Chair: Carmina Jorquera, Teck Resources Ltd.

Description: This thematic session will be focused on, and open to studies related to the use of geochemistry for exploration. It will cover traditional techniques based on stream sediment, soil, rock chip sampling, lithogeochemistry, as well as more innovative techniques oriented to exploration in areas of transported overburden, partial extractions, biogeochemistry, mineral chemistry, hydrogeochemistry and any other novel uses of geochemistry applied to mineral exploration (at any scale). Geochemistry has been a long standing and traditional tool in mining exploration, in which advancing improvements of analytical techniques allow for new and novel opportunities to face the increasing challenges of exploration. Combination of geochemical exploration techniques with any other tools such as geophysics and mineral spectroscopy determinations is encouraged within an integrated geological framework.

Chair: Andrew Menzies, Bruker Nano GmbH.

Description: The traditional use of geochemistry and mineralogy in mining exploration has evolved over time together with analytical capabilities, however the application of results has always been dependent on the turnaround time and sample processing capacity of internal or commercial laboratories. Consequently, this can have an impact on the timeous evaluation of exploration projects and can undermine the ability for quick decisions in the field.  The advent and continual development of field portable technologies and their application to direct on-site analytical determinations has provided exploration geologists with a multiplicity of tools to assist quick decision making. This thematic session will focus on data quality and case studies of applications of field portable technologies in mining exploration, such as portable XRF, LIBS, XRD, spectroscopy, and any other on-site field geochemical analytical technologies.

Chair: Álvaro Egaña, Universidad de Chile.

Description: The use of multi element geochemistry in the mining industry, coupled with geological, mineral, geophysical and spectroscopy data, from exploration to resource and reserve estimates, and applications of multi element geochemistry to quantitative mineral characterization among many other uses, generates ever increasing amounts of information, in which data processing by Big-data science techniques offers novel and very powerful opportunities to perform data integration, multivariate analysis, data modelling and interpretation. This thematic session will focus on, and welcome studies related to the use of data science, machine learning, statistical learning, or deep learning techniques in the mineral industry, with particular attention to those associated with maximizing the use of multi-element geochemical data integrated with other sources of information.

Chair: Brian Townley, Universidad de Chile.

Description: This thematic session is oriented to studies that evaluate the value of multi-element geochemistry as a tool for semi-quantitative to quantitative bulk mineral characterization in geological, resource and geo-metallurgical modelling of ore deposits, applied to the characterization of lithology, hydrothermal / supergene alteration types and intensities, as well as mineralization. This session will be focused on applications that permit numerical classification techniques for mineral characterization in ore deposits which are based on multi-element geochemistry and/or spectroscopy-based technologies, allowing for semi-quantitative to quantitative high-resolution modelling of key aspects of lithology, hydrothermal alteration, and mineralization. It will also offer insights to applications that may be cross-referenced to metallurgical test samples and therefore to geo-metallurgical properties of rocks and predictive modelling.

Chair:

Description: Increasing awareness and regulations on environmental impacts and mitigation in the mining industry, within the framework of sustainable mining, have placed important emphasis on the necessity of an integral understanding of chemical and physical stability of mine waste as well as the direct environmental impacts of mining operations. This thematic session will focus on the use of geochemistry applied to environmental studies that provide a deep understanding of the behaviour and impacts of mining waste products, and hence the necessary knowledge to determine efficient mitigation and control protocols. This session will include a specific special sub-session sponsored by the Unesco-IGCP682 project of mine tailing revalorization, focused on reprocessing of old and present tailing deposits for the recovery of elements / minerals of economic interest, within a framework of circular economy and sustainability. Studies on the applicability of environmental geochemistry to other impacts of the mining industry as well as other studies that provide useful applications to the mining industry are also welcomed.

Chair: Luciano Achurra, Amphos 21 Consulting Chile.

Description: Hydrogeochemical studies provide us with relevant information about water sources and the processes that affect them surficially and underground. The activities associated with the exploitation of metallic and non-metallic mineral deposits can cause changes in the chemistry of rivers and aquifers. Currently, the infiltration of water from tailings storage facilities and mitigation or remediation of sulphate or metals in aquifers is common. Related to this matter, concepts such as monitoring plans on water quality and mining closure plans, which involve a hydrogeochemical component, can condition the environmental approval of large projects. On the other hand, hydrochemical studies on brines, in the salt flats, are becoming increasingly important due to the growing demand of the lithium-associated energy industry, as well as the use of chemical and isotopic techniques in the exploration of deep geothermal systems. These topics and a general water scarcity have led to the current challenges which are focused on efficient water management and the protection of its chemical quality, which is closely related to its management. In the session, discussions related to these issues are welcome through presentations of applied hydrogeochemical techniques in water studies as well as the use of modelling tools which allow for a better understanding of the processes involved in the water cycle and their implications in the environment.

