Analytical Geochemistry Research Articles

Petroleum Potential Prospectivity of Muglad Basin, South Sudan: A Case of Source Rocks Characterisation in the Drilled Kaikang West-1 Well

This study focuses on Prospectivity of Petroleum Potential of Muglad basin, South Sudan, with the help of petroleum source rocks characterisation in the drilled Kaikang West-1 Well based on the organic matter quantity, quality, and the thermal maturation generation capability of the organic matter disseminated in the analysed rock samples. Muglad basin is a major petroliferous Western and Central African Rifts System (WCARS) member, with estimated reserves of 2,053 mm bbl. Muglad Basin comprises thick sandstones of Aradeiba and Bentiu Formations, considered to be the main petroleum prospectivity targets, with trapping mechanism being structural faults and lithological anticlines. The organic matter contents were determined directly from laboratory analyses of the source rock samples with the help of seismic and gamma ray profiles, total organic carbon (TOC wt %), maturity indices (OI, HI and PI), temperature maximum (Tmax °C), porosities and other sedimentological parameters. This study involved a series of analytical geochemistry and petro-physical studies to ascertain a number of effective source rock samples from the well cores which were then analysed in terms of TOC, OI, PI, HI, S2, S1 and Tmax to determine oil/gas prone samples (resource areas). These were then distinguished from strata with very high organic matter samples as well as very high TOC to help identify for possible source rock characterizations within the lithology pertaining to the well in terms of potential source-reservoir-seals combinations. The Rock-Eval pyrolysis data were useful in assessing and evaluating the type of organic matter, thermal maturity, and the generation capability of source rocks for hydrocarbon exploration rationale. The analyses revealed that some strata, within the sampled well data, have high hydrocarbon generation potential with the existence of commercial hydrocarbon production

Time-Resolved Examination of Fungal Selenium Redox Transformations.

Selenium (Se) is both a micronutrient required for most life and an element of environmental concern due to its toxicity at high concentrations, and both bioavailability and toxicity are largely influenced by the Se oxidation state. Environmentally relevant fungi have been shown to aerobically reduce Se(IV) and Se(VI), the generally more toxic and bioavailable Se forms. The goal of this study was to shed light on fungal Se(IV) reduction pathways and biotransformation products over time and fungal growth stages. Two Ascomycete fungi were grown with moderate (0.1 mM) and high (0.5 mM) Se(IV) concentrations in batch culture over 1 month. Fungal growth was measured throughout the experiments, and aqueous and biomass-associated Se was quantified and speciated using analytical geochemistry, transmission electron microscopy (TEM), and synchrotron-based X-ray absorption spectroscopy (XAS) approaches. The results show that Se transformation products were largely Se(0) nanoparticles, with a smaller proportion of volatile, methylated Se compounds and Se-containing amino acids. Interestingly, the relative proportions of these products were consistent throughout all fungal growth stages, and the products appeared stable over time even as growth and Se(IV) concentration declined. This time-series experiment showing different biotransformation products throughout the different growth phases suggests that multiple mechanisms are responsible for Se detoxification, but some of these mechanisms might be independent of Se presence and serve other cellular functions. Knowing and predicting fungal Se transformation products has important implications for environmental and biological health as well as for biotechnology applications such as bioremediation, nanobiosensors, and chemotherapeutic agents.

Identification and Characteristics of Source Rocks in Lt-1 Well, Northern Kenya

This study on the hydrocarbon source rocks identification of LT-1 well in a Tertiary rift basin, northern Kenya, which had oil and gas shows was based on the organic matter quantity, quality, and the thermal maturation generation capability of the organic matter disseminated in the analysed rock samples. The organic matter contents were determined directly from laboratory analyses of the source rock samples with the help of seismic and gamma-ray profiles, total organic carbon (TOC wt%), maturity indices (HI and PI), temperature maximum (Tmax °C), porosities and other sedimentological parameters. This study involved a series of analytical geochemistry and petro-physical studies in ascertaining a number of effective source rock samples from the well cores which were then analysed in terms of TOC, PI, HI, S2, S1 and Tmax to determine oil/gas prone samples (resource areas) and distinguish them from strata with very high organic matter content. The samples with very high TOC were identified for possible source rock characterisations of the lithology pertaining to the well in terms of potential source-reservoir-seals associations. The Rock-Eval pyrolysis data were useful in assessing and evaluating the type of organic matter, thermal maturity, and the generation capability of source rocks for hydrocarbon exploration rationale. The analyses revealed that some strata within the sampled well data have high hydrocarbon generation potential with the existence of commercial hydrocarbon production. In conclusion, after an in-depth comparison and study of organic carbon content, hydrogen and production indices, type of organic matter content and maturity of organic matter, we confirmed that the studied resource areas are favourably considered for medium- to large-size hydrocarbon discoveries.

