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2. International Union of Geological Sciences Manual of Standard Methods for Establishing the Global Geochemical Reference Network

Author

Demetriades, Alecos, Johnson, Christoper C., Smith, David B., Ladenberger, Anna, Adánez Sanjuan, Paula, Argyraki, Ariadne, Stouraiti, Christina, Caritat, Patrice de, Knights, Kate V., Prieto Rincón, Gloria, and Simubali, Gloria Namwi

Subjects
baseline studies, sampling, data conditioning, geochemical surveys, sample preparation, stream water, rock, stream sediment, humus, floodplain sediment, reference materials, project management, analytical methods, sample storage, map production, data management, quality control, overbank sediment, residual soil
Abstract

Source web page: https://www.globalgeochemicalbaselines.eu/content/174/iugs-manual-of-standard-methods-for-establishing-the-global-geochemical-reference-network-/ SYNOPSIS “Everything in and on the Earth - mineral, animal and vegetable - is made from one, or generally some combination of, the natural chemical elements occurring in the rocks of the Earth’s crust and the surficial materials derived from them. Everything that is grown, or made, depends upon the availability of the appropriate elements. The existence, quality and survival of life depends upon the availability of elements in the correct proportions and combinations. Because natural processes and human activities are continuously modifying the chemical composition of our environment, it is important to determine the present abundance and spatial distribution of the elements across the Earth’s surface in a much more systematic manner than has been attempted hitherto” (Darnley et al., 1995, p.x). Although such a global database is urgently needed for multi-purpose use, the systematic attempt is still in its infancy because of the non-existence of a manual of comprehensive and standardised methods of sampling and other supporting procedures. The current ‘International Union of Geological Sciences Manual of Standard Methods for Establishing the Global Geochemical Reference Network’ fills this gap. The Manual follows the concept of 7356 Global Terrestrial Network grid cells of 160x160 km, covering the land surface of Earth, with five random sites within each grid cell for the collection of samples. This allows the establishment of the standardised Global Geochemical Reference Network with respect to rock, residual soil, humus, overbank sediment, stream water, stream sediment and floodplain sediment. Apart from the instructions for the collection of samples, the Manual covers sample preparation and storage, development of reference materials, geoanalytical methods, quality control procedures, geodetic and parametric levelling of existing geochemical data sets, data conditioning for the generation of time-independent geochemical data, management of data and map production, and finally project management. This Manual presents, for the first time a comprehensive overview of the standardised methods that should be employed across the land surface of the Earth to map the distribution of chemical elements in rock, soil, sediment and water. The methods described herein, apart from their use for Establishing the Global Geochemical Reference Network, can be used in other geochemical surveys at any mapping scale. The URL of the pdf file is: https://www.globalgeochemicalbaselines.eu/datafiles/file/IUGS-CGGB_2022_Manual_of_Standard_Methods_for_Establishing_the_GGRN.pdf IUGS APPROVAL FOR PUBLICATION The Executive Committee of the International Union of Geological Sciences at its 77th meeting in Paris (16-18 March 2022), unanimously approved the “International Union of Geological Sciences Manual of Standard Methods for Establishing the Global Geochemical Reference Network” to be published as a formal IUGS Publication for its 60th Anniversary celebration. The IUGS Executive Committee members John Ludden (President), Hassina Mouri (Vice President), Daekyo Cheong (Vice President), Stanley C. Finney (Secretary-General), Hiroshi Kitazato (Treasurer), Qiuming Cheng (Past President), Silvia Peppoloni (Councillor), Claudia Inés Mora (Councillor), Jennifer McKinley (Councillor), and Ludwig Stroink (Councillor) are thanked for approving the publication of this Manual. Supplementary material The supplementary material provided in different Chapters and Annexes is very important and should be consulted: Chapter 2 Supplementary material Chapter 2 Annexe A2.1 Supplementary material Chapter 3.2 Annexe A3.2.1 Supplementary material Chapter 7 Supplementary material Chapter 8 Supplementary material An innovation for this freely available publication is the provision of the original MicrosoftTM Word files, Original figures, and PowerPoint presentations with embedded figures: Chapter files: Word text; Original figures; PowerPoint presentations, CITATION: Demetriades, A., Johnson, C.C., Smith, D.B., Ladenberger, A., Adánez Sanjuan, P., Argyraki, A., Stouraiti, C., Caritat, P. de, Knights, K.V., Prieto Rincón, G. & Simubali, G.N. (Editors), 2022. International Union of Geological Sciences Manual of Standard Methods for Establishing the Global Geochemical Reference Network. IUGS Commission on Global Geochemical Baselines, Athens, Hellenic Republic, Special Publication, 2, 515 pp.; https://doi.org/10.5281/zenodo.7307696.

