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During recent decades, argillaceous sedimentary formations have been studied as potential host formations for the geological disposal of long-living and heat-emitting radioactive waste—Boom Clay in Belgium and Opalinus Clay and Brown Dogger in Switzerland. A significant issue in the long-term performance of these potential host rocks concerns the generation and transport of gases. The pressure resulting from the generation of gas in an almost impermeable geological medium in the near field of a repository will increase. Under high gas pressures, the mechanical and hydraulic properties of the host rock are expected to change significantly. Preferential gas pathways may develop which exploit material heterogeneity, anisotropy (bedding planes), rock discontinuities, or interfaces between the different components of the repository, and may eventu- ally lead to the release of the produced gases. Gas flow through these clayey rocks is investigated on the basis of laboratory work. Priority has been given to studying the volume change response of these initially water-saturated materials through relatively fast and controlled volume-rate gas injections. The effect of the gas injection rate, the confining pressure and the bedding orientation on the gas transport properties have been studied with particular attention paid to the coupling with strain behaviour. The results have shown features common to the three formations concerning the gas transfer process through preferential pathways, despite their initially differential properties., Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work is funded by the European Joint Programme on Radioactive Waste Management (EURAD WP-GAS) within the Horizon 2020-Euratom programme under grant agreement No 847593 (2019–2024). Past research contracts with NAGRA (National Cooperative for the Disposal of Radioactive Waste, Switzerland) and ONDRAF/NIRAS (Belgian Agency for Radioactive Waste and Enriched Fissile Materials) also provided funding., Peer Reviewed, Postprint (published version)

Um Taghir area is restricted along a shear zone of the Qena-Safaga road, actually it belongs to the Central Eastern Desert that represents one of the most important occurrences of radioactive elements in Egypt. The current study aims to calculate the content of the radioactive elements of the investigated granitic rocks by radiative methods for the geochemical analyses, are determined by (X-ray fluorescence (XRF) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The average concentrations values of 226Ra, 232 Th are lower than that of world's average and the average activities in Egyptian soil. While in 40K series is higher than that of world's average and the average activities in Egyptian soil. The range of measured activities differed widely as their presence in rocks samples depends on their physical, chemical and geo-chemical properties and the pertinent environment. © Published under licence by IOP Publishing Ltd.

Calcite veins precipitated in the Estamariu thrust during two tectonic events are studied in order to (i) decipher the temporal and spatial relationships between deformation and fluid migration in a long-lived thrust and (ii) determine the influence of basement rocks on the fluid chemistry during deformation. Structural and petrological observations constrain the relative timing of fluid migration and vein formation, whilst geochemical analyses (13C, 18O, 87Sr=86Sr, clumped isotope thermometry, and elemental composition) applied to the related calcite cements and host rocks indicate the fluid origin, pathways, and extent of fluid rock interaction. The first tectonic event, recorded by calcite cements Cc1a and Cc2, is attributed to the Alpine reactivation of the Estamariu thrust. Analytical data indicate that these cements precipitated from heated meteoric fluids (temperatures in the range of 50 to 100 C) that had interacted with basement rocks (87Sr=86Sr 0.71) before upflowing through the thrust zone. The second tectonic event, attributed to the Neogene extension, is characterized by the reactivation of the Estamariu thrust and the formation of normal faults and shear fractures sealed by calcite cements Cc3, Cc4, and Cc5. Analytical data indicate that cements Cc3 and Cc4 precipitated from hydrothermal fluids (temperatures between 130 and 210 C and between 100 and 170 C, respectively) that had interacted with basement rocks (87Sr=86Sr 0.71) and been expelled through fault zones during deformation. In contrast, cement Cc5 probably precipitated from meteoric waters that likely percolated from the surface through small shear fractures. The comparison between our results and already published data in other structures from the southern Pyrenees suggests that regardless of the origin of the fluids and the tectonic context, basement rocks have a significant influence on the fluid chemistry, particularly on the 87Sr=86Sr ratio. Accordingly, the cements precipitated from flui