The Sedimentary Geochemistry and Paleoenvironments Project.

The Sedimentary Geochemistry and Paleoenvironments Project.

SOME PROTECTIONS ON THE ROLE OF GEOCHEMICAL PROPERTIES OF CHEMICAL ELEMENTS IN THE PROBLEMS OF ENVIRONMENTAL POLLUTION AND PROTECTION

The article discusses various limited considerations and assumptions on the positive or negative impact of geochemical features chemical elements found in rocks, ores, soil, plants, water and in the air of the territories of populated areas, factories, the mining and agro-industrial complexes to the environment and the role of analytical geochemistry in this process. According to the author, one of the main points on which the light should be shed is the role of finding elements (independent, combination or isomorphic mixture) rather than their existence in different amounts in the environment. Thus, the chemical elements can be more or less hazardous to environment regardless its amount, but the finding methods. Chemical and natural combinations can be either very hazardous or very useful to all living creatures depending on their characteristics, so it’s better to determine their environmental hazardousness via their impact to a particular human or animal organ which in turn facilitates the solution of the problem. Moreover, it should be noted that the most environmentally dangerous and active chemical elements are the ones with fluctuating valence. Some elements are not so hazardous when they are independent or in solid form since they change weakly. But they are very dangerous when they turn into liquid or gas forms and create mineral compounds with other elements such as halkofil group of elements which in turn can easily decompose and dissolve in water by causing dangers to all living creatures in the nature. Approximately any chemical element can either react negatively or in most cases stimulate the life functions of the organs of animals and plants depending on its finding forms. The study of geochemical parameters in different natural objects such as surface and subsoil water, air, rocks and ores can be very helpful in organizing the protection of environmetal and the solution of its problems. X-ray Spectral analysis is particularly highlighted in this article for identifying various chemical elements in geological and ecological objects. There are several advantages of X-ray Spectral analysis such as its productiveness and low cost, the expressiveness and simplicity of analysis operations, having slightly high sensitivity, universality, high range of elements identification features, etc. To conclude some authors claim that the following problems can be solved with the help of analytic geochemistry: Identifying the main source of pollution and the evaluation of its impact on the environment; Identification of quantitative and qualitative parameters of sources of natural, techno and agro genic pollution in the settlements, industrial objects and in the regions of developed mining complexes; Eco-geochemical and biochemical evaluation of the negative impact of water, weather and harmful geochemical anomalies on live organisms. We hope the elimination of this type of problems can pave the way to the ecologically clean environment. Keywords: ore, soil, plant, water, weather.

Generative potential, thermal maturity, and TOC modeling of petroleum systems in Southwestern Khuzestan Province, Zagros Basin, Iran

ABSTRACT In this study, a series of analytical geochemistry and petro-physical studies has been done to a number of effective source rock samples in the southwestern region of Khuzestan province and it illustrates that some strata’s in investigated wells have high hydrocarbon generation potential with the existence of commercial hydrocarbon production. There are some practical drawbacks to these analytical strategies, which can be solved through a combination of the results of different analyses, such as Thermal maturity, TOC, Rock Eval analysis that the main reason behind implementing different strategies in this paper. Twenty-five samples were analyzed in terms of TOC, PI, HI, OI, S3, S2, Tmax and we could determine oil/gas prone samples (resource areas) and distinguish them from strata’s with very low organic matter content Larter & Douglas, (1982). These predictions are quite crucial to E&P stage hydrocarbon exploitation as they will lead to solid predictions and they would avoid substantial expenses and eliminate uncertainties. In conclusion, after in depth comparison and study of organic carbon content, hydrogen and oxygen index, Type of organic matter content and Maturity of organic matter, we determined that studied resource areas are considered for medium to large size hydrocarbon discoveries and should be considered favorable.