Published
2022
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4. The Heavy Mineral Map of Australia: Vision and Pilot Project

Author

Caritat, Patrice De, McInnes, Brent I. A., Walker, Alexander T., Bastrakov, Evgeniy, Rowins, Stephen M., and Prent, Alexander M.

Subjects
geochemistry_petrology
Abstract

We describe a vision for a national-scale heavy mineral (HM) map generated through automated mineralogical identification and quantification of HMs contained in floodplain sediments from large catchments covering most of Australia. The composition of the sediments reflects the dominant rock types in each catchment, with the generally resistant HMs largely preserving the mineralogical fingerprint of their host protoliths through the weathering-transport-deposition cycle. Heavy mineral presence/absence, absolute and relative abundance, and co-occurrence are metrics useful to map, discover and interpret catchment lithotype(s), geodynamic setting, magmatism, metamorphic grade, alteration or mineralization. Underpinning this vision is a pilot project, focusing on a subset of the national sediment sample archive, which is used to demonstrate the feasibility of the larger, national-scale project. We preview a bespoke, cloud-based mineral network analysis (MNA) tool to visualize, explore and discover relationships between HMs as well as between them and geological setting or mineral deposits. We envisage that the Heavy Mineral Map of Australia and MNA tool will contribute significantly to mineral prospectivity analysis and modeling here, particularly for technology critical elements and their host minerals, which are central to the global economy transitioning to a more sustainable, decarbonized paradigm.

Published
2022

6. Impacts of airborne contamination on regional soil and water quality: the Kola Peninsula, Russia

Author

Reimann, Clemens, Banks, David, and Caritat, Patrice De

Subjects
Sulfur industry -- Research, Environmental issues, Science and technology
Abstract

Researchers from the Geological Survey of Norway revealed in a study that emissions of sulfur dioxide from various industries such as nickel, smelters, roasting plant, and refinery on the Kola Peninsula, Russia, do not lead to the acidification of soil humus, mineral soil, or lake water within the area.

Published
2000

7. Tertiary volcanic rocks and the potassium content of Gulf Coast shales - the smoking gun

Author

Bloch, John, Hutcheon, Ian E., and Caritat, Patrice de

Subjects
Gulf Coast (United States) -- Natural history, Shale -- Research, Rocks, Igneous -- Research, Geology, Stratigraphic -- Tertiary, Earth sciences
Abstract

The majority of Tertiary volcanic rocks of the western United States and Mexico are alkaline in composition and may contain as much as 50 wt% equivalent K-feldspar. Emplacement of these volcanic strata is coeval with Tertiary shale deposition in the Texas Gulf Coast, and they previously have been identified as likely sources of sediment for Gulf Coast shales. Evaluation of chemical trends in Gulf Coast shales, particularly [K.sub.2]O, indicates changes in sediment composition in the lower Eocene, Oligocene, and near the Oligocene-Miocene boundary. In particular, there is a 250% increase in [K.sub.2]O content from [approximately]2 wt% to [approximately]5 wt% from the late Eocene to the early Oligocene. Gulf Coast shale bulk-rock compositions arc consistent with a Tertiary volcanic source. Estimates of erosion and mass balance calculations suggest that in the south Texas Gulf Coast, the Oligocene Frio Formation may contain between 60% and 85% volcanic detritus, and coeval Frio shales to the north contain [approximately]25%. Vertical and lateral compositional variations highlight variable abundances of source detritus and the effects of weathering and depositional processes on Gulf Coast shale composition. Trends of increasing [K.sub.2]O content with depth in Gulf Coast shales previously have been interpreted to result from open-system diagenesis and K-metasomatism at depth. The data presented herein suggest instead that these trends result from variable provenance and the influx of large volumes of Tertiary alkaline volcanic material. Therefore, diagenetic models that invoke a homogeneous initial shale composition and open-system behavior may be invalid.

