This paper reports the extended study from a previously-described study on As and F contaminated groundwater from a small village, Kalalanwala, in east Punjab, Pakistan (Farooqi et al., 2007). Of the 147 groundwater samples investigated, 91% exceeded the WHO standard (10 μg/L) for As and 75% exceeded the WHO standard (1.5 mg/L) for F^-. The highly contaminated As (max. 2400 μg/L) and F^- (max. 22.8 mg/L) groundwaters were found from shallow depths down to 30 m from the surface. The contaminated groundwaters are characterized by high pH (max. 8.8), alkalinity (HCO₃^- up to 1281 mg/L), SO₄^2- (max. 960 mg/L), Na⁺ (max. 1058 mg/L) and maximum electric conductivity >4.6 mS/cm. Fluoride concentrations showed positive correlations with those of Na⁺ and HCO₃^- and negative ones with Ca²⁺ and Mg²⁺. The alkaline waters were saturated with calcite in spite of the low Ca²⁺ concentrations. Fluoride concentration is governed by fluorite solubility. Speciation analysis showed As is mostly in the form of As^V. There was a positive correlation between As and pH, while there is no relationship between As vs. Fe and F^-. Thus, the fluoride and As contamination occurred in the oxidizing and alkaline conditions of the groundwater. However, F^- and As are derived from two or more sources. Suspected contaminant sources in the study area contained considerable amounts of F^- and As; fertilizers (DAP, n = 5) contained leachable F^- ranging from 53-255 mg/kg, and As 5-10 mg/kg, and coals (n = 8) contained F^- ranging from 5-20 mg/kg. Sulfur isotopic ratios indicated that the high SO₄^2- in groundwater (3.2-7.0‰, CDT) is mainly derived from coal combusted atmospheric pollutants, fertilizers and household wastes. Nitrogen isotope data (8-30‰, Air) showed that NO₃^--N is attributed to animal waste distributed in the study area. The major chemical characteristics of the groundwaters are related with anthropogenic activities on the ground surface. The resultant major chemistry, especially highly alkaline and low Ca²⁺ and Mg²⁺ concentrations, must promote the high concentrations of F^- and As in the studied groundwaters.

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The study of heavy metal speciation is of interest for the evaluation of their ecotoxicological risk. Free heavy metal ion concentrations of Cu²⁺, Zn²⁺, Ni²⁺ and Cd²⁺ were studied at different soil to soil solution ratio (SSR) to discuss metal bioavailability and toxicity in circumstance. The samples were collected from two farmed soils, impacted by a cadmium rich zinc deposit, Guizhou, China. One is near a bridge (QBT for short), which is 15 km away from smelter and is regarded as polluted by fly ash from smelter, the other is located 300 m away from a smelting factory (BXT for short), and it is polluted badly by waste water from smelter. To determine the free heavy metal ion concentration, Donnan Membrane Technique (DMT) and ECOSAT program were used. The concentrations of free copper and zinc ions in QBT and all studied metal ions in BXT were nearly in direct ratio with the soil to soil solution ratio, and they increased with the increasing of SSR. The variational trends of the concentrations of free nickel and cadmium ions in QBT were contrary to those of copper and zinc ions. The measured and predicted results were compared and they agreed with each other. Individual sorbents contribution to metal binding was also predicted. The results suggest soil organic matter is the most important sorbents in the two soils, and hydrous ferric oxide takes the second place.

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Whole rock and mineral chemistry of amphibolites are presented for the lower (Gumusler Formation) and higher parts (Kaleboynu Formation) of the Nigde Massif with the aim to constrain protolith genesis and metamorphic P-T-conditions. The amphibolites, associated with a series of supracrustal metasediments, as thin layers and discontinuous pod/small lenses, are of igneous origin with composition of subalkaline and tholeiitic basalts. Based on immobile elements content and ratios, amphibolites from both formations are thought to have formed mostly by fractional crystallisation of pyroxene ± spinel, amphibole, plagioclase as well as apatite and titanite; coupled with minor crustal contamination. Contamination is particularly clear for the Gumusler Formation formed in a back-arc basin (Paleothetys) during magmatic ascent through the thickened Central Anatolian crust. The basic rocks could have been metamorphosed later at 7.5-3 ± 0.6 kb and 850-420°C, with the temperature gradient ranging from 35 to 122°C/km at different depths in the Neo-Tethyan subduction zone, and exhumed from depths of approximately 20 km via regional extension.

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Several cores from Krishna-Godavari (Western Bay of Bengal) and Goa (Eastern Arabian Sea) basins have been studied for pore water sulfate concentrations in order to understand and contrast the diagenetic processes. K-G sediments differ markedly from Goa sediments in pore water sulfate gradients and depth-integrated sulfate reduction rates. Significantly higher sulfate reduction rates in K-G sediments (3.6 to 15.8 nmol cm^-2day^-1), compared to that in Goa sediments (0.011 to 0.94 nmol cm^-2day^-1), can be attributed to higher sedimentation rates. Lower exposure time to oxygen for the organic matter in K-G sediments has preserved reactive organic compounds required for sulfate reducers and possibly methanogens. Authigenic carbonates with depleted carbon isotopic composition (δ¹³C = -48 to -50‰) at the base of the sulfate reduction zone in a core from K-G suggests anaerobic methane oxidation (AMO) process. The possibility, that the underlying methane gas hydrate zone is acting as a methane source for sulfate reduction can not be negated specially in light of the existing geophysical studies. Both methane and the fermentation products of organic matter degradation served as a substrate for sulfate reduction. However, a clear understanding of there relative importance needs further investigation.