Optimizing the organization of geochemistry research as a discipline in the National Natural Science Foundation of China

As a traditional discipline in the Department of Earth Sciences (DES) at the National Natural Science Foundation of China (NSFC), geochemistry is faced with new opportunities and challenges to serve the top-level strategy of the DES’s “Habitable Earth” program. The development of geochemistry as a discipline should be guided both by the forefront of scientific research and social demands and be driven by the innovation of analytical techniques. Optimizing application codes is of great importance to the organization of geochemistry research. Since the establishment of the NSFC, the application code system for geochemistry (D03) has included five stages, which undergoes a process of continuous improvement and development. Following reform guidance from the NSFC and DES, research to optimize the organization of geochemical disciplines was performed to identify defects of the existing code system and to propose new code scheme. This new scheme has a framework comprising three layers: Fundamental theories, analytical techniques, and applications. Research areas within fundamental theories include isotope geochemistry (D0301), elemental geochemistry (D0302), geochronology (D0303), and organic geochemistry (D0304). Analytical techniques comprise analytical geochemistry (D0305) and experimental and computational geochemistry (D0306). The applications are divided into basic (e.g., cosmochemistry (D0307) and petrogeochemistry (D0308)), resource and energy security (e.g., fossil fuel geochemistry (D0309) and ore deposits and exploration geochemistry (D0311)), and human activities and environments (e.g., surface geochemistry (D0310), biogeochemistry (D0312), atmospheric and marine geochemistry (D0313), and emerging and interdisciplinary geochemistry (D0314)). The objectives of optimizing the codes within the applications area are to develop a theoretical system, expand applications and enhance the use of geochemistry for national needs. Overall, technical methods, interdisciplinary aspects and applications, and emerging areas of research comprise the basic content. The new analytical geochemistry area aims to enhance research on analytical techniques, address problems, and provide critical support for geochemical development. Another new section, surface geochemistry, has a strong focus on geochemical composition, source, and spatiotemporal evolution of constituent units of the Earth surface system at present and throughout geological history. It aims to describe the circulation of materials and conversion of energy between these Earth systems as well as corresponding effects on ecology, resources, and the environment. Surface geochemistry research will investigate the evolution of Earth surface systems under the influence of human activities to provide evidence for future environmental change as well as aid the sustainable development of human society. Atmospheric and marine geochemistry research focuses on material resources and the composition and evolution of the atmosphere and oceans using element analyses, isotopes, and other geochemical methods. The aim is to reveal the processes and mechanisms for materials and energy within the atmosphere, ocean, and surface realms, along with their corresponding effects on climate, the environment, ecology, and resources. This will provide evidence for subsequent research within the programs “Habitable Earth” and “Earth System Science” and aid the sustainable development of human society. The new emerging and interdisciplinary geochemistry theme focuses on the integration of geochemistry with computing technology and biotechnology and will study scientific problems related to the development and needs of modern society. By outlining this overall new research scheme in DES, we hope to stimulate research interest in these areas at the NSFC and build strong geochemistry research teams, which will allow the NSFC to play a significant role in basic research in China.

Validation of sampling antarctic subglacial hypersaline waters with an electrothermal ice melting probe (IceMole) for environmental analytical geochemistry

ABSTRACT Geochemical characterisation of hypersaline waters is difficult as high concentrations of salts hinder the analysis of constituents at low concentrations, such as trace metals, and the collection of samples for trace metal analysis in natural waters can be easily contaminated. This is particularly the case if samples are collected by non-conventional techniques such as those required for aquatic subglacial environments. In this paper we present the first analysis of a subglacial brine from Taylor Valley, (~ 78°S), Antarctica for the trace metals: Ba, Co, Mo, Rb, Sr, V, and U. Samples were collected englacially using an electrothermal melting probe called the IceMole. This probe uses differential heating of a copper head as well as the probe’s sidewalls and an ice screw at the melting head to move through glacier ice. Detailed blanks, meltwater, and subglacial brine samples were collected to evaluate the impact of the IceMole and the borehole pump, the melting and collection process, filtration, and storage on the geochemistry of the samples collected by this device. Comparisons between melt water profiles through the glacier ice and blank analysis, with published studies on ice geochemistry, suggest the potential for minor contributions of some species Rb, As, Co, Mn, Ni, NH4 +, and NO2 −+NO3 − from the IceMole. The ability to conduct detailed chemical analyses of subglacial fluids collected with melting probes is critical for the future exploration of the hundreds of deep subglacial lakes in Antarctica.