The study of the relationships between two compositions is of paramount importance in geochemical data analysis. This paper develops a compositional version of canonical correlation analysis, called CoDA-CCO, for this purpose. We consider two approaches, using the centred log-ratio transformation and the calculation of all possible pairwise log-ratios within sets. The relationships between both approaches are pointed out, and their merits are discussed. The related covariance matrices are structurally singular, and this is efficiently dealt with by using generalized inverses. We develop compositional canonical biplots and detail their properties. The canonical biplots are shown to be powerful tools for discovering the most salient relationships between two compositions. Some guidelines for compositional canonical biplots construction are discussed. A geochemical data set with X-ray fluorescence spectrometry measurements on major oxides and trace elements of European floodplains is used to illustrate the proposed method. The relationships between an analysis based on centred log-ratios and on isometric log-ratios are also shown., Peer Reviewed, Postprint (author's final draft)

© The Author(s), 2015. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in GeoResJ 6 (2015): 108-114, doi:10.1016/j.grj.2015.02.012., Over the course of a scientific career, a large fraction of the data collected by scientific investigators turns into data at risk of becoming inaccessible to future science. Although a part of the investigators’ data is made available in manuscripts and databases, other data may remain unpublished, non-digital, on degrading or near obsolete digital media, or inadequately documented for reuse. In 2013, Integrated Earth Data Applications (IEDA) provided data rescue mini-awards to three Earth science investigators. IEDA’s user communities in geochemistry, petrology, geochronology, and marine geophysics collect long-tail data, defined as data produced by individuals and small teams for specific projects, tending to be of small volume and initially for use only by these teams, thus being less likely to be easily transferred or reused. Long-tail data are at greater risk of omission from the scientific record. The awarded projects topics were (1) Geochemical and Geochronological data on volcanic rocks from the Fiji, Izu-Bonin-Mariana arc, and Endeavor segments of the global mid-ocean ridge, (2) High-Resolution, Near-bottom Magnetic Field Data, and (3) Geochemistry of Lunar Glasses. IEDA worked closely with the awardees to create a plan for the data rescue, resulting in the registration of hundreds of samples and the entry of dozens of data and documentation files into IEDA data systems. The data were made openly accessible and citable by assigning persistent identifiers for samples and files. The mini-award program proved that a relatively small incentive combined with data facility guidance can motivate investigators to accomplish significant data rescue., This work was funded by the IEDA cooperative agreement, U.S. NSF Award0950477.

Over the course of a scientific career, a large fraction of the data collected by scientific investigators turns into data at risk of becoming inaccessible to future science. Although a part of the investigators’ data is made available in manuscripts and databases, other data may remain unpublished, non-digital, on degrading or near obsolete digital media, or inadequately documented for reuse. In 2013, Integrated Earth Data Applications (IEDA) provided data rescue mini-awards to three Earth science investigators. IEDA’s user communities in geochemistry, petrology, geochronology, and marine geophysics collect long-tail data, defined as data produced by individuals and small teams for specific projects, tending to be of small volume and initially for use only by these teams, thus being less likely to be easily transferred or reused. Long-tail data are at greater risk of omission from the scientific record. The awarded projects topics were (1) Geochemical and Geochronological data on volcanic rocks from the Fiji, Izu-Bonin-Mariana arc, and Endeavor segments of the global mid-ocean ridge, (2) High-Resolution, Near-bottom Magnetic Field Data, and (3) Geochemistry of Lunar Glasses. IEDA worked closely with the awardees to create a plan for the data rescue, resulting in the registration of hundreds of samples and the entry of dozens of data and documentation files into IEDA data systems. The data were made openly accessible and citable by assigning persistent identifiers for samples and files. The mini-award program proved that a relatively small incentive combined with data facility guidance can motivate investigators to accomplish significant data rescue.

In 1936 Ida Noddack published her landmark paper “Über die Allgegenwart der chemischen Elemente” – in English „About Universal presence of Elements“ (Noddack, 1936). In this article she states: “Alle chemischen Elemente kommen in allen Mineralien vor.“ – in English: „All chemical elements are present in all minerals.” This conclusion was based in the painstaking trace element analysis of bulk minerals. She was able to document the presence of such chemical elements as Re in sphalerite down to 10 ppb (Noddack, 1936). It was, of course impossible for her to anticipate the development of modern microanalytical instrumentation, which is able to operate routinely at the picogram test portion range. The Helmholtz- Institute Freiberg for Resource Technology is currently working to establish the Super-SIMS method (Döbeli et al, 1994) for analysis of minerals, ores and other materials related to resource technology. The extreme sensitivity of this technique raises the question of the validity of the concept of Universal Presence of Elements. It is expected that the Super-SIMS we will be able to quantify some elements down to the 1 ng/g level (10-12 atoms/atoms) in ideal matrices. Using a commercial available ion probe we will be able to focus the ion beam down to 2 µm in diameter, equivalent to a sampling mass at or below the sub-ng level. Simulations of the probabilities of finding elements of interest at such low target concentrations show that the Super-SIMS will reach the point that the chance of measuring these elements in such small sampling volumes will be less than 10 %.This leads to a number of new questions which need to be addressed when addressing the topic of a given element yes-or-no. Is the amount of an ultratrace element in a mineral determined by the concentration in the bulk mineral or by the analytical capabilities? Is it still possible to describe the geochemical behavior of ultratrace elements if the probability of detection of such elements in very tiny

In 1936 Ida Noddack published her landmark paper “Über die Allgegenwart der chemischen Elemente” – in English „About Universal presence of Elements“ (Noddack, 1936). In this article she states: “Alle chemischen Elemente kommen in allen Mineralien vor.“ – in English: „All chemical elements are present in all minerals.” This conclusion was based in the painstaking trace element analysis of bulk minerals. She was able to document the presence of such chemical elements as Re in sphalerite down to 10 ppb (Noddack, 1936). It was, of course impossible for her to anticipate the development of modern microanalytical instrumentation, which is able to operate routinely at the picogram test portion range. The Helmholtz- Institute Freiberg for Resource Technology is currently working to establish the Super-SIMS method (Döbeli et al, 1994) for analysis of minerals, ores and other materials related to resource technology. The extreme sensitivity of this technique raises the question of the validity of the concept of Universal Presence of Elements. It is expected that the Super-SIMS we will be able to quantify some elements down to the 1 ng/g level (10-12 atoms/atoms) in ideal matrices. Using a commercial available ion probe we will be able to focus the ion beam down to 2 µm in diameter, equivalent to a sampling mass at or below the sub-ng level. Simulations of the probabilities of finding elements of interest at such low target concentrations show that the Super-SIMS will reach the point that the chance of measuring these elements in such small sampling volumes will be less than 10 %.This leads to a number of new questions which need to be addressed when addressing the topic of a given element yes-or-no. Is the amount of an ultratrace element in a mineral determined by the concentration in the bulk mineral or by the analytical capabilities? Is it still possible to describe the geochemical behavior of ultratrace elements if the probability of detection of such elements in very tiny

