Showing papers in "Chemical Geology in 1987"

TL;DR: In this paper, the authors report analyses of O, Sr, Nd and Pb isotope ratios in 52 fresh glasses of mid-ocean ridge basalt (MORB).

TL;DR: In this paper, the homogenization temperatures of the synthetic fluid inclusions were analyzed by micro-thermometry, and the results of these experiments compare favorably to previously published ones; however, they do not consider solutes containing more than one solute.

TL;DR: Two classes of procaryotic organisms were cultured on specific inorganic and organic nitrogenous substrates and the application of the coupled separation-isotopic analysis of amino acids yield a better understanding of comparative biochemistry for these organisms.

TL;DR: In this article, the results of electron microscopy, selected-area electron diffraction and energy-dispersive X-ray spectroscopy point analyses were obtained from Lower Moose Lake in the Onaping region near Sudbury, Canada.

TL;DR: In this article, the authors analyzed REE (rare-earth elements) and mineralogy of stream sediment derived from plutonic, metamorphic, or mixed pluton-metamorphic sources in the Wet Mountains, Colorado.

TL;DR: The average sedimentation rate of Greifensee has been evaluated by using varve counting and 210Pb and fallout radionuclide dating from 4 different sites in the lake, to amount to 0.14 ± 0.02 g cm−2 yr.−1.

TL;DR: K-Ar dating of a set of flood basalts from eastern India indicates that volcanism ∼ 115 Ma ago was much more voluminous than heretofore recognised, covering an area of at least 2·105 km2 as discussed by the authors.

TL;DR: In this paper, the use of loss on ignition (LOI) in whole-rock analysis is evaluated in the modern context, as a measurement of total volatiles, mainly added to the other oxides to assess analytical accuracy by testing whether or not the total is 100.0 ± − 1.0%.

TL;DR: In this paper, chemical and physical observations are presented to explain the evolution of stream water chemistry along the flow path in Warm River Cave and Falling Spring Creek, showing that the water is supersaturated with respect to CO2 both in the subsurface and at the surface of the Earth.

TL;DR: In this paper, a new set of partial molar heat capacities has been derived for 11 oxides of geochemical interest for the temperature interval 273-1200 K, and a simple procedure is proposed to calculate C P g for glasses containing other oxides.

TL;DR: In this article, a multichannel detection system was proposed for fluid inclusions of laser-excited Raman micro-spectrometry with a multi-channel detection system.

TL;DR: In this article, the geochemistry of lateritic terrains is discussed in terms of nutrient demand in agriculture and the data presented show a dramatic depletion of virtually all nutrients when compared to crustal levels and other soil systems, and replenishment of the laterite to the nutrient levels of natural fertile soils can be basically attained by adding into the system ground rocks of varied composition.

TL;DR: Watson et al. as mentioned in this paper showed that Hf is more compatible in clinopyroxene than are the heavy rare earths in the suboceanic mantle than is Pb, and in doing so reemphasize the paradox surrounding the poor correlation of U/Pb with Rb/Sr and Nd/Sm in mid-ocean-ridge basalts.

TL;DR: In this article, a systematic mapping of crustal fluids using fluid inclusion analysis has been carried out for the Variscan basement and the overlying Permo-Mesozoic sedimentary cover in the Federal Republic of Germany.

TL;DR: In this article, the rare-earth element (REE) distribution in uraninites from a variety of hydrothermal mineral deposits is analyzed and it is shown that wide variations are to be anticipated.

TL;DR: The effect of foreign ions on the dissolution kinetics of calcite was studied in this article, where it was shown that the effect of ion strength, ion-pairing and the common-ion effect on calcite dissolution is negligible.

TL;DR: The post-Variscan vein mineralization in the Federal Republic of Germany is characterized by highly saline fluid inclusions (Te < −52°C, Tmice ∼ −26° to −20°C and Th <200°C) as mentioned in this paper.

TL;DR: In this paper, a review illustrates that relatively rapid weathering of finely comminuted volcanic ash well reflects the effects of climate, vegetation and time, and produces various combinations of weathering products.

TL;DR: In the field of petrology, the relevance of phreatomagmatism is realized increasingly because it takes place in many diverse environments and affects not only small monogenetic volcanoes but also large volcanoes.

TL;DR: In this article, it is inferred that the silicate/sediment contribution ratio of the world-average rivers to seawater Sr changes at a very slow rate, and that the seawater 87 Sr 86 Sr secular main trend over the Phanerozoic is controlled by hydrothermal alteration of oceanic basalts and slow variation of the limestone/silicate contribution ratio to the riverine Sr.

TL;DR: A method for the measurement of dissolved water in crushed and sieved volcanic glasses utilizing Karl-Fischer titration and sample pyrolysis without the addition of a flux was described in this paper.

TL;DR: Ion microprobe analysis offers high spatial resolution (10 μm) and low detection limits for many elements in calcite Detection limits are likely to be instrument dependent; the values given here are specific to the instrument used (a modified AEI-IM® 20) and more recent instrument designs should give lower detection limits.

TL;DR: In this paper, the geochemical evolution characterized by a strong depletion of Ca and Mg in solution and an increase in alkalinity and pH is confirmed as the dominant process governing the formation of soda alkaline lakes.

TL;DR: Samples collected by dredge hauls and submersible dives from the New England Seamount (NES) chain, the most prominent of six seamount groups in the Northwest Atlantic Ocean, have been analyzed for Sr, Nd and Pb isotopic compositions and rare-earth and other trace-element contents as mentioned in this paper.

TL;DR: In this article, a locally derived organic water origin is proposed where both hydrogen and carbon were derived from organic constituents such as petroleum during bacterial sulphate reduction reactions, with the carbonate carbon being derived from the organic carbon.

TL;DR: In this paper, the sediment-depth distributions of 238Pu, 239,240Pu and 241Am have been measured in a sediment core from the Saguenay Fjord, Quebec, Canada, which has been dated to better than 1-yr. resolution over the past 100 yr using 210Pb.

TL;DR: In this paper, the effect of a small igneous intrusion on Rundle oil shale was evaluated using a range of techniques, including X-ray diffraction, thermal and isotopic analyses, gas chromatography-mass spectrometry, electron spin resonance, nuclear magnetic resonance spectroscopy and demineralizing techniques.

TL;DR: In this article, the means of extracting and quantitatively analyzing volatiles in fluid inclusions have been studied and details of the methods developed are presented. But the main focus of this paper is on the extraction and quantification of inclusions.