Use of blasthole assay results for structural interpretation at Lone Tree mine, Humboldt County, Nevada; U.S.A.

摘要

The Lone Tree mine, a structurally controlled golddeposit in Palaeozoic-age sedimentary rocks of north-centralNevada, is a good example of where blasthole assay results can beused to delineate details of structural features that might not beevident from periodic pit mapping. The Powerline fault, anorthtrending compound fault zone, is the most important ore hostat Lone Tree. The close association of ore-in particular, higher-grade material (>3 ppm gold)-with brecciation in the fault zoneallows significant structural interpretations to be produced fromthe outlines of higher-grade ore obtained from blasthole assayresults. The location, morphology and internal structure of thePowerline fault, including such features as fault segments,stepovers and internal horses, can be recognized when geologicalpit mapping is combined with the 4-m spacing of blasthole assay results.