Geochemical studies

Geochemical studies of sulfate ia streams have beea approached ia various ways. For example. Ref. 17 is a review of Hterature oa sources of sulfate ia the dissolved loads of streams, especially ia areas where developmeat effects are likely to be stroag. It was coacluded that for North America as much as 60% of the average yield of sulfate carried to the ocean is related to human activities. This study assigned a higher proportion of the total yield of sulfate ia European streams to human sources, but for other continents it was thought the effects of human activities to be relatively minor. 

A collision with a Mars-sized object may have resulted in the formation of the Earth s moon. Our moon is by no means the largest satellite in the solar system, but it is unusual in that it and the moon of Pluto are the largest moons relative the mass of the planets they orbit. Geochemical studies of returned lunar samples have shown that close similarities exist between the bulk composition of the moon and the Earth s mantle. In particular, the abimdances of sidero-... 

A large number of geochemical studies on Kuroko deposits (fluid inclusions, gas fugacities, chemical and isotopic compositions of ore fluids etc.) have been carried out. These are summarized below. 

Marumo, K. (1989) Genesis of kaolin and pyrophyllite of the Kuroko deposit of Japan Mineralogical and geochemical studies. Geochim. Gosmochim. Acta, 53, 2915—2924. 

Takahashi, K. (1963) Geochemical study on minor elements in sulfide minerals. Geol. Surv. Japan Kept., 199, 1-69 (in Japanese). 

The above summarized mineralogical and geochemical studies on Kuroko and Mariana chimneys (Shikazono and Kusakabe, 1999), and previous studies on midoceanic ridge chimneys, combined with the studies of mineral particle behaviors in the plumbing system, are used to develop the following plausible model for the growth history of sulfate-sulfide chimneys on the seafloor (Shikazono and Kusakabe, 1999). 

Kase, K. and Yamamoto, M. (1985) Geochemical study of conformable massive sulfide deposits of the Hitachi mine, Ibaraki Prefecture, Japan. Mining Geology, 35, 17-29. 

Frequently, many laboratories around the world are joint participants in major geochemical studies. One example already mentioned is the lunar program of almost... 

Modern geochemical studies use data for a much larger suite of elements, determined at much lower concentrations, to model the tectonic movements of continental plates, and to understand the sources of magma generated in that process (e.g. Lightfoot 1993 Sutcliffe 1993). The key elemental suites include the incompatible ... 

Condomines M, Morand P, Camus G, Duthou JL (1982a) Chronological and Geochemical study of lavas from the Chaine des Puys, Massif Central, France evidence for crastal contamination. Contrib Mineral Petrol 81 296-303... 

Miller, R. N. "A Geochemical Study of the Inorganic Constituents in Some Low-Rank Coals, Ph.D. Thesis, Pennsylvania State University, 1977, 314 pp. 

Rn-220 is another isotope of radon and belongs to the thorium decay series. Due to its short half life of 55.6 s, reports on its concentrations in those gases and in natural water are still scant. They are also important for a better estimate of our exposure to natural radioactivity and also for the geochemical study of the forma tion of those radon isotopes and their underground movement. 

Iwasaki, I., Geochemical Studies of the Tamagawa Hot Springs, Onsen Kagaku (Journal of the Balneological Society of Japan) 14(2) 27-37 (in Japanese) (1959). 

Malcolm RE, Vaughan D (1979) Effects of humic acid fraction on invertase activities in plant tissues. Soil Biol Biochem 11 65-72 Malcolm RL (1989) Application of solid-state 13C NMR spectroscopy to geochemical studies of humic substances. In Hayes MHB, MacCarthy P, Malcolm RL, Swift RS (eds) Humic substances II. In search of structure. Wiley, Chichester, UK, pp 339-372... 

One of the most useful implementations for geochemical modeling, published by Harvie et al. (1984), is known as the Harvie-Mpller-Weare (or hmw) method. The method treats solutions in the Na-K-Mg-Ca-H-Cl-S04-0H-HC03-C03-C02-H2O system at 25 °C. Notably absent from the method are the components Si02 and Al+++, which are certainly important in many geochemical studies. There is, in fact, no published dataset regressed to include virial coefficients for both silica and aluminum. 

Neutron activation analysis is an attractive method in many trace element problems, or where the total amount of sample is limited. Many geochemical studies of trace constituents and semi-conductor developments have used the technique, whilst in recent years pollution investigations have provided a new focus. In forensic science small flakes of paint, single hairs and a variety of other small samples have been analysed and identified by activation analysis. In recent years activation analysis has lost further ground to ICP-MS which provides more comprehensive information and is more readily operated. Sensitivity is also comparable in many cases. 

Geochemical studies by Hughes (1988), Ericson Glascock (2004), and Drucker (2007) employing multivariate statistical analysis have delineated major obsidian sub-sources within the CVF. This study was undertaken to ascertain the extent which LIBS could be applied to the problem of obsidian sourcing through analysis of the same suite of samples that was analyzed by Draucker (2007). 

Lech, M. Caritat, P. de 2007. Regional geochemical study paves way for national survey - Geochemistry of near-surface regolith points to new resources. AusGeo News, 86. 

Surficial geochemical studies in support of non-renewable mineral resource assessments, Northwest Territories, Canada... 

Michel, H. V., Asaro, F., Alvarez, W. Alvarez, L. W. (1990). Geochemical studies of the Cretaceous-Tertiary boundary in ODP holes 689B and 690C. Proc. ODP Sci. Res.,... 

Rowlett, S.M. (1980) PhD Thesis. Geochemical Studies of Recent Sediments from Cumbria, UK, University of Liverpool. 

Equations 1.113 and 1.114 are the most frequently used in geochemical studies. However, the most physically sound equation of state for solids is perhaps the Born-Mayer form ... 

Following my appointment to the Department of Geology in September 1968 rock geochemical studies were undertaken on five Palaeozoic Zn-Pb (Cu) massive sulfide deposits in northern New Brunswick. A total of 115,000 analyses were performed on 13,000 rock samples from the environs of the Heath Steele B and ACD zones, BMS (Brunswick Mining and Smelting) No. 12, Caribou and Key Anacon sulfide deposits. In all cases significant anomalies were defined. 

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