fluid flow—this phenomenon is commonly referred to as feldspar replacement.
To understand this further, hydrothermal experiments have been conducted by replacing plagioclase or feldspar minerals with fluid to examine how porosity develops in response to varying fluid compositions. Different minerals exposed to the same fluid composition produce distinct textural outcomes. The findings suggest that microporosity from feldspar replacement can be enhanced using specific reactive fluid compositions, which in turn improves fluid pathways and energy storage capacity. This discovery holds significant promise for advancing the development of supercritical geothermal energy systems.
In addition to renewable energy solutions, efforts to achieve net-zero carbon emissions are also being pursued through Carbon Capture and Storage (CCS) technologies. “Several regions capable of storing carbon dioxide are typically underlain by basaltic formations, such as those found at mid-ocean ridges. These rock types contain elements that readily react with CO?,” she added.
One industrial innovation currently under development is carbon mineralization using industrial waste. This method offers a breakthrough solution for permanently storing CO? by converting it into stable carbonate minerals, providing a secure and long-lasting form of carbon sequestration.
Reporter: Nasywa Hafizh Pandyanayaka (Geological Engineering, 2022)
Translator: Malika Fatima Lawe (Microbiology, 2022)