Encyclopedia of Geochemistry

Acid Deposition. Acids and Bases. Actinium. Activation Energy, Activation Enthalpy, Activation Volume. Activity and Activity Coefficients. Aluminum. Americium. Analysis: field methods. Analytical Geochemistry. Analytical Techniques. Antimony: Element and Geochemistry. Aqueous Solutions. Argon. Argon-40 - Argon-39 Dating Method. Arsenic. Astatine. Atomic Absorption. Atomic Mass Unit, Avogadro constant and mole. Atomic Number. Authigenesis. Barium. Berkelium. Beryllium. Biogenic methane and gas hydrates. Biogeochemistry. Biomarker: aliphatic. Biomarker: aromatic. Biomarker: assessment of thermal maturity. Biomarker: coals. Biomarker: higher plant. Biopolymers and macromolecules. Bismuth: Element and Geochemistry. Black shales and sapropels. Boron. Bromine. Cadmium. Calcium. Calcium Carbonate and the Carbonic Acid Systems. Californium. Calorimetry. Carbon. Carbon-14 Dating and other applications. Carbon Cycle. Carbon Isotopes. Carbonate Compensation Depth. Carbonate Sediments. Cerium. Cesium. Chelation. Chemical Kinetics. Chlorine. Chromium. Clapeyron's Equation. Clay Membranes. Clay Minerals - Ion Exchange. Coal: Organic petrography. Coal: origin and diagenesis. Coal: Types and characteristics. Coal: Vitrinite reflectance and maturity assessment. Cobalt. Colloids. Complexes. Compound-specific isotope GC-MS. Copper. Cosmic Elemental Abundances. Cosmogenic Nuclides. Counters. Critical Points. Crystal Chemistry. Crystal Field Theory. Crystal Growth. Curium. Dating Methods. Debye-Huckel Equation. Diagenesis. Differential Thermal Analysis and Scanning Calorimetry. Diffusion. Dolomite and Dolomitization. Dysprosium. Earth's Atmosphere. Earth's Continental Crust. Earth's Core Geochemistry. Earth's Formation and Geochemical Evolution. Earth's Mantle Geochemistry. Earth's Ocean Geochemistry. Earth's Oceanic Crust. Eh-pH Relations. Einsteinium. Electrolyte Theory. Electron Capture. Electron Microprobe. Electronegativity. Elementary Particles. Elements: Actinide Series. Elements: Alkali and Alkaline Earth. Elements: Chalcophile. Elements: Distribution. Elements: Halogens. Elements: Heat Producing. Elements: High Field Strength. Elements: Incompatible. Elements: Lanthanide Series, Rare Earths. Elements: Large Ion Lithophile. Elements: Lithophile. Elements: Metalloids. Elements: Noble Gases. Elements: Platinum Group. Elements: Radioactive. Elements: Siderophile. Elements: Trace. Elements: Transitional. Enthalpy. Entropy. Epigenesis. Equilibrium. Equilibrium Constant. Erbium. Europium. Experimental Mineralogy and Petrology. Exsolution. Fermium. Fick's Laws. Fission Track Analysis. Fluid rock interactions. Fluids in Volcanic and Plutonic Environments: Evidence from Fluid Inclusions. Fluorine. Francium. Free energy. Fugacity. Gadolinium. Gallium: Element and Geochemistry. Gas chromatography Mass Spectrometry (GC-MS). Gas source mass spectrometry. Geoavailability. Geochemical Classification of the Elements. Geochemical Exploration. Geochemical reference materials. Geochemical Tectonics. Geochemical Thermodynamics. Geochemistry. Geochemistry: Low Temperature. Geochemistry of Sediments. Geochronology and Radio Isotopes. Geologic Time Scale. Geothermal Systems. Geothermometers. Geothermometry and Geobarometry. Germanium: Element and Geochemistry. Gibbs-Duhem Equation. Gold. Hafnium. Helium. Helium isotopes. Henry's Law. History of Geochemistry. Holmium. Hydrocarbons. Hydrogen. Hydrogen Isotopes. Hydrologic Cycle. Hydrothermal Alteration. Hydrothermal Solutions. Hypogene. Indium: Element and Geochemistry. Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Iodine. Ion Exchange Chromatography. Ion Microprobe. Ionic Radii. Iridium. Iron. Isotope Dilution. Isotope Fractionation. Krypton. Laboratory Simulations of Oil and Natural Gas Formation. Lanthanum. Laser ablation inductively coupled mass spectrometry ICPMS. Lawrencium. Lead. Lead: Stable isotopes. Lipid biomarker. Lipids (Eubacteria and Archaebacteria). Lithium: Element and Geochemistry. Luminescence. Lutetium. Lutetium-Hafnium Decay System. Magmatic Processes. Magnesium. Magnetism. Manganese. Mass Transfer. Mendelevium. Mercury. Metamorphic Environments: chemical mobility. Meteorites. Micro-Raman spectrometry. Mid Ocean Ridge Basalts (MORB). Mineral Defects. Mineral Genesis. Mineralogy. Molybdenum. Mossbauer Spectroscopy. Natural gas. Natural Resources. Neodymium. Neodymium in Igneous Rocks. Neodymium in Sedimentary Rocks. Neon. Neptunium. Neutron Activation Analysis. Nickel. Niobium. Nitrogen. Nitrogen Cycle. Nitrogen Isotopes. Nobelium. Nucleosynethesis. Nutrients. Occurrence of Organic Facies. Oil seeps and Coastal Bitumens. Oil shales. Oil-oil and oil-source rock correlation. Oklo Natural Nuclear Reactor. Onuma Diagrams. Ore Deposits. Organic Geochemistry. Organic Matter in Fossils. Organic matter in meteorites. Organics: Contemporary degradation and preservation. Organics: Sources and depositional environments. Osmium. Oxidation-Reduction. Oxygen. Oxygen Isotopes. Paleo-sea surface temperature estimation. Paleoenvironments. Paleoproductivity. Paleotemperatures. Palladium. Paragenesis. Particle-Induced X-ray Emission (PIXE). Partition Coefficients. Peat. Periodic Table. Petroleum. Petroleum: hydrothermal. Petroleum: in-reservoir biodegradation. Petroleum: kinetic modeling. Petroleum: primary migration. Petroleum: surface geochemistry. Petroleum: types, occurence and reserves. Phase Equilibria. Phosphorus. Platinum. Plutonium. Polonium. Porphyrins. Potassium. Potassium-Argon Dating Method. Potassium-Calcium Decay System. Praseodymium. Precambrian Atmosphere. Precambrian Geochemistry. Precambrian organic matter. Promethium. Protactinium. Quantum Numbers. Radioactivity. Radium. Radon. Rare Earth Element Tetrad Effect. Remote Sensing. Rhenium. Rhenium - Osmium Dating Method. Rhodium. Rock-eval pyrolysis. Rocks. Rubidium: Element and Geochemistry. Rubidium Strontium Method. Ruthenium. Samarium. Samarium - Neodymium. Sampling. Scandium. Scanning Electron Microscope (SEM). Sedimentary Fluids. Selenium. Silicon, Silica. Silver: Element and geochemistry. Sodium. Soil. Solid Solution. Solubility. Spectrophotometry. Stable Isotopes. Standard States. Steroidal compounds. Stoichiometry. Strontium: Element and Geochemistry. Strontium in Igneous Rocks. Strontium in Sedimentary Rocks. Sulfate Minerals. Sulfate Reduction. Sulfide Minerals. Sulfides in mafic and ultramafic rocks. Sulfosalt Minerals. Sulfur. Sulfur Cycle. Sulfur Isotopes in Geochemistry. Supergene. Surface Geochemistry. Synchrotron X-ray analysis. Syngenesis. Tantalum. Technetium. Tellurium. Terbium. Thallium. Thermal ionisation mass spectrometry. Thermochemistry. Thermogravimetry. Thermoluminescence. Thixotropy. Thorium. Thulium. Tin. Titanium: Element and Geochemistry. Trace Element Partitioning Models. Tritium. Tungsten. Uranium. Uranium-Lead Thorium-Lead Decay System. Uranium Series Disequilibria. Van der Waals Force. Vanadium. Volcanic Gases. Volcanism. Water. Water: Fresh. Weathering: Chemical. X-ray Diffraction (XRD). X-Ray Fluorescence. Xenon. Ytterbium. Yttrium. Zinc. Zirconium: Element and Geochemistry.