IAGS2022 dedicates this Technical Session to the Memory of our friend and colleague Dr. David Gray (1961 – 2019)

The exploration geochemical community recently lost one of its most energetic members, Dr David Gray. He died on November 21 in his home surrounded by his family following a battle with brain cancer.

David was a senior principal geochemist in CSIRO and one of the international leaders in exploration hydrogeochemistry.

David would be even more widely recognised had he not been such a selfless researcher. He always put the team, project and organisation before his own personal gain. David was a mentor for many, and he would engage with students and senior colleagues in the same manner; always constructive, supportive and considered. David formally supervised a number of students including three PhD students, not to mention the many more, like me, he unofficially mentored as undergrads, post grads or colleagues.

David was a Fellow of the AAG, a member and past President of the Australian Regolith Geoscientists Association and served on the Editorial Board for Geochemistry: Exploration, Environment, Analysis.

David’s early years were in Sydney, Australia, before moving to Perth with his job in CSIRO. He completed his B.Sc (Hons) in inorganic chemistry at the University of Sydney in 1982, before completing his Ph.D. in Soil Science from the same institution in 1986 researching the geochemistry of uranium and thorium during weathering. David joined CSIRO in 1987 where he remained until his early retirement due to failing health in 2017.

David led the establishment of hydrogeochemistry as an exploration tool that is now widely accepted and implemented by Australian State geological surveys and mineral explorers.

David remained an active Honorary Fellow of CSIRO. He was still passing on his ideas of simplifying exploration transition metal indices for groundwater by scaling with pH right up to the last weeks before his death. He was always positive. His quality of life had been good until his last few days which I would attribute to David’s personality. David’s optimism is something that those that went into the field with him would know all too well. He was always convinced you could collect another few samples even as darkness was descending, and he would literally bounce in and out of vehicles all day, every day, to ensure he got as much as possible done in the field.

His dedication to his science in the office was also admirable – he spent years trawling through pdf water reports and pulling out data, doing QAQC checks that has resulted in the Australian continental scale hydrogeochemistry data well summarised in this recent news article (https://www.csiro.au/en/Research/MRF/Areas/Resourceful-magazine/Issue-19/The-groundwater-explorer). The 320,000 quality groundwater data points are all thanks to David’s tenacious nature for collecting and curating results and being certain that “true backgrounds” and major element data would show patterns for application in mineral exploration and other fields if we just had enough samples (there was always more David would look for).

David was 58 and is survived by his wife, Celia, and children Ahren, Alex, Bec, Adam and Nathan.

As this is being written, I am taking a break from working on groundwater data, the interpretation of which is all based on the learnings I received from David over the last 15 years and his ongoing mentoring. I will raise a glass of wine (preferably David’s preferred sauvignon blanc) in his memory after I post this and continue to work on the data and further David’s legacy. I am forever grateful for David’s many years of mentorship and for hiring me in the first place. A terrific boss, teacher, scientist, colleague, and friend. He will be missed.

Ryan Noble

Chair: Verónica Oliveros, Universidad de Concepción.

Description: This session will deal with novel methodological approaches of isotopic geochemistry and geochronology in the fields of natural resources, environmental geology and earth dynamics. Examples of systematics studies and sampling protocols aiming at the discovery of new ore deposits, geochemical anthropic anomalies, paleoclimatic trends or processes and natural risk assessment are welcomed. Applications of new isotopic tools and geochronometers in the Earth Sciences will be also of interest in this session.

Chair: Pamela Castillo, Universidad de Concepción.

Description: Climate, soil and agricultural management are the main factors that impact yield and grape quality. Geologic studies are important in viticulture since the physical and chemical properties of soils are strongly influenced by lithological, geochemical, and structural characteristics of the soil parent materials. This thematic session welcomes contributions that link diverse areas of geosciences (geology, geochemistry, geomorphology, geophysics, mineralogy, soil sciences, hydrogeology, hydrology, climatology, biogeochemistry, etc.) that influence aspects such as viticultural potential and wine quality, the terroir concept, soil-plant interactions, root system development, water availability, the characterization of viticultural valleys, exploration of new areas apt for viticulture, environmental issues, challenges and impacts of climate change, standardization of methodologies, and technological solutions, among others.

Chair: Cliff Stanley, Acadia University.

Description: Appropriate sampling, sample preparation, analysis, and data quality assessment and control procedures are essential for the proper exploration, evaluation, and exploitation of mineral deposits as well as for environmental assessments, remediation, monitoring, and related applied research designed to improve these activities. This session invites contributions addressing two themes: (i) presentations that improve our understanding of QAQC procedures, that expand/improve the application of QAQC procedures, or illustrate interesting successes or failures in quality control and (ii) presentations that illustrate new analytical technologies or applications that can be used to improve the practice of exploration or environmental geochemistry. Presentations accepted for this session will not involve the use of technologies that remain secret or proprietary; as such procedures cannot be fully evaluated in a scientific manner, preventing an objective assessment of their value and use in exploration and environmental geochemistry applications.