Jerritt Canyon is hosted by silty carbonate or carbonaceous siliciclastic
rocks originally deposited as shelf sedimentary rocks during the Paleozoic age. The Paleozoic host rocks have been imbricated, faulted, and folded through several orogenic events in the Paleozoic and Mesozoic. An early phase of intrusive igneous
activity is represented by west-northwest mafic igneous dikes of Paleozoic age.
Carlin-type gold deposits were emplaced
during the Middle to Late Eocene during an initial phase of extensional tectonics at which time high potassium calc-alkaline magmatic rocks were emplaced. Mafic and intermediate igneous dikes were emplaced during this phase of igneous activity and
demarcate north-northeast-oriented structures. The primary controls on the occurrence, distribution, and form of the deposits are:
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Favourable host rocks (formation units)
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The reactivation of Paleozoic and Mesozoic structures
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Eocene syn-mineralization normal faults
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In general terms, the intersection of structures with favourable host rocks is the primary control and the form of
mineralization ranges from apparently stratabound to fault hosted where the faults can be either highly discordant to bedding or bedding-parallel. Deposits at Jerritt Canyon are mostly stratabound or fault hosted. Gold occurs as very fine, micron
sized, particles in pyrite and arsenian pyrite. Other sulfides are orpiment, realgar, and stibnite. Alteration includes carbonatization, decalcification, and silicification (jasperoid).
Exploration
Exploration
completed by JCG has included desktop compilation and interpretation of historical datasets, target identification, and reverse circulation (RC) and core drilling. Drilling completed at Jerritt Canyon by JCG includes two phases of
surface drilling and on-going underground drilling. In the fall of 2015, JCG initiated a comprehensive compilation of all historical geophysical data for Jerritt Canyon as well as a compilation of past surface geochemistry including soil, stream
sediment, and bedrock sampling, completed to 2015. Interpretation of these compilations incorporated geology, gold distribution, and past surface exploration drilling and resulted in the identification of exploration targets and development of a
surface RC exploration program, which was executed in the fall of 2016.
In early 2017, JCG commissioned further detailed
evaluation of the historical gravity data, inversion and examination of DIGHEM EM and magnetic data, inversion and examination of the ground magnetic data, and examination of the Titan survey results.
In the spring of 2017, JCG commissioned Goldspot Discoveries Inc. (Goldspot) to complete a machine learning
(AI) compilation, interpretation, and targeting study. The 2017 study incorporated several datasets from Jerritt Canyon including drilling (lithology and assay), surface geology, topography, soil geochemistry, gravity, DIGHEM EM, magnetic, and
radiometric data. Goldspot incorporated hyperspectral data into the compilation and interpretation. Based on the 2017 study, Goldspot generated target areas, planned drill holes, and completed a 3D geological model incorporating structural and
lithological information in Leapfrog software.
Drilling
Starting January 1, 2015 through December 31, 2020, JCG has drilled a total of 18,533 holes between RC and core from
underground drilling sites, comprising of 2,800,695 ft of drilling.
Mineral Resources Estimate
Since the completion of the RPA, 2018, Technical Report on the Jerritt Canyon Mine, Elko County, Nevada, USA (September
28, 2018), JCG has conducted in-fill drilling programs from the surface and
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