Published
1998

8. Silica activity and the smectite-illite reaction

Author

Abercrombie, Hugh J., Hutcheon, Ian E., Bloch, John D., and Caritat, Patrice de

Subjects
Diagenesis -- Research, Geology, Structural -- Research, Smectite -- Research, Silicates -- Research, Earth sciences
Abstract

Early silicate diagenesis is characterized by the precipitation of minerals with high silica activity, such as opaline silica, smectite, and clinoptilolite, and by pore-water silica activities exceeding quartz saturation. With burial, this early, high-silica activity diagenetic facies is succeeded by a low-silica activity facies distinguished by quartz precipitation and progressive development of illite as the nonexpandable component of mixed-layer clays. We suggest that the smectite-illite reaction occurs as a consequence of the reduction of silica activity at the onset of quartz precipitation. Data from oceanic and sedimentary basins confirm that the smectite-illite reaction does not control aqueous silica activities. Where the smectite-illite reaction occurs at higher temperatures, aqueous silica activities likewise reach quartz saturation at higher temperatures.

Published
1994

9. Tertiary volcanic rocks and the potassium content of Gulf Coast shales-the smoking gun: comment and reply

Author

Lynch, F. Leo, Milliken, Kitty L., Awwiller, David N., Mack, Larry E., Bloch, John, Hutcheon, Ian E., and Caritat, Patrice de

Subjects
Gulf of Mexico -- Natural history, Frio County, Texas -- Natural history, Shale -- Research, Rocks, Sedimentary -- Composition, Potassium -- Analysis, Earth sciences
Abstract

The high potassium (K) content of shales derived from the Gulf Coast of Mexico and Texas may be accounted for various provenance changes among volcanic rocks. Geochemical and geochronoligical data show that the area is marked by increased depositional K sources, thereby increasing the possibility of a diagenesis. This assumption, however, is refutable since it is based merely on a two-component mixing model, which is insufficient in gathering adequate evidences for a provenance change within the Wilcox formation.

Published
1999

13. Surficial and Deep Earth Material Prediction from Geochemical Compositions.

Author

Talebi, Hassan, Mueller, Ute, Tolosana-Delgado, Raimon, Grunsky, Eric C., McKinley, Jennifer M., and Caritat, Patrice de

Subjects
GEOCHEMICAL surveys, ANALYTICAL geochemistry, PREDICTION models, RESEARCH methodology, SIMULATION methods & models, REGOLITH
Abstract

Prediction of true classes of surficial and deep earth materials using multivariate spatial data is a common challenge for geoscience modelers. Most geological processes leave a footprint that can be explored by geochemical data analysis. These footprints are normally complex statistical and spatial patterns buried deep in the high-dimensional compositional space. This paper proposes a spatial predictive model for classification of surficial and deep earth materials derived from the geochemical composition of surface regolith. The model is based on a combination of geostatistical simulation and machine learning approaches. A random forest predictive model is trained, and features are ranked based on their contribution to the predictive model. To generate potential and uncertainty maps, compositional data are simulated at unsampled locations via a chain of transformations (isometric log-ratio transformation followed by the flow anamorphosis) and geostatistical simulation. The simulated results are subsequently back-transformed to the original compositional space. The trained predictive model is used to estimate the probability of classes for simulated compositions. The proposed approach is illustrated through two case studies. In the first case study, the major crustal blocks of the Australian continent are predicted from the surface regolith geochemistry of the National Geochemical Survey of Australia project. The aim of the second case study is to discover the superficial deposits (peat) from the regional-scale soil geochemical data of the Tellus Project. The accuracy of the results in these two case studies confirms the usefulness of the proposed method for geological class prediction and geological process discovery. [ABSTRACT FROM AUTHOR]

Published
2019
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15. Comparing results from two continental geochemical surveys to world soil composition and deriving Predicted Empirical Global Soil (PEGS2) reference values

Author

Caritat, Patrice de, Reimann, Clemens, NGSA Project Team, GEMAS Project Team, Bel-Lan Ballester, Alejandro, Locutura Rupérez, Juan, Caritat, Patrice de, Reimann, Clemens, NGSA Project Team, GEMAS Project Team, Bel-Lan Ballester, Alejandro, and Locutura Rupérez, Juan

