Two flameless atomic absorption methods are described for the determination of Hg content and for the identification of Hg forms in rocks, soils and ores; the Ag-trap and the step-heating methods, respectively. In the first method the sample is rapidly heated to 800 °C in 3 min and in the second method the sample is gradually heated to around 900 °C in 30-35 min. In both methods the sample peaks are compared with standard peaks. The method was applied to three mineralization areas - Abergairn, Strontian and Tyndrum. 315 samples were collected at Tyndrum and primary and secondary dispersion patterns of Hg, Pb, Zn and Cu were investigated. The primary dispersion patterns are confined to the fracture zone. Hg is enriched in sphalerite and occurs as HgS and as a lattice-held component. Galena and chalcopyrite are poor in Hg. A study of the geochemistry of mercury in different soil horizons has revealed that widest anomalies are obtained with samples of the -0.063 mm fraction of soils from B horizon. HgS is the predominant phase of mercury in the soils with an increasing importance over the ore zone. Organic matter is the chief adsorbing medium whilst clay minerals are unimportant. 1316 rock samples were collected over an area of 230 km2 in the Cairngorm granite. The importance of sample size and in-situ variance are discussed. The mercury patterns are presented as a contour map. The granite is remarkably low in Hg (average 6 p.p.b.) which is distributed uniformly in most areas. Micas contain the highest concentration of Hg followed by feldspars and quartz. Mercury is not associated with pegmatite veins. In all the samples Hg is predominantly held in the lattices of rock forming minerals but small amounts of HgCl2 and HgS are found in the anomalous samples. The granite is also low in Zn and Cu. Although the studied areas occur in a Hg-poor province mercury appears to be a useful pathfinder element in the search of sulphide mineralization. The ease of analysis and also the potential of the thermal release technique together with chemical manipulation of samples are the obvious advantages of mercury.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:593859 |
| Date | January 1978 |
| Creators | Yaliz, Aykut |
| Publisher | University of Aberdeen |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU441477 |
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