Elements, geochemical

K. K. Turekian, Elements, geochemical distribution of, McGraw Hill Encyclopedia of Science and Technology, Vol. 4, pp. 627-30, 1977. 

KEYWORDS acid-mine drainage, trace elements, geochemical modeling... 

Multi-element geochemical mapping in Southwest China Zhizhong Cheng1 Xuejing Xie1... 

KEYWORDS 76 elements, geochemical mapping, analytical scheme,... 

CRMs were inserted into the approximately 3000 samples in the 76-element geochemical mapping pilot project in southwestern China. The RSD% of these determinations and the certified values are listed in Table 3. All the RSD are less than 25% and the analytical data are considered accurate. Data accuracy had also been subsequently justified from the mapping results. 

ABSTRACT Southwest China s 76 elements geochemical mapping project was initiated in 2000. 2700 composite samples from the 1000,000 RGNR supplement samples were prepared. The 76 elements analytical system using modern analytical instruments such as ICP-MS, XRF, ICP-AES as backbone, supplemented with other techniques was estabished. The geochemical maps provided the distribution of all the elements in the periodic table. 

The 76 elements geochemical maps show the distribution of all elements in the periodic table, especial for rare and dispersive and precious metals elements. 

Elements chosen from the limited NURE multi-element geochemical packages that may be pathfinders for porphyry-style deposits (Lefebure Ray 1995) include Ba, Co, Cu, Mn, Pb, Ti, V, and Zn. Under the NURE program, two analytical techniques were used energy dispersive x-ray fluorescence (Cu and Pb) and neutron activation (Ba, Co, Mn, Ti, V, and Zn). Single element plots and element association plots were generated. Geochemical data for pond sediments collected over the Pebble deposit in 2008... 

Trace element geochemical values for the Williams Brook project were obtained... 

Figs. 3-6. Gold and trace element geochemical concentrations with depth In DDH-WB-08-04. Values are not corrected for mass loss or gains. Higher values of Cu, Zn and As exist In the mudstones underlying the rhyolites In hole WB-08-04. 

Stanley, C. R., and Sinclair, A. J. (1987). Anomaly recognition for multi-element geochemical data— A background characterization approach. J. Geochem. Explor. 29, 333-351. 

Historically, analysis for selenium has been difficult, partly because environmental concentrations are naturally low. Indeed, selenium analysis still remains problematic for many laboratories at concentrations below 0.01 mg a relatively high concentration in many environments (Steinhoff et al., 1999). Hence, selenium has often been omitted from multi-element geochemical surveys despite its importance (Darnley et al., 1995). Analytical methods with limits of detection of <0.01 mgL include colorimetry, total reflectance-XRF, HG-AFS, gas chromatography... 

Studies of Sr, Pb and Nd isotopes, coupled with trace-element geochemical studies, have shown that the source regions of many continental alkaline volcanics have been enriched in LIL elements, generally some hundreds of million years prior to the beginning of volcanism, and enrichment has been interpreted as due to mantle metasomatism.It has been suggested that mantle metasomatism is a necessary precursor to alkaline continental volcanism.Alkaline rocks erupted in oceanic environments, and even ridge tholei-ites, sometimes bear evidence of source enrichment, which has been interpreted as a result of mantle metasomatism. ... 

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