Abstract

Analytical data for 10 major oxides (Al2O3, CaO, Fe2O3, K2O, MgO, MnO, Na2O, P2O5, SiO2 and TiO2), 16 total trace elements (As, Ba, Ce, Co, Cr, Ga, Nb, Ni, Pb, Rb, Sr, Th, V, Y, Zn and Zr), 14 aqua regia extracted elements (Ag, As, Bi, Cd, Ce, Co, Cs, Cu, Fe, La, Li, Mn, Mo and Pb), Loss On Ignition (LOI) and pH from 3526 soil samples from two continents (Australia and Europe) are presented and compared to (1) the composition of the upper continental crust, (2) published world soil average values, and (3) data from other continental-scale soil surveys. It can be demonstrated that average upper continental crust values do not provide reliable estimates for natural concentrations of elements in soils. For many elements there exist substantial differences between published world soil averages and the median concentrations observed on two continents. Direct comparison with other continental datasets is hampered by the fact that often mean, instead of the statistically more robust median, is reported. Using a database of the worldwide distribution of lithological units, it can be demonstrated that lithology is a poor predictor of soil chemistry. Climate-related processes such as glaciation and weathering are strong modifiers of the geochemical signature inherited from bedrock during pedogenesis. To overcome existing shortcomings of predicted global or world soil geochemical reference values, we propose Preliminary Empirical Global Soil reference values based on analytical results of a representative number of soil samples from two continents (PEGS2).

Published
2012

16. New soil composition data for Europe and Australia: demonstrating comparability, identifying continental-scale processes and learning lessons for global geochemical mapping

Author

Reimann, Clemens, Caritat, Patrice de, GEMAS Project Team, NGSA Project Team, Locutura Rupérez, Juan, Reimann, Clemens, Caritat, Patrice de, GEMAS Project Team, NGSA Project Team, and Locutura Rupérez, Juan

Abstract

New geochemical data from two continental-scale soil surveys in Europe and Australia are compared. Internal project standards were exchanged to assess comparability of analytical results. The total concentration of 26 oxides/elements (Al2O3, As, Ba, CaO, Ce, Co, Cr, Fe2O3, Ga, K2O, MgO, MnO, Na2O, Nb, Ni, P2O5, Pb, Rb, SiO2, Sr, Th, TiO2, V, Y, Zn, and Zr), Loss On Ignition (LOI) and pH are demonstrated to be comparable. Additionally, directly comparable data for 14 elements in an aqua regia extraction (Ag, As, Bi, Cd, Ce, Co, Cs, Cu, Fe, La, Li, Mn, Mo, and Pb) are provided for both continents. Median soil compositions are close, though generally Australian soils are depleted in all elements with the exception of SiO2 and Zr. This is interpreted to reflect the generally longer and, in places, more intense weathering in Australia. Calculation of the Chemical Index of Alteration (CIA) gives a median value of 72% for Australia compared to 60% for Europe. Element concentrations vary over 3 (and up to 5) orders of magnitude. Several elements (total As and Ni; aqua regia As, Co, Bi, Li, Pb) have a lower element concentration by a factor of 2–3 in the soils of northern Europe compared to southern Europe. The break in concentration coincides with the maximum extent of the last glaciation. The younger soils of northern Europe are more similar to the Australian soils than the older soils from southern Europe. In Australia, the central region with especially high SiO2 concentrations is commonly depleted in many elements. The new data define the natural background variation for two continents on both hemispheres based on real data. Judging from the experience of these two continental surveys, it can be concluded that analytical quality is the key requirement for the success of global geochemical mapping

Published
2011

20. Safe storage and effective monitoring of CO2 in depleted gas fields.

Author

Jenkins, Charles R., Cook, Peter J., Ennis-King, Jonathan, Undershultz, James, Boreham, Chris, Dance, Tess, Caritat, Patrice de, Etheridge, David M., Freifeld, Barry M., Hortle, Allison, Kirste, Dirk, Paterson, Lincoln, Pevzner, Roman, Schacht, Ulrike, Sharma, Sandeep, Stalker, Linda, and Urosevic, Milovan

Subjects
CARBON sequestration, GAS fields, RISK assessment, CARBON
Abstract

The article offers information on the Otway Project, located in Victoria in Australia. It mentions how the said project provides demonstrations on large-scale carbon capture and storage (CCS) in depleted gas field. Moreover, it features how public consent and risk assessment affects the demonstration of carbon storages.

Published
2012
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