Pathfinder element

New exploration techniques, and new reference materials in support of them, were needed. One major change was in the use of ore pathfinder elements, rather than the ore elements themselves, for exploration purposes. For example, instead of analyzing samples for the primary Au ore element, samples were analyzed for As, Hg, and W pathfinders that pointed to hidden gold deposits. The pathfinder elements occur in association with ore veins, but have a much broader spread than the mineralized area itself. However, measurement of the pathfinder elements requires methods with better detection limits than were needed in earlier exploration programs, as the pathfinders typically are not as enriched as the ore elements, in comparison to baseline crustal levels. 

Also consider the use of NIST sediments 1646, 2704, and soils 2709-2711 in exploration geochemistry. These samples were certified largely in view of the demand for samples to support monitoring of toxic elements in environmental samples. However, many of the elements certified overlap either the list of primary ore elements or the list of pathfinder elements. Thus, these samples may legitimately be used in a very different application than the one that prompted certification. The sample matrix is ideal for the alternative application, and so is the suite of certified elements. 

The partial leach results from soil samples identify the location of the buried Honerat kimberlite. The depletion of Ni, Mg, Co, K, and total REEs in C-horizon soils over the Honorat kimberlite suggests that numerous kimberlite pathfinder elements are not adsorbed on to soil particles. Instead, they are remaining in the dissolved phase in solution due to the more reducing environment inside... 

Kimberlite bodies can be identified at ground surface using soil geochemistry where 90 m of glacial sediment overlies a kimberlite. This is based on variations in element concentrations of pathfinder elements such as Ni, Mg, Co, K, and total REEs over versus off a kimberlite. 

Mobile, on-line XRF methods have been tested in the Au exploration targets. Analysis of continuous till and weathered bedrock samples shows clear variation of the contents of pathfinder elements of hydrothermal alteration. Particularly, in the weathered bedrock, the presence of narrow mineralized veins is seen (Fig. 5). One interesting feature is that the indication of the weathered bedrock sources can be traced 2 to 5 m down-ice in the till. These results suggest very short glacial transport of mineralized debris from the bedrock sources. Information on... 

Brondi M, Dall Aglio M, Vitrani F (1973) Lithium as a pathfinder element in the large scale hydrogeochemical exploration for hydrothermal systems. Geothermics 2 142-153 Brooker R, Blundy J, James R (2000) Subduction-related mantle pyroxenites from Zabargad Island, Red Sea. J Conf Abst 5 249... 

Follow-up ground studies involved the analysis of outer bark from western hemlock collected at 100 m sample spacing over the Tl anomaly south of Tsuius Creek. This permitted more clearly defining the extent of the Tl anomaly (600 m X 600 m) and its relationship to other trace elements. Figure 1 shows the Tl anomaly and the spatial relationship of Hg which appears to define a conjugate set of lineaments interpreted as leakage from structural weakness. The multi-element association at this locality suggests that Tl and Hg may be pathfinder elements to concealed base-metal mineralization. 

Keywords indicator minerals, till geochemistry, pathfinder elements, Ni-Cu exploration... 

A preliminary interpretation of both new and historical surface rock and soil geochemical data suggests that Au, As and Sb are the most effective pathfinder elements in the supergene environment and that extensive secondary dispersion haloes can be recognized. Base metals, which are only rarely enriched in wallrocks within primary alteration haloes (Arne et al. 2008), correlate with Fe and Mn in weathered material due to scavenging. 

The soil orientation survey consisted of three east-west traverses across the known areas of mineralization on the property at Pico Prieto and Venado and three soil profiles in the Venado area. The primary purpose of the soil traverses was to determine the spacing required to find a deposit of similar dimensions and style of mineralization, and to determine the optimum soil size fraction and pathfinder elements for these styles of mineralization. The purpose of the soil profile samples was to determine whether metal concentrations vary with soil horizon and depth. 

Geochemical detection of uranium deposits in sandstone-type deposits depends on the geochemical behavior of U and pathfinder elements (Rose Wright 1980). Uranium is dispersed under oxidizing conditions but is immobile under reducing conditions. Adsorption on freshly precipitated Fe-oxides and certain types of organic matter also limits dispersion unless high concentrations of or... 

PATHFINDER ELEMENT, An element present in small proportions less than 1 % generally metallic in nature, associated with ore deposits at the time of formation. Mapping of the concentration variation of the selected element serves to locate the main ore deposit Examples are zinc as the pathfinder for lead, copper, and silver ores, and molybdenum associated with copper deposits. 

Shiikawa, M. (1983) The role of mercury, arsenic and boron as pathfinder elements in geochemical exploration for geothermal energy. Journal of Geochemical Exploration, 19, 337-38. 

Arsenic in prospecting, mining, and markets 5.8.1 Arsenic as a pathfinder element in prospecting... 

Pathfinder element In ore prospecting, a relatively mobile, common, and easy to identify element in soils, sediments, rocks, or plants that may provide information on the location of a less common and more valuable element. Arsenic is sometimes a pathfinder element for gold. 

The rationale for using Hg as a pathfinder element in mineral exploration is attractive. Because of its volatility, Hg is presumed to form broader halos in the hypogene environment than most elements. It is envisaged that both vapour-phase and solution transport are responsible for a wide dispersion of the element. In the secondary environment it is well known that Hg exerts a measurable vapour pressure at ambient temperatures and possesses redox properties that allow the metal to exist in the elemental state under a range of natural conditions. Therefore it has been claimed that, as a host sulphide-body weathers, it can be expected that Hg will be converted partly to the vapour state, thereby overcoming the constraint of hydromorphic or solution dispersion that applies to other target and indicator elements. Vapour-phase dispersion through permeable rock or cover would allow Hg to be detected in soil or soil gas, and perhaps as an atmospheric anomaly. 

There are a number of well-documented examples of the use of Hg vapour related to geothermal studies (e.g., Phelps and Buseck, 1978 Shiikawa, 1983 Openshaw, 1983 Zhu et al., 1986). In many of these Hg, together with the volatile elements As and B, are shown to be useful pathfinder elements in geochemical exploration for geothermal resources. 

Because of its almost universal association with porphyry copper deposits and its mobility characteristics. Mo has been used extensively as a pathfinder element for geochemical prospecting for porphyry copper deposits (Rose, Hawkes, and Webb, 1979). Dispersion of Mo in mineralized areas has been shown to occur by both hydromorphic (Bradshaw, 1974) and mechanical (Hansuld, 1966) processes. 

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