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Key research themes
1. How can geochemical data interpretation tools improve the analysis of whole-rock geochemistry?
This research theme focuses on developing and utilizing data management and analytical software specifically designed for handling complex whole-rock geochemical datasets in igneous and metamorphic rock studies. Such tools aim to streamline calculations, normalize data, generate classification graphs, perform statistical analyses, and facilitate data visualization, thereby enabling more efficient and reproducible geochemical interpretations.
Key finding: Introduced GCDkit, a free, open-source R-based software with a graphical user interface designed to efficiently manage, recalculate, and interpret large whole-rock geochemical datasets. It integrates data import/export from... Read more
2. What are the principal controls and modeling approaches for reactive transport and pore-scale geochemical dynamics in porous media?
This research theme investigates the interplay of geochemical reactions with multiphase fluid flow, fracture mechanics, and pore structure heterogeneity in porous geological media. Advanced modeling at the pore scale and network levels combines imaging techniques and computational fluid dynamics (CFD) or numerical approaches to better predict mineral dissolution/precipitation, contaminant transport, and resource recovery dynamics. Understanding these controls is crucial for applications ranging from hydrocarbon recovery to contaminant remediation.
Key finding: Reviewed state-of-the-art pore-scale and pore network models that leverage high-resolution imaging techniques (e.g., micro-CT, SEM-EDX) to explicitly represent complex pore geometries and mineralogies. Demonstrated the... Read more
3. How can geochemical methods advance the exploration of deeply buried mineral deposits under cover materials?
This theme addresses the use of selective leaching, soil gas analysis, groundwater chemistry, and innovative geochemical surveying techniques to detect geochemical anomalies indicating buried mineralization obscured by thick overburden such as sediments, gravels, or colluvium. It explores dispersion mechanisms including electrochemical dispersion and hydrological transport, and integrates multi-element datasets with spatial analyses to refine exploration targeting in challenging terrains.
Key finding: Demonstrated the effectiveness and challenges of selective leaching methods (e.g., enzyme leach, Mobile Metal Ion (MMI)) in detecting mobile geochemical species over deeply buried mineral deposits beneath thick cover.... Read more
Key finding: Synthesized progress in exploration geochemistry emphasizing four areas including metal mobility mechanisms under cover, rapid field geochemical analyses (e.g., portable XRF), improved data integration, and advances in... Read more
Key finding: Extensive industry-supported case studies underscored the complexity in interpreting selective leach anomalies caused by dispersal of metals from concealed deposits through soil and groundwater pathways. The work accentuated... Read more
4. What geochemical techniques and insights are used to characterize geothermal systems and determine reservoir parameters?
This research theme focuses on the geochemical analysis of geothermal fluids, including major ions, trace elements, isotopes, and gas compositions to interpret reservoir temperature, origin, fluid-rock interactions, mixing processes, and geothermal potential. The integration of geochemical thermometers, isotopic data, and alteration mineralogy informs reservoir characterization, guides exploration, and supports sustainable geothermal resource utilization.
Key finding: Applied major ion chemistry, isotopic data, and classical geothermometers (Na-K, Na-K-Mg, quartz geothermometers) to constrain reservoir temperatures (~160-250°C) and fluid evolution processes. Results indicated meteoric... Read more
Key finding: Identified Na-Cl geothermal fluids as mixtures of ~20-25% seawater and 75-80% freshwater, interacting with volcanic rocks and magmatic CO2. Concordant chemical and isotopic geothermometers estimated reservoir temperatures... Read more
5. How does geochemical characterization of efflorescent minerals on mine tailings inform understanding of acid mine drainage and water chemistry impacts?
This theme investigates the mineralogy and geochemistry of soluble efflorescent crusts formed on mine tailings, focusing on their role in metal mobility, acid generation, and episodic contamination of downstream waters. Combining leaching experiments, field sampling, geochemical modeling, and mineralogical analyses improves understanding of the contribution of minor but reactive mineral phases to water quality, informing remediation and risk assessment strategies.
Key finding: Found that chemically distinct efflorescent crusts form on oxidized versus unoxidized tailings, releasing aluminum- and magnesium-rich or iron-rich acidic plumes respectively, with modeling tightly correlating mineral... Read more
6. How do geochemical mapping approaches at various spatial scales contribute to environmental, mineral exploration, and soil quality assessments?
This research theme examines systematic geochemical mapping conducted at global/continental, regional/national, and local scales. It evaluates sampling densities, analytical techniques, and data integration to reveal spatial distribution patterns of chemical elements in soils, sediments, and waters. The resulting maps and data inform mineral exploration targeting, agricultural land quality, urban contamination, and baseline environmental assessments.
Key finding: Reviewed and summarized nineteen studies demonstrating effective geochemical mapping across scales ranging from continental (sampling densities ~1 per 1600 to 8300 km2) to local (thousands samples/km2). Provided metrics... Read more
7. What are the key advances and limitations in geochemical modeling for mine site characterization and remediation?
Focused on the development and application of geochemical models to simulate mineral oxidation, precipitation/dissolution reactions, and aqueous speciation controlling mine water chemistry, including acid mine drainage processes. The theme also highlights model uncertainties, sensitivity to thermodynamic data, and the importance of integrating kinetic considerations and field data to improve predictive accuracy for remediation design and regulatory assessment.
Key finding: Provided synthesis of geochemical modeling capabilities, demonstrating that oxidation of pyrite leads to characteristic pH trends in mine waters influenced by Fe precipitation phases with saturation indices sensitive to... Read more
8. How can geochemical studies evaluate environmental and health risks associated with naturally occurring and anthropogenic materials?
This research theme encompasses geochemical characterization of environmental media (soil, water, geophagic materials) to quantify concentrations of toxic and essential elements, assess mobility, bioaccessibility, and risk of adverse health or ecological impacts. It combines trace element analysis, mineralogical investigations, risk modeling, and isotopic studies to inform public health and environmental management.
Key finding: Analyzed geophagic materials using XRF and ICP-MS demonstrating elevated concentrations of toxic elements such as As, Cr, and Pb that exceed recommended daily intake levels, coupled with alkaline pH and organic matter content... Read more
Key finding: Through hydrogeochemical characterization of thermal springs and geothermal waters, identified two main water types influenced by deep versus shallow circulation. The study detected elevated potentially toxic elements (e.g.,... Read more
9. What geochemical insights inform the safe disposal of high-level radioactive waste through actinide solubility and speciation studies?
This theme involves thermodynamic modeling and solid-phase analysis of actinide species, such as americium, in repository-relevant groundwater conditions. It aims to identify solubility-limiting phases, evaluate effects of pH and CO2 partial pressure on actinide mobility, and provide data critical for radionuclide transport models, safety assessments, and engineered barrier design in deep geological repositories.
Key finding: Modeled americium solubility and speciation under pH 6-11 and CO2 partial pressures relevant to Beishan repository using PHREEQC-3. Found that AmCO3OH·0.5H2O(cr) is thermodynamically stable and limits solubility at low levels... Read more