Geochemical data presentation

Geochemical data from an urban environment can be elaborated and presented in different ways, depending on the aims of the research project. 

Basically an urban geochemical mapping project should aim to  

Note It is clearly evident that bioavailable concentrations (evaluated through the use of ammonium acetate-EDTA extraction) are significantly lower than aqua regia determined concentrations for the elements considered. N = number 

In many cases not ah the above listed points are taken into account by researchers, depending on their own scientific approaches and specific needs. 

Tijhuis (2003) exclusively chooses soil and sand from kindergartens and playgrounds of Oslo, Norway, as sample materials, aiming much more to evaluate the health risk to children rather than to generate geochemical maps. 

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GIS aided techniques for urban geochemical data presentation 162... 

Spatial interpolation of geochemical data has greatly improved the quality of geochemical data presentation and subsequent interpretation over the past 20 years or so. 

Jurassic—Cretaceous Besshi-type and Mn-Fe strata-bound deposits are present in Hidaka, Hokkaido (Fig. 1.2). Geochemical data and geological evidence all point to a midoceanic ridge environment of ore formation. values of Shimokawa Besshi-type... 

ABSTRACT The results of a soil geochemical survey of the Canadian Maritime provinces and the northeast states of the United States are described. The data presented are for the <2-mm fraction of the surface layer (0-5 cm depth) and C horizons of the soil. Elemental determinations were made by ICP-MS following two digestions, aqua regia (partial dissolution) and a strong 4-acid mixture (near-total dissolution). The preliminary results show that Hg and Pb exhibit elevated abundances in the surface layer, while As and Ni exhibit abundances that can be attributed to the geological provenance of the soil parent materials. 

Presentation of regional geochemical data via Internet Earth browsers Stephen W. Adcock1, Wendy A. Spirito1, Eric C. Grunsky1... 

This paper outlines one approach that is being developed at the Geological Survey of Canada (GSC), where data are extracted from the database and re-cast as KML files that can be displayed in Google Earth or any other KML-aware application. Examples are presented for a recently-completed compilation of till geochemical data from New Brunswick (Adcock et al. 2009). 

Year Three Complete analysis of trace elements by ICP-MS at Lawrence University analysis of major elements by XRF at Macalester College (up to 100 samples) determination of Sr, Nd, and Pb isotopic ratios of a selection of Wolf and Darwin samples by TIMS at Cornell (up to 30 samples). Interpretation of geochemical data, modeling of melting parameters. Presentation of results at Fall AGU meeting by undergraduate student(s). Preparation for fieldwork. 

The distribution of geochemical data may be presented, in their most basic form, through the use of dot maps in which dots, or other symbols selected by the operator, of a size proportional to concentration are plotted at geographical coordinates for each sampled site. Dot sizes may be classified by means of concentration intervals based on percentiles or other statistical methods. Dot maps are often the most suitable method to represent isolated points of a discrete set of geochemical data. 

Comparison of the physicochemical and geochemical data on the forms of transport and conditions of deposition of iron and silica with modern ideas concerning the particulars of sedimentation in the Precambrian makes it possible to evaluate critically and to some extent place constraints on the numerous versions of existing genetic hypotheses. After such reexamination, the scheme of formation for the Precambrian iron-formations that is best substantiated from the physicochemical standpoint can be presented. 

RoUinson H. (1993) Using Geochemical Data Evaluation, Presentation, Interpretation. Longman, Singapore. 

Boninite By boninites, we mean andesites with Ti02 < 0.5 wt.%, plus lavas identified as boninites in the original papers presenting geochemical data (includes some basalts ). 

The data presented in Tables 2-5 are updated as much as possible, with many of the references postdate the late 1980s. Notable exceptions are riverine particulate matter chemistry (Table 2), some references in Table 3, and references concerning the geochemical properties of the six heavy metals discussed in this chapter. There appears to be no recent publication that updates the worldwide average for riverine particulate matter trace metal chemistry (Martin and Whitfield, 1981 Martin and Windom, 1991). This is supported by the fact that two recent references (Li, 2000 Chester, 2000) concerning marine chemistry still refer to this 1981 publication. As for references in Table 3, there is a very limited data available concerning the pathways of heavy-metal transport to lakes. Some of the important works have been considered and... 

Following this result, the total amount of crust recycled by erosion into the mantle would be about 60% of the present crust mass (R 0.6). This is not in conflict with any known geochemical data. An apparent contradiction exists with a maximum value of 30% derived from the mass balance of Ar in the atmosphere and K in the continental crust by Coltice et al. (2000). The argument used by these workers was based on the assumption that the amount of Ar in the atmosphere and the continental crust combined is equal to or greater than that generated over geological time by the amount of K that has ever been in the continental crust by (equation (3)... 

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