EAGE Conference on the Future of Energy - Role of Geoscience in the Energy Transition

Projections of global population increase, consumption patterns and a general desire for welfare directly affect waste generation trends – the issue increasing simultaneously with limited land space, demand for new energy sources, resource depletion and environmental deterioration. Still, landfilling is among the applied waste disposal methods despite the negative ecological, social and economic impact. Besides operating sanitary landfills, millions of hectares are lost to society because of being used for legal waste landfilling or illegal dumping in the past. Closed landfills hide the vast amount of potentially recoverable resources regarding secondary materials (e.g., recycled metals, including highly valuable rare-earth elements) and energy recovery opportunities (e.g., by landfill gas collection and refuse-derived fuel extraction). At the final step, landfill transformation ends with land asset return to societal, economic and ecological needs, particularly considerable for overpopulated regions. This multi-integrational landfill transformation approach is grounded in experimental data and already realized successful revitalization examples. The methodology involves compiling field experiment results, laboratory investigation, life cycle analysis, and up-to-date economic estimations. Research-based outcomes are accountable for tangible and intangible assets expanding their functional applicability at selected case specifics.

Due to their unique chemical, magnetic, and luminescent properties, rare earth elements (REE) are necessary for high-tech enterprises. Ion Adsorbed Deposits (IADs) and Ion Adsorption Clays (IACs) are types of REE deposits formed by chemical weathering of REE-rich parent minerals. This study investigated soil profiles associated with the weathering of Late Triassic granitic bodies in the South Perak region of Peninsular Malaysia in order to advance our knowledge of the behaviour and distribution of rare earth elements during granite weathering.

Surface and subsurface samples were collected from eight sites. For laboratory analysis, the samples were dried, pulverised, sieved, and ground to the desired mesh size. In South Perak, there are vast exposures of granitic igneous bodies, and Ion Adsorbed Clays (IACs) contain sufficient concentrations of Rare Earth Elements (REEs) associated with this form of weathered rare earth deposits. At numerous locations, the total REEs content (TREE) exceeds the minimum threshold value of 300 ppm.

Naturally fractured carbonate reservoirs (NFCR) in Central Luconia have been considered as potential sites for carbon storage. Modelling the complex NFCR is difficult. Thus, analogue and comparative studies were conducted on Niah-Subis Limestone complex, Sarawak, to reduce the uncertainty in the fracture behaviour for Central Luconia karstified reservoirs. The fractures and karst features of were delineated by integrating the DEM lineament analysis and outcrop observation. Karst features such as dolines, caves, passages, and speleothems are highly influenced by the intersection of fractures, major orientation, and the surface and underground drainage system. In contrast, the karst dissolution also highly impacts the fracture complexity. This study shows that it is important to consider the effect of fractures and karstification during the estimation of potential carbon storage volume in Central Luconia.

The magnetic method is one of geophysical method that involves the measurement of the earth’s magnetic field intensity to identify a variation of rock on subsurface. Magnetic method usually used on mineral exploration, archeology, hydrothermal investigation, subsurface structure identification, and preliminary survey on geothermal. Especially on geothermal investigation, as we know, the geothermal system has several important components are needed to build sustainable geothermal energy, such as heat source, reservoir rock (permeable zone), flowing fluid (circulation or convention), geological structure, cap rock, and recharge area. The magnetic method combined with gravity method to identify subsurface structure and alteration mapping on geothermal survey. In this study, we would like to compare between land magnetic method and aero magnetic (drone and aero) method with several parameters like instrument used, acquisition technique, and processing technique. Then, we simulate the operation of geothermal investigation with coverage area 20 x 20 km to obtain the good combination geomagnetic method that can help to increase operational cost efficiency.

Geothermal fluid carries the heavy metal elements to the surface, one of which is arsenic (As). Arsenic can be found naturally in the earth crust, exist on soil and mineral then can be enter on air, water, and surface environment. In the form of gases, Arsenic are associated with temperature of rock, a volatile element, and which only release on high temperature. In this research, we would to study about arsenic characteristic, arsenic mobilization, and the scheme how arsenic gases can be release on surface with several conditions. Based on references, in Chile, at volcanic area, says the arsenic gas content release with the area which have a high temperature and have several conditions on manifestation type. Then from twice validation on different geothermal area on Indonesia, we get same correlation with the references. Based on that, we assume the arsenic gas content on geothermal area is correlated with high temperature of rock, in a general we called it a heat source.

Hydrogen is increasingly recognized as a solution for reducing greenhouse gas emissions. While it is primarily produced through thermochemical and electrochemical processes, natural occurrences of hydrogen in the subsurface have been observed worldwide. This suggests the potential for utilizing natural hydrogen as a green energy source. Studies have shown that natural hydrogen is commonly found in Precambrian cratons, ophiolite belts, and mid-oceanic ridges. However, the geological conditions that determine the presence of effective hydrogen systems in the subsurface are still unclear. This paper aims to summarize current knowledge on natural hydrogen generation, discuss critical geological conditions for hydrogen accumulation, and propose possible hydrogen accumulation models for exploration. Two conceptual models are proposed which accommodate different hydrogen generation mechanisms such as serpentinization, radiolysis, and pyrolysis, and offers a framework for guiding future exploration efforts.

The geochemical and geophysical studies were conducted on the weathered crust of granitic rocks in Bukit Pengkalan, Johor in order to assess the ion-adsorption type REE resource potential. Granitic rocks in the studied area consist of coarse grained granite with phaneritic texture with REE content ranging 176–236ppm. Profile of weathered crust P01 can generally be divided into horizon A (upper part) and horizon B (lower part) representing the lateritic horizon and weathered horizon respectively. In comparison, the weathering profile shows high content of Al2O3, Fe2O3 and LOI compare to the parent rocks. Average value of CIA for the weathering profile is 97. Based on La/YbN value, LREE is observed to be enriched toward the upper part of the weathering profile. Geophysical survey of 2D-resistivity has been carried out using Schlumberger protocol which consist of 4 survey line with 400m in length for each line. All survey line shows that the average soil thickness of the area is around 8m indicated by the resistivity value ranging from 400–3000Ωm. Some area shows the present of huge granite boulders near surface indicated by the resistivity value >2400Ωm suggesting that the rock in the area are more resistant to weathering.