Proper Terminology in Analytical Geochemistry

Proper Terminology in Analytical Geochemistry

Comments: Shale Sustainability

Editor's column Public and government concern over unconventional oil and gas production continues. Hardly a month goes by before another study into the potential health effects of shale production is launched or a public hearing is conducted regarding the impact of a project on the local landscape. For example, last month the Southwest Pennsylvania Environmental Health Project opened a public health registry to track and analyze the impact of shale gas development on people living near wells, pipelines, and other infrastructure. That followed the release of a Duke University study that concluded that hydraulic fracturing in the Marcellus Shale did not pollute groundwater in West Virginia but that wastewater spillage contaminated some surface water. Many of the reports and studies are drawing similar conclusions—that hydraulic fracturing poses little or no risk but that contamination can occur during the transportation or treatment process. Shale oil and gas development has certainly changed the world order in these commodities, from OPEC strategy and commodity prices to global import/export patterns. The US, with abundant gas still depressing prices, is becoming an exporter of liquefied natural gas rather than an importer. Shale oil is largely responsible for the low oil prices of the past 2 years, turning the US into the world’s “swing” producer, a position Saudi Arabia once held. Industry resiliency amid low oil prices led to slashing of service company costs, operational efficiencies, and high-grading of properties. As service costs now begin to rise, profitable production in a world of USD 40–60/bbl oil will require further innovation. But the industry also continues to face regulatory challenges based on environmental concerns. Maryland has recently followed New York in legislating against hydraulic fracturing. A new book, Sustainable Shale Oil and Gas: Analytical Chemistry, Geochemistry, and Biochemistry Methods by Vikram Rao and Rob Knight argues that this type of policymaking is hampered by inadequate data, which in turn is caused by shortcomings in analytical techniques. The authors describe new cost-effective analytical methods for detecting fugitive methane as well as particulate matter and volatile organic chemicals, including a portable shoe-box-sized mass spectrometer with performance approaching that of a laboratory machine. The last line of the book states, “That which cannot be measured, cannot be regulated or otherwise controlled or exploited.” They apply this reasoning to improving the economics of recovery as well. The book discusses analytical methods to illuminate the unconventional reservoir, including a fascinating method using DNA sequencing to characterize reservoir rock through examination of microbial populations. The book lays out how analytical chemistry, geochemistry, and biochemistry play prominent roles in hydraulic fracturing and that they are central to the three tenets of sustainable production: protecting the environment, protecting the well-being of local communities, and profitability. Innovation has been a necessity for survival in the low oil and gas price market, and continued innovation will result in an industry resilient to future unexpected challenges. And the authors contend that that innovation and production is achievable in environmentally responsible fashion.

Introduction to IAGS Tuscon 2015 volume

This issue of GEEA presents a small selection of papers read at the 24th International Applied Geochemistry Symposium (IAGS), 20–24 April 2015 at the Hilton El Conquistador Golf & Resort, Tucson, Arizona, USA. The meeting was convened by Eric Weiland, Sarah Lincoln and myself, and attracted 240 participants from 24 countries who presented 90 oral and 60 poster presentations. The conference covered themes in exploration geochemistry; lithogeochemistry; geochemistry in government surveys; mine waste and environmental geochemistry; geochemistry and health; biogeochemistry; hydrogeochemistry; isotope and analytical geochemistry; and a special session on geochemistry in the Desert South West.

Analytical geochemistry in the service of medicine: An experimental study of urinary stones from Northern Greece

Knowledge of the precise human biomineral composition may allow physicians to recommend an appropriate prophylactic therapy for the patient and thus prevent or delay the stone recurrence. The present study focuses on the application of complementary analytical techniques to the characterization of human urinary stones. Several gallbladder and renal stone samples were obtained from patients dwelling in areas of northern Greece. A comprehensive analytical study took place, employing the following, common in analytical geochemistry, techniques: Environmental Scanning Electron Microscopy (ESEM) coupled to Energy Dispersive System (EDS), X-Ray Diffraction (XRD), thermogravimetry (TG), μRaman spectroscopy and Cathodoluminescence (CL). A detailed determination of morphological, micro-structural, molecular, chemical and mineralogical characteristics of the urinary stone samples was achieved. It was evident by our study the application of powerful analytical techniques could substantially help the medical advisors to ascribe a medical treatment of diseases related to stone formation.

