Development of cost effective surface geochemical methods is a real challenge to regional exploration for new large and giant deposits in diverse overburden terrians. New geochemical methods——NAMEG (collection of nanoscale metals in earthgas) and MOMEO (leaching of mobile forms of metals in overburden) have been developed. These two methods have been widely investigated for their usefulness and suitability for strategic reconnaissance surveys with wide spaced sampling for delineation of broad geochemical patterns generating from concealed giant ore deposits.Encouraging results have been obtained. (1) Large regional anomalies occur across large and giantore deposits or metallogenic belts. Methods focused on them can be used to delineate strategic targets for the discovery of giant ore deposits. (2) The methods give a significant response to deep seated mineralization at a depth of over 300 meters. The cover does not mask the mineralization indicators. (3) Use of both methods can obtain more reliable information generated from the deep buried mineralization. (4) MOMEOmethods can be used to estimates the quantity of metals available for mineralization. (5) These new techniques can significantly reduce the geophysical and drilling costs.
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