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A detailed geochemical study of oil samples from an onshore field in the Niger Delta was carried out for their characterization and correlation. The samples were analyzed using Gas Chromatographic (GC), Gas Chromatographic-Mass Spectrometric (GC-MS) and Inductively Coupled Plasma-Mass Spectrometric (ICP-MS) analytical techniques. The results showed that CPI, Pr/Ph, Pr/nC₁₇, Ph/nC₁₈ and odd/even ratios ranged from 0.91 to 1.17, 3.07 to 6.04, 0.39 to 0.80, 0.14 to 3.30 and 1.33 to 1.39 respectively. The concentration levels of Co, Cr, Cu, Fe, Ni and V ranged from 0.9 to 32, 6.2 to 24, 3.31 to 19.4, 11.4 to 1241, 26.3 to 144 and 11.0 to 29.7 pbb respectively. The Pr/nC₁₇ vs. Ph/nC₁₈ plot revealed two oil types; non-degraded and minor degraded oils, which were derived from organic matter deposited in transitional environments. This suggests that both oil types have identical source rocks. Also, CPI values of 0.91 to 1.17 indicated that the oils are thermally mature. Biomarker data also discriminated the oils into two groups on the basis of biodegradation and revealed that the oils are mature and generated at almost the same thermal maturity level. The results of Ni vs. V, Co/Ni vs. V/Ni cross plots and cluster analysis similarly revealed identical two oil types. The similarity in the results of both organic and inorganic geochemistry of these oils shows that an integrated organic and inorganic geochemical data provide a reliable tool for the evaluation, characterization and correlation of crude oils.

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The stability and transformation of aqueous amino acid at high pressures and temperatures are very important in terms of the formation of interstellar organic matter, delivery of organic compounds of meteorolites, and prebiotic organic synthesis. We studied aqueous alanine saturated solid solution at pressures of several gigapascals and temperatures up to 500°C using an external heating hydrothermal diamond anvil cell (HDAC) through in situ observation and Raman spectroscopy. Five samples of initial pressures of 1.23, 1.98, 2.69, 2.78, and 3.67 GPa, which cause transformation from liquid solution to solid phase, are studied. The transformations of aqueous alanine solution are highly reliant on pressure, and with higher initial pressures, the transitions are retarded to higher temperatures. The melted solid alanine solution of the lowest initial pressure separates out a non-eutectic phase which takes on the characteristic of macro-organic matter, which indicates that amino acids can oligomerize or even polymerize at high pressures and temperatures. As for the highest initial pressure, the solid alanine solution remains almost intact up to the highest temperature of 500°C. The results show that pressure should be required to understand many occurrences of amino acids in space and meteorites.

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The mode of coordination about Cu(II) adsorbed on a strongly basic anion exchange resin equilibrated in HCl aqueous solutions was determined using extended X-ray absorption fine structure (EXAFS) and Raman spectroscopies. EXAFS spectra of the adsorbed Cu chloro-complexes were constant over a wide range of HCl concentrations in contrast to stepwise Cu-Cl complexation in the solutions. The adsorbed anion species was estimated to be [CuCl₄]^2-. Its Raman spectra suggested the most plausible coordination structure of [CuCl₄]^2- was 4 Cl coordination without H₂O ligands. The change from sixfold coordination [Cu(H₂O)₆]²⁺ to fourfold coordination [CuCl₄]^2- in stepwise chloro-complexation in the aqueous phase and preferential adsorption of [CuCl₄]^2- to the resin through ion-exchange reactions in elevated HCl concentrations will result in larger mass fractionation of Cu compared to Zn, which has a tendency to form tetrahedral Zn chloro-complexes in the presence of chloride ions.

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Concentration together with the stable isotope composition (δ¹⁵N) of both ammonium- and nitrate-nitrogen were conducted for sedentary soils under the piscivorous seabird colony developed on Quaternary basaltic ejecta from the Hatana islands, Fiji, south Pacific. Higher inorganic nitrogen content (up to 2,420 mg-N/kg dry soil) was observed for soils under dense forest vegetation, relative to a lower nitrogen content for soils under sparse grass vegetation (270 mg-N/kg dry soil), reflecting the difference in the mulching effects of vegetative cover for leaching of nitrogen by meteoric water. Active mineralization of uric acid in the bird excreta followed by partial loss due to volatilization of ammonia, nitrification and denitrification were indicated by unique δ¹⁵N values of the inorganic nitrogen as high as +50‰. This unique process was facilitated by high soil surface temperature (24 to 32°C) in combination with the humid tropical climate (annual rainfall: 3560 mm). Distinct isotopic composition of the foliar nitrogen (δ¹⁵N = +13.6 to +36.7‰) indicated acquisition of the inorganic nitrogen derived from bird excreta in soils.

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