Evaluation of Major to Ultra Trace Element Bulk Rock Chemical Analysis of Nanoparticulate Pressed Powder Pellets by LA‐ICP‐MS

An efficient, clean procedure for the measurement of element mass fractions in bulk rock nanoparticulate pressed powder pellets (PPPs) by 193 nm laser ablation ICP‐MS is presented. Samples were pulverised by wet milling and pelletised with microcrystalline cellulose as a binder, allowing non‐cohesive materials such as quartz or ceramics to be processed. The LA‐ICP‐MS PPP analytical procedure was optimised and evaluated using six different geological reference materials (JP‐1, UB‐N, BCR‐2, GSP‐2, OKUM and MUH‐1), with rigorous procedural blank quantification employing synthetic quartz. Measurement trueness of the procedure was equivalent to that achieved by solution ICP‐MS and LA‐ICP‐MS analysis of glass. The measurement repeatability was as low as 0.5–2% (1s, n = 6) and, accordingly, PPP homogeneity could be demonstrated. Calibration based on the reference glasses NIST SRM 610, NIST SRM 612, BCR‐2G and GSD‐1G revealed matrix effects for glass and PPP measurement with NIST SRM 61×; using basalt glasses eliminated this problem. Most significantly, trace elements not commonly measured (flux elements Li, B; chalcophile elements As, Sb, Tl, In, Bi) could be quantified. The PPP‐LA‐ICP‐MS method overcomes common problems and limitations in analytical geochemistry and thus represents an efficient and accurate alternative for bulk rock analysis.

Recent Contributions in the Field of Sediment Geochemistry

Sediment geochemistry is a powerful tool to investigate earth surface processes because sediments record geochemical signatures of their provenance, generation, transport, deposition, and environmental conditions. A significant advancement in the technology of analytical geochemistry has made geochemical analyses of sediments more rapid and precise, which together provided an impetus to the study of sediment system. As a result, high-quality research papers on sediment geochemistry have been published during the last five years from India. A foreseeable growth of research and an increase in the publication are likely in the future because of the new set-ups of state- of the- art analytical instruments for geochemical research at various research and academic institutions in India. Here we are presenting the published important work on sediment geochemistry under three categories, i.e., weathering, erosion, deposition and provenance determination; sediment geochemistry as palaeoclimate proxy; and environmental geochemistry.

GGR Biennial Critical Review: Analytical Developments Since 2012

Advances in the chemical, crystallographic and isotopic characterisation of geological and environmental materials can often be ascribed to technological improvements in analytical hardware or to innovative approaches to data acquisition and/or its interpretation. This biennial review addresses key laboratory methods that form much of the foundation for analytical geochemistry; again, this contribution is presented as a compendium of laboratory techniques. We highlight advances that have appeared since January 2012 and that are of particular significance for the chemical and isotopic characterisation of geomaterials. Prominent scientists from the selected analytical fields present publications they judge to be particular noteworthy, providing background information about the method and assessing where further opportunities might be anticipated. In addition to the well‐established technologies such as thermal ionisation mass spectrometry and plasma emission spectroscopy, this publication also presents new or rapidly growing methods such as electron backscattered diffraction analysis and atom probe tomography – a very sensitive method providing atomic scale information.

Abiogenic synthesis of oligopeptides in the open space

Exobiology is a relatively new field of sciences, which was established in connection with the development of the space technology, expanding the range of biological studies beyond the Earth. The major task of exobiology is the study of processes that give rise to the life, biological evolution, and distribution of living creatures in the universe. The term exobiology was introduced by the Dutch researcher Lederberg (1960). During fifty years of progressive development, it turned into a wide interdisciplinary field of sciences, including a number of disciplines, such as astrophysics, organic and analytical chemistry, geology, geochemistry, and other planet sciences not to mention various biological disciplines. Exobiology has become an inherent part of national and international space programs (Carle et al., 1992; Morrison, 2001).

CO2–H2O–coal interaction of CO2 storage in coal beds

In order to study the physical and chemical reaction after CO2 injected into coal beds at different condition. The physical and chemistry reaction among CO2, H2O and coal was studied, and the influence on permeability and porosity of coal beds was carried out. The experimental method was used, so did the basic theory of mineralogy, coal petrology, geochemistry, analytical geochemistry and physical chemistry. In this experiment, the changes of mineral and permeability of coal and water quality were observed through CO2 solution reacting with different coal samples. The differences could be found out by comparing the properties and microcrystalline structure before and after the reaction. There are three results were carried out: First, the content of carbonate in coal beds decreases because of the dissolution reaction between carbonate minerals and CO2 solution, and precipitation is formed by reaction of chlorite and orthoclase. Second, the result that permeability and porosity of coal beds are improved after the reaction is proposed. Third, the initial permeability of different coal samples plays a great role on the reaction, and the improvement of permeability is not obvious in the samples which have too low or too high permeability, and the improvement is good in medium permeability (0.2–3mD).

Straightforward synthesis of 2,2,4,4,5,7,7-d7-cholestane: a new deuterated standard in petroleum analysis

A short and efficient synthesis of heptadeuterated 2,2,4,4,5,7,7-d7-cholestane (1) from cholesterol (3) is described. The deuterated material will be useful for the analysis of different sources of petroleum in analytical geochemistry laboratories as internal standard for quantification of steranes via gas chromatography-mass spectrometry (GC-MS).

Foreword to the special issue on I Reunión Argentina de Geoquímica de la Superficie (I RAGSU) (First Argentine meeting on geochemistry of the earth’s surface)

Geochemical understanding can be traced as far back as prehistory with the development of bronze and iron tools. This initiated a path that eventually led to the current knowledge on metal identification and processing. The geochemical discipline, however, has its origin hand-in-hand with geological science; first, during the 19th century when analytical chemistry and later physical chemistry promoted the superlative geochemical knowledge growth seen today. As is generally known, there are a number of diverse specialties within the wide field encompassed by geochemistry. One of them is the geochemistry of earth’s surface processes, which is mainly oriented to understand the chemical mechanisms that take place in the ‘‘critical zone’’, the relatively thin layer where the interaction of the atmosphere, biosphere, hydrosphere, and lithosphere, takes place. On the other hand, the current environmental crisis has triggered a large number of scientific studies worldwide, which mainly seek to unveil anthropogenic environmental problems and find corrective measures to minimize undesirable impacts. The first meeting, I RAGSU, was envisioned to probe into the geochemical nature of the processes occurring on the surface of the earth and took place at the city of Cordoba (Argentina), between the 27th and the 30th of September, 2009. The meeting was hosted by Argentina’s Academia Nacional de Ciencias (http://www.acad.uncor. edu/) and was jointly organized by the Academy and the Centro de Investigaciones en Ciencias de la Tierra (CICTERRA, http://www.cicterra-conicet.gov.ar/) and the Centro de Investigaciones Geoquimicas y de Procesos de la Superfice (CIGeS, http://www.efn.unc.edu.ar/investigacion/ ciges/). Although organized by earth scientists, the goal was to assemble as many environmental scientists as possible (e.g., biologists, agronomists, chemists, geologists). Almost 90 scientists and advanced students attended the meeting at Argentina’s Academia Nacional de Ciencias. Sixty-two research papers were presented, either as oral presentations (27) or as posters (35). Initially conceived as a national get-together of Argentine surface geochemists, it was expanded to include attendees from neighboring nations (e.g., Brazil, Chile), Europe (France, Switzerland), and the Americas (e.g., USA, Venezuela). Daniel Ariztegui (University of Geneva, Switzerland); Jay A. Brandes and Herbert L. Windom (Skidaway Institute of Oceanography, Savannah, Georgia, USA); Luis Felipe Niencheski (FURG, Rio Grande, Brazil); Sandor Muslow (Universidad Austral de Chile, Concepcion, Chile); and Christine Vallet-Coulomb (Aix-Marseille Universite, Aix en Provence, France) were in charge of six key presentations. Seven oral and poster presentations covered the following topics: (1) environmental geochemistry, (2) hydrogeochemistry, (3) biogeochemistry, (4) marine geochemistry, (5) isotopic geochemistry, (6) sedimentary and soil geochemistry, (7) analytical geochemistry. Within the framework of the meeting, three short actualization courses were given: ‘‘Introduction to weathering processes’’, ‘‘Geochemistry of the solid–liquid interface’’, and ‘‘Biogeochemistry: origins and global cycles’’. Discussions were interesting and lively, and the initial icebreaker as well as the final dinner gave the opportunity to exchange views, socialize, and program future jointventures. I RAGSU was the initial step in what is visualized as the beginning of a long sequence of regional P. J. Depetris A. I. Pasquini (&) Centro de Investigaciones en Ciencias de la Tierra (CICTERRA-CIGeS, CONICET-UNC), Av. Velez Sarsfield 1611, X5016GCA Cordoba, Argentina e-mail: apasquini@com.uncor.edu