Publication Type:

Journal Article

Authors:

Poulin, Rémy S.; McDonald, Andrew M.; Kontak, Daniel J.; McClenaghan, M. Beth

Source:

The Canadian MineralogistThe Canadian Mineralogist, Mineralogical Association of Canada, Ottawa, ON, Canada, Volume 54, Number 5, p.1147-1173 (2016)

ISBN:

0008-4476

Keywords:

Abitibi County Quebec, Asia, British Columbia, Canada, Cathodoluminescence, Central Europe, chemical composition, Commonwealth of Independent States, copper ores, crystal chemistry, Czech Republic, eastern canada, electron microscopy data, Europe, Germany, gold ores, greisen, ICP mass spectra, igneous rocks, Kyrgyzstan, laser ablation, laser methods, mass spectra, massive deposits, massive sulfide deposits, metal ores, metals, Metamorphic rocks, metasomatic rocks, mineral deposits, genesis, molybdenum ores, porphyry, PORPHYRY COPPER, porphyry gold, porphyry molybdenum, quebec, rare earths, Scheelite, SEM data, skarn, spectra, tungstates, tungsten ores, Val d'Or Quebec, volcanic rocks, Western Canada

Abstract:

The relationship between cathodoluminescence (CL) response and chemical composition of scheelite from a variety of ore-deposit settings (e.g, orogenic Au, skarn, porphyry-related, greisens, VMS) was investigated using SEM-EDS, CL imaging, and LA-ICP-MS techniques. Our detailed study concentrates on five samples of scheelite from a range of ore-deposit settings, including orogenic Au, skarn, VMS, and greisen deposits, but draws on a yet unpublished data base of more than 39 deposits world-wide. Results indicate that the scheelite zonation patterns observed under CL can be useful in discriminating between scheelite arising from differing mineralized environments. Scheelite from orogenic Au deposits exhibits a homogenous CL response in contrast to that from proximal intrusion-related systems, such as porphyries, skarns, and greisens that show a strong oscillatory zonation, with individual zones ranging from 300 mu m in width. Results from LA-ICP-MS analyses show significant chemical variations in scheelite with respect to Mo, Sr, As, and Sigma REE + Y. Maps generated from CL imaging and LA-ICP-MS data reveal a strong negative correlation between the intensity of the CL response in scheelite and Mo content. While enrichments of Sr, As, and Sigma REE + Y are noted, none exhibit a correlatable effect with CL response. Furthermore, the qualitative Mo and W X-ray maps produced via SEM-EDS correlate with the corresponding LA-ICP-MS maps of the scheelite grain, successively delineating the zonation patterns observed under CL. This work also demonstrates that the combination of CL and LA-ICP-MS mapping is a powerful tool in the discussion of observed CL textures, elemental relationships, mineral growth history, and paragenesis.

Notes:

GeoRef, Copyright 2018, American Geological Institute.<br/>2017-080351<br/>Britannia Mine<br/>Kumbel Deposit<br/>Sigma Deposit<br/>Zinnwald-Cinovec Deposit