Hyperspectral reflectance in mineral exploration: example from the Northwest Zone of the Lemarchant VMS deposit, Newfoundland, Canada

Hyperspectral reflectance spectroscopy hasbeen widely available for more than 25 years and is nowundertaken as a standard procedure by many explorationand mining companies. The data collected is used tocharacterize the mineralogy of alteration zones but is rarelyused in conjunction with geochemical...

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Bibliographic Details
Main Authors: Cloutier, J, Piercey, SJ
Format: Conference Object
Language:English
Published: Society for Geology Applied to Mineral Deposits 2017
Subjects:
Online Access:https://numerique.banq.qc.ca/patrimoine/details/52327/3081324?docref=SEuN9eSXUE9JiKJ5YXbZ7g
http://ecite.utas.edu.au/142385
Description
Summary:Hyperspectral reflectance spectroscopy hasbeen widely available for more than 25 years and is nowundertaken as a standard procedure by many explorationand mining companies. The data collected is used tocharacterize the mineralogy of alteration zones but is rarelyused in conjunction with geochemical datasets. In thisstudy, we integrate hyperspectral and whole rockgeochemical datasets acquired at the Northwest Zone ofthe Lemarchant volcanogenic massive sulfide (VMS)deposit in order to determine the dominant formationprocesses and to establish new exploration parameters.The mineralization at the Northwest Zone is hosted inandesitic and dacitic rocks and exhibits intensehydrothermal alteration (e.g., high CCPI, AI and Ba/Srlithogeochemical signatures) extending at least 300 malong strike of the andesitic and dacitic units. The alterationcorridor has hyperspectral signatures that correlate withphengitic white micas with 2200W longer than 2215nm, andMg-rich chlorites with 2250W shorter than 2252nm. Theintegration of hyperspectral reflectance, geochemicalalteration proxies (i.e., AI, CCPI, Ba/Sr, NA 2 O) and massvolume changes has documented specific alterationprocesses responsible for the alteration (i.e., seawateralteration versus silicification), which is not possible usinghyperspectral reflectance or geochemistry alone.