Production of natural gas from shale reservoirs in the lower 48 states has increased exponentially from about 100 million cubic feet of gas per day (MMcf/d) in 1997 to more than 5500 MMcf/d in 2008 (Brathwaite, 2009). This increase is part of a trend of increased natural gas production from all unconventional reservoirs, coincidental with a linear decline in production from conventional onshore reservoirs (Deo, 2009). Projections of these trends indicate that by 2025 gas production from onshore unconventional reservoirs will surpass the combined production from onshore conventional, offshore, and Alaskan reservoirs (Deo, 2009). Among the unconventional resources are 7 trillion cubic feet of gas in the Mancos/Mowry petroleum system of the Uinta and Piceance Basins in Utah and Colorado (U.S. Geological Survey, Uinta-Piceance Assessment Team, 2003). Exploitation of this resource has increased dramatically in recent decades as the number of gas wells drilled since 1980 in the Uinta and Piceance basins more than quadrupled the total that had been drilled before 1980 (Deo, 2009). The Mancos Shale is the second largest shale gas producer in the Rocky Mountains, exceeded only by the Bakken Shale of the Williston Basin (Brathwaite, 2009). Mancos production, however, peaked in the first quarter of 2003 at 44.8 MMcf/d, and by the second quarter of 2008 had declined to 32 MMcf/d (Brathwaite, 2009). As some wells produce from depths greater than 13,000 feet, Mancos Shale exploration can require considerable financial risk. Reducing that risk, particularly for independent operators, by providing the industry with an integrated compilation of geologic and engineering data relevant for assessing an exploration/production program, is the main objective of this project. Curtis and others (2008) defined eight parameters that need to be evaluated for a successful shale-gas play: 1) total organic carbon (TOC), 2) maturation, 3) gas-in-place, 4) permeability, 5) pore pressure, 6) brittle

Production of natural gas from shale reservoirs in the lower 48 states has increased exponentially from about 100 million cubic feet of gas per day (MMcf/d) in 1997 to more than 5500 MMcf/d in 2008 (Brathwaite, 2009). This increase is part of a trend of increased natural gas production from all unconventional reservoirs, coincidental with a linear decline in production from conventional onshore reservoirs (Deo, 2009). Projections of these trends indicate that by 2025 gas production from onshore unconventional reservoirs will surpass the combined production from onshore conventional, offshore, and Alaskan reservoirs (Deo, 2009). Among the unconventional resources are 7 trillion cubic feet of gas in the Mancos/Mowry petroleum system of the Uinta and Piceance Basins in Utah and Colorado (U.S. Geological Survey, Uinta-Piceance Assessment Team, 2003). Exploitation of this resource has increased dramatically in recent decades as the number of gas wells drilled since 1980 in the Uinta and Piceance basins more than quadrupled the total that had been drilled before 1980 (Deo, 2009). The Mancos Shale is the second largest shale gas producer in the Rocky Mountains, exceeded only by the Bakken Shale of the Williston Basin (Brathwaite, 2009). Mancos production, however, peaked in the first quarter of 2003 at 44.8 MMcf/d, and by the second quarter of 2008 had declined to 32 MMcf/d (Brathwaite, 2009). As some wells produce from depths greater than 13,000 feet, Mancos Shale exploration can require considerable financial risk. Reducing that risk, particularly for independent operators, by providing the industry with an integrated compilation of geologic and engineering data relevant for assessing an exploration/production program, is the main objective of this project. Curtis and others (2008) defined eight parameters that need to be evaluated for a successful shale-gas play: 1) total organic carbon (TOC), 2) maturation, 3) gas-in-place, 4) permeability, 5) pore pressure, 6) brittle

