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Molecular processes in nature affect human health, the availability of resources and the Earth's climate.Molecular modelling is a powerful and versatile toolbox that complements experimental data and provides insights where direct observation is not currently possible.

This first book to discuss both separation chemistry and mass spectrometry for mineral and rock analysis compares the two frequently used techniques, analyzing both their scope and limitations by way of numerous practical examples. The excellent and highly experienced author adopts a comprehensive and systematic approach, reviewing all the steps involved in an analytical workflow. In addition to thermal ionization mass spectrometry (TIMS), he also discusses applications of ICP-MS. Furthermore, alongside detailed protocols on sample preparation and mass spectrometric measurements, numerous practical hints are given. A must-have handy guide for all isotope geochemists and anyone involved in isotope analysis.

Hydrogeochemical and stable isotope analyses and geochemical modeling were carried out to identify the major geochemical processes controlling the groundwater chemistry and fluoride contamination in the aquifers of the Yuncheng Basin, China, an area with complex hydrogeochemical conditions and severe fluoride contamination of the groundwater. The major findings of this case study include the following: 1) Cation exchange and salt effects are vital controls on the enrichment of fluoride in groundwater in the area by reducing the activity of Ca2+/F- in groundwater via ion complexation. Cation exchange increased the fluoride concentration by 2.7 mg/L when the Na/Ca molar ratio increased from 0.24 to 9.0, while the salt effect led to a ca. 5-10% increase in complex F- in groundwater due to the further dissolution of fluoride-bearing minerals in the aquifers, as suggested by a model calculation. 2) Anthropogenic contamination from pesticide and fertilizer use and industrial waste discharge is also a main source of fluoride in the groundwater. 3) Evaporation and ion effects favor the enrichment of fluoride in groundwater by encouraging the removal of Ca via precipitation. 4) The desorption of fluoride from mineral/organic matter surfaces is enhanced under alkaline conditions and a high HCO3 content in groundwater.

We propose a new reaction device for the microdiffusion analysis of CO.sub.2 in fluid samples from volcanic areas to improve the conventional analysis procedure, which requires a fixative and good handling skills. To accomplish this, a small resin reaction cell for the sample solution and acid (initiator for CO.sub.2 liberation) was devised and placed in a commercially available air-tight glass container with a Petri dish to form a microdiffusion analysis unit. The analysis was based on the principles of the conventional manual titration method that uses Ba(OH).sub.2 as the CO.sub.2 absorbent. Using the new device, 99.5% recovery, with a relative standard deviation of 4.5% (n = 8), was achieved in a test analysis for 0.03 mmol of CO.sub.2 liberated from a Na.sub.2CO.sub.3 solution as a simulated sample. The analytical performance of the new device was almost comparable to that of conventional units under the experimental conditions of this study. Applying this new device for analyzing fluid samples from volcanic areas will contribute to enhancing the performance by reducing the possibility of CO.sub.2 contamination and by simplifying the process by eliminating the need for preparatory cleaning for fixative application.

Utilizing geochemical analysis, this study identifies the sources of European brass used in the casting of the renowned Benin Bronzes, produced by the Edo people of Nigeria. It is commonly believed that distinctive brass rings known as “manillas”, used as currency in the European trade in West Africa, also served as a metal source for the making of the Bronzes. However, prior to the current study, no research had conclusively connected the Benin artworks and the European manillas. For this research, manillas from shipwrecks in African, American and European waters dating between the 16th and 19th Century were analysed using ICP-MS analysis. Comparing trace elements and lead isotope ratios of manillas and Benin Bronzes identifies Germany as the principal source of the manillas used in the West African trade between the 15 th and 18 th centuries before British industries took over the brass trade in the late 18 th century.

The Middle Woodland period witnessed elaborate social and economic networks involving several different sites. While the Hopewell Interaction Sphere (HIS) typifies the level of trade and exchange among large sites like Leake located in north Georgia, smaller sites were engaged in resource extraction activities. One of the critical components of these economic networks was the extraction of stone resources to create lithic tools. Investigations at the George Smith Site, located in Bartow County, Georgia, have revealed significant quantities of lithic material. This paper seeks to determine the source of the stone used to create the lithic material found at the George Smith Site by examining their geochemical makeup.

The definition of the chemical and isotopic composition of the groundwater present in argillaceous formations, which are considered as potential host rocks for radioactive waste disposal, is crucial for establishing their barrier properties. Therefore, a critical review of the relevant literature on the current methods applied to extract water and solutes and on the various approaches to the interpretation of their results was commissioned to the Laboratoire d’hydrologie et de géochimie isotopique (Université de Paris-Sud, France). The present document provides a synthesis of available extraction methods, assesses their respective advantages and limitations, identifies key processes that may influence the composition of the extracted water, describes modelling approaches that are used to determine in situ porewater composition, and highlights, wherever possible, some of the unresolved issues and recommendations on ways to address them.

The four-step Tessier sequential extraction procedure is a well-known approach used for environmental and geochemical studies in soil and sediments. However, a lack of reference materials limits its use making implementation and quality control cumbersome. This study applied Tessier sequential extraction to three globally used marine sediment certified reference materials (CRMs) including HISS-1, MESS-4, and PACS-3 with varying levels of contamination. The study analyzed the distribution of 17 elements throughout the extraction phases. Overall, the percent recovery (sum of steps vs total metal concentration) of all analyzed elements in Tessier extraction was 92% + 40% in HISS-1, 101% + 12% in MESS-4, and 102% + 10% in PACS-3. The observed uncertainty of the individual elemental concentrations averaged at 13%, which compares favorably with the 16% target uncertainty derived from the Horwitz equation. The reference data set produced here using the Tessier sequential extraction procedure will serve as a quality control and method development tool for laboratories.

Terra rossa is a reddish clay soil which is often present on the surface of limestone in regions with a Mediterranean-type climate. Its genesis is a controversial subject in terms of the origin of the parent material, from the residuum of underlying (carbonate/dolomite) bedrock in the absence/presence of an external silicate contribution (e.g., aeolian dust). Within this context the main goal of the present work was the understanding of the geochemical processes leading to the formation of the terra rossa starting from the carbonate bedrock. We report the results of a multi-method analysis on a terra rossa deposit occupying the bottom of a Quaternary karst depression on Mesozoic limestones exposed in the Murge area (Apulia Foreland, southern Italy). Geological, petrographic, textural, and chemical data were collected on karst products (reddish calcite incrustations and nodules, and fine-grained portion of terra rossa) by a detailed field mapping, optical microscopy, XRF and fusion ICP/MS analyses and by scanning electron microscope. New collected data show that the mineralogical composition of reddish incrustations and nodules is comparable, consisting of fibrous and impure calcite, detrital fragments of quartz, K-feldspar, zircon and authigenic minerals as (Mn, Ba, Ca) phases, (Al, Si, Mn, Fe, Mg, Ba, Ca) minerals, Fe-kaolinite and anatase. The prevailing minerals, instead, in the fine-grained portion of terra rossa are hematite, kaolinite, and goethite. Based on the chemical composition, and especially on REE patterns, a progressive interaction of silicate aqueous solutions (with Al, Si, Fe), containing pelite material, with the calcareous bedrock, as a source of carbonic acid, was the process driving the formation of terra rossa. Obtained results add new elements to the definition of the long-lasting question about the genetic processes responsible for the formation of terra rossa, corroborating their polygenetic origin, as result of limestone alteration in conjunction with the chemical interaction with allochthonous siliciclastic material.

(Parent with price) Volume I contains subjective reviews, specialized and novel technique descriptions by guest authors. Part 1 includes contributions on purely analytical techniques and Part 2 includes matters such as development of mass spectrometers, stability of ion sources, standards and calibration, correction procedures and experimental methods to obtain isotopic fractionation factors.Volume II will be available in 2005.