Showing papers in "Chemical Geology in 1978"

TL;DR: In this paper, a series of immobile-element diagrams for metamorphic volcanic suites is presented, based on geochemical data on meta-volcanic suites in the greenschist, amphibolite and granulite facies.

TL;DR: In this article, it is suggested that massive mixing processes occur near the base of the continental crust when mantle magmas are ponded near the Moho interface and this process is responsible for the general geochemistry of granitic magmas.

TL;DR: In this paper, the equilibrium solubility of mixed-valence Mn oxides was analyzed and four graphs were summarized in four graphs for Co, Pb, Ni and some other elements.

TL;DR: In this paper, rare earth element (REE) distributions in individual eruptive basaltic units from eastern Iceland, Mull and the Mid-Atlantic Ridge are presented in order to determine the mobility of these elements during hydrothermal alteration.

TL;DR: In this article, samples of pyrite, chalcopyrite and pyrrhotite were subjected to 52°C and 68% Relative Humidity in air for periods of up to four weeks.

TL;DR: In this paper, the relationship between F and Co2−3 in the carbonate-fluorapatite, on a mole basis, indicates that CO 2−3 substitutes for PO3−4 on a one to one basis.

TL;DR: The concentrations of the major substitutents Na, Sr, CO 3 and SO 4 in the carbonate phase of marine sedimentary phosphorites show large systematic variations between, and within, deposits now on land, whilst variations are minimal between or within, present sea-floor deposits as discussed by the authors.

TL;DR: In this article, it was shown that the addition of 1 mole% P 2 O 5 plus 3 mole% TiO 2 to melts in the system fayalite-leucite-silica causes a marked expansion of the two-liquid field towards K-rich compositions.

TL;DR: In this paper, the geochemistry of acid, sub-acid metamorphic rocks of sedimentary origin from a sequence of increasing metamorphism of the Western Italian Alps has been studied.

TL;DR: In this paper, the authors analyzed granitic plutons from New Mexico for major and trace elements and classified them into four groups: high-Ca, high-Si and high-K, and trondhjemite.

TL;DR: In this article, chemical and isotopic analyses for thermal brines from three springs and two boreholes on the Reykjanes peninsula are presented for D and 18O analyses, which suggest that the discharge waters are formed mainly by the penetration of local meteoric water into brine-bearing formations followed by evaporation of this brine.

TL;DR: In this article, a new fusion method using lithium metaborate, suitable for the determination of major and trace elements by X-ray fluorescence analysis (XRF), has proven to be of comparable accuracy to other XRF methods for the ten major rock-forming oxides.

TL;DR: In this paper, a log-linear relationship at low Na concentrations and converges toward NaHCO 3 saturation at higher concentrations was investigated at 25°C, pH's between 6.8 and 8.4 and aqueous Na + concentrations between 5·10 −4 and 2 M.

TL;DR: In this paper, the same kerogen-like residue from the algal mats and oozes at Laguna Mormona, Baja California, is examined following degradation by saponification, alkaline KMnO4 oxidation, and HBr treatment.

TL;DR: In this article, the elements Os, Ru and Ir have been determined in fifteen chromites from nine different Greek localities and the examined chromites show a relatively homogenous distribution of the above elements, which also exhibit a pronounced linear correlation compared to each other.

TL;DR: In this article, element mobility during palagonitization of an Icelandic subglacial hyaloclastite of olivine tholeiitic composition has been studied and the ranges of percent losses in concentration per volume of oxides when sideromelane alters to palagonite, were found to be: SiO2 29−49; Al2O3 17−32; TiO2 37−58; FeO 65−91; total Fe as Fe2O 3 24−40; MgO 4−71; CaO 58−85

TL;DR: The isotopic composition of the brines in Lake Vanda and Taylor Vanda has been studied in this article. But the results of these studies were limited to the water in the lake and not to the brine in the surrounding basins.

TL;DR: A variety of lipid classes analysed in a core from an intertidal, tropical algal mat (Abu Dhabi, Persian Gulf) show little or no evidence of a higher-plant contribution and are compatible with the most abundant micro-organisms identified in the core.

TL;DR: In this paper, it was shown that peloidal oolitic sand-size grains composed basically of Fe oxides are transformed into the Fe(III)-smectite nontronite in sediments of Lake Chad.

TL;DR: In this article, a detailed investigation of synthetic ooid formation in solutions containing humic and fulvic acids shows that this ability does not parallel the extent to which the organic matter is sorbed by carbonate surfaces, but is related to a specific type of organo-carbonate interaction involving the formation of organic membranes.

TL;DR: In this paper, the ionic compositions of the davidite and euxenite-polycrase are derived from the analyses and compared with the ideal formulae, and a modified technique for synthetic glass formation is presented.

TL;DR: In this article, the partition coefficient of Sr between gypsum and solution was determined as 0.21 ± 0.01 at temperatures between 20 and 60° C at seawater evaporation.

TL;DR: The Saguenay River and Fjord comprise part of the St. Lawrence drainage basin of eastern Canada and high levels of total Hg occur in the sediments (0.25 −218 mg kg−1), in suspended particulate matter (1 −50 mg kg −1), and in water (0.,07 −0.38 μg 1−1) as mentioned in this paper.

TL;DR: The Megacryst Tuff Formation at the Aljustrel mining centre in southern Portugal belongs to the Volcanic-Siliceous Complex, the pyritite-bearing sequence of low-grade meta-morphic volcanic tuffs and sediments in the southwestern Iberian peninsula as mentioned in this paper.

TL;DR: A bitumen sample from the base of the Windy Knoll deposit has been examined by qualitative and quantitative reflected-light methods and by X-ray diffraction techniques as discussed by the authors.

TL;DR: In this article, a suite of granitic partial melts and their residual parent gneisses were analyzed for rare-earth element (REE) analyses, and it was shown that the behavior of REE in the suite studied (Eu excepted) is almost entirely controlled by minor minerals (other than refractory zircon and apatite) which have very large crystal/melt partition coefficients for the REE.

TL;DR: In this paper, complex mixtures of sulfur compounds were readily produced from the reaction of ethylbenzene and sulfur in laboratory experiments under mild thermal conditions, and eight compounds were produced and identified in the product mixtures.

TL;DR: In this paper, the relative importance of temperature, pressure, presence/absence of soluble lipids and nascent atmospheric conditions on generated products was evaluated in a series of laboratory experiments in order to evaluate relative importance.

TL;DR: In this article, a method for the determination of iodine in natural waters, rocks, soils and plant material is described, based on the Sandell-Kolthoff reaction, using the catalytic action of iodine on the reaction between As 3+ and Ce 4+ and has been adopted for use with the Technicon® autoanalyzer.

TL;DR: Dostal et al. as discussed by the authors studied the geochemistry of the Savalan volcano and found that the major and trace element content of the rocks is consistent with the derivation of their parental magma by partial melting of upper-mantle garnet peridotite enriched in large-ion-lithophile elements (LILE) and presumably located in the region overlying the subduction zone.