The correct analysis of amorphous silica concentration (CASi) in natural waters is crucial if one wants to correctly quantify terrestrial and/or riverine ASi fluxes. Soil ASi measurements are conducted with a constant solid to solution ratio (). As the suspended particulate matter concentration (CSPM), and therefore, cannot be exactly known a priori in river samples. It is important to understand how variations in effect analysed CASi. The objectives of this paper are (i) to investigate whether and how variations in values affect measured CASi in river runoff samples and (ii) to investigate whether or not it is possible to define a range of within which CASi in runoff and/or soil samples can be accurately measured. For the laboratory experiment 30 runoff samples with a wide range of CSPM, typical for the Belgian Loam Belt, were prepared and analysed using the alkaline digestion method (0.1M Na2CO3). Our study confirmed that the alkaline digestion method proposed by DeMaster can be used for runoff samples provided that is within certain limits: at very low (<0.1kgm-3), subsample heterogeneity results in high variability of measured CASi while at higher values (>0.8kgm-3) incomplete dissolution of ASi as well as the reduction of mineral dissolution rates results in underestimated CASi. As both errors compensate one another, the range of applicable -values can be extended above the theoretically correct limit (1.6kgm-3). The finding that reliable measurements can be made within a relatively wide range of values (0.1≤≤1.6kgm-3) is important. It is now possible to propose a method for the measurement of ASi in runoff samples. We make recommendations for ASi analysis distinguishing samples with a low and high CSPM. For samples with a low CSPM (≤1.6kgm-3) the standard procedure is proposed while for samples with a high CSPM (>1.6kgm-3) an adapted procedure is proposed, analogue to that for soil samples. However, one should be aware that the range and limits for pr

The correct analysis of amorphous silica concentration (CASi) in natural waters is crucial if one wants to correctly quantify terrestrial and/or riverine ASi fluxes. Soil ASi measurements are conducted with a constant solid to solution ratio (). As the suspended particulate matter concentration (CSPM), and therefore, cannot be exactly known a priori in river samples. It is important to understand how variations in effect analysed CASi. The objectives of this paper are (i) to investigate whether and how variations in values affect measured CASi in river runoff samples and (ii) to investigate whether or not it is possible to define a range of within which CASi in runoff and/or soil samples can be accurately measured. For the laboratory experiment 30 runoff samples with a wide range of CSPM, typical for the Belgian Loam Belt, were prepared and analysed using the alkaline digestion method (0.1M Na2CO3). Our study confirmed that the alkaline digestion method proposed by DeMaster can be used for runoff samples provided that is within certain limits: at very low (<0.1kgm-3), subsample heterogeneity results in high variability of measured CASi while at higher values (>0.8kgm-3) incomplete dissolution of ASi as well as the reduction of mineral dissolution rates results in underestimated CASi. As both errors compensate one another, the range of applicable -values can be extended above the theoretically correct limit (1.6kgm-3). The finding that reliable measurements can be made within a relatively wide range of values (0.1≤≤1.6kgm-3) is important. It is now possible to propose a method for the measurement of ASi in runoff samples. We make recommendations for ASi analysis distinguishing samples with a low and high CSPM. For samples with a low CSPM (≤1.6kgm-3) the standard procedure is proposed while for samples with a high CSPM (>1.6kgm-3) an adapted procedure is proposed, analogue to that for soil samples. However, one should be aware that the range and limits for pr

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1982., MICROFICHE COPY AVAILABLE IN ARCHIVES AND LINDGREN, Bibliography: leaves 209-226., by Harlan Wheelock Stockman., Ph.D.

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1982., MICROFICHE COPY AVAILABLE IN ARCHIVES AND LINDGREN, Bibliography: leaves 209-226., by Harlan Wheelock Stockman., Ph.D.

The natural variation in heavy metal contents of subsurface sediments in the southern Netherlands is described, based on a series of 820 bulk geochemical analyses. The detrital heavy metal contents of these sediments show linear correlations with Al as a result of their joint occurrence in phyllosilicates. Anomalous enrichments occur as a result of the presence of glauconite (As, Cr, Ni, Pb, Zn), pyrite (As) or Fe-oxides (As, Ba, Ni, Zn), due to the interaction of organic-rich subsurface material with groundwater (Co, Ni, Zn) or as a result of anthropogenic pollution in topsoils (Cu, Pb, Zn). The contents of Al, Fe, K and S are well suited to determine background values, and to identify the cause for anomalous accumulations of heavy metals. © 1997 Elsevier Science B.V.

Mueller, U. A., & Grunsky, E. C. (2016). Multivariate spatial analysis of lake sediment geochemical data; Melville Peninsula, Nunavut, Canada. Applied Geochemistry. Available here.