Barite in the approximately 513 Ma Lemarchant volcanogenic massive sulphide (VMS) deposit, Newfoundland, consists of granular and bladed barite intimately associated with mineralization. Regardless of type, the composition of barite is homogeneous at bulk rock and mineral scale containing predominantly Ba, S, and Sr, with minor Ca and Na. The barite has homogeneous sulphur isotope compositions (δ34Smean = 27‰), similar to Cambrian seawater sulphate (25–35‰) and Sr isotope compositions (87Sr/86Sr = 0.706905 to 0.707485). These results are consistent with barite having formed from fluid–fluid mixing between Cambrian seawater and VMS-related hydrothermal fluids. The 87Sr/86Sr values in the barite are lower than mid-Cambrian seawater, which suggests that some of the Sr was derived from the underlying Neoproterozoic basement. Fluid inclusions in bladed barite are low-salinity, CO2-rich inclusions with homogenization temperatures between 245°–250 °C, and average salinity of 1.2 wt.% NaCl equivalent. Estimated minimum trapping pressures of between 1.7 to 2.0 kbars were calculated from aqueous–carbonic fluid inclusion assemblages. The fluid inclusion results reflect regional metamorphic reequilibration during younger Silurian regional metamorphism, rather than primary fluid signatures, despite the preservation of primary barite and fluid inclusion textures. These results illustrate that barite in VMS deposits records the physicochemical processes associated with VMS formation and the sources of fluids in ancient VMS deposits, as well as seawater sulphate and basement isotopic compositions. The results herein are not only relevant for the Lemarchant deposit but also for other barite-rich VMS deposits globally.
Skip Nav Destination
Article navigation
Research Article|
December 04, 2019
Geology, mineralogy, S and Sr isotope geochemistry, and fluid inclusion analysis of barite associated with the Lemarchant Zn–Pb–Cu–Ag–Au-rich volcanogenic massive sulphide deposit, Newfoundland, Canada
Marie-Ève Lajoie;
a
Department of Earth Sciences, Memorial University of Newfoundland, St. John’s, NL A1B 3X5, Canada.Corresponding author: Marie-Ève Lajoie (email: mlajoie@osiskomining.com).
Search for other works by this author on:
Stephen J. Piercey;
Stephen J. Piercey
a
Department of Earth Sciences, Memorial University of Newfoundland, St. John’s, NL A1B 3X5, Canada.
Search for other works by this author on:
James Conliffe;
James Conliffe
b
Geological Survey of Newfoundland and Labrador, Department of Natural Resources, 50 Elizabeth Avenue, St. John’s, NL A1B 4J6, Canada.
Search for other works by this author on:
Daniel Layton-Matthews
Daniel Layton-Matthews
c
Department of Geological Sciences and Geological Engineering, Queen’s University, Kingston, ON K7L 3N6, Canada.
Search for other works by this author on:
Canadian Journal of Earth Sciences (2020) 57 (1): 133–166.
Article history
received:
23 Jun 2018
accepted:
12 Feb 2019
first online:
21 Jan 2020
Citation
Marie-Ève Lajoie, Stephen J. Piercey, James Conliffe, Daniel Layton-Matthews; Geology, mineralogy, S and Sr isotope geochemistry, and fluid inclusion analysis of barite associated with the Lemarchant Zn–Pb–Cu–Ag–Au-rich volcanogenic massive sulphide deposit, Newfoundland, Canada. Canadian Journal of Earth Sciences 2019;; 57 (1): 133–166. doi: https://doi.org/10.1139/cjes-2018-0161
Download citation file:
You could not be signed in. Please check your email address / username and password and try again.
Email alerts
Index Terms/Descriptors
- alkaline earth metals
- barite
- Cambrian
- Canada
- carbon dioxide
- chemical composition
- Dunnage Zone
- Eastern Canada
- electron probe data
- fluid inclusions
- gold ores
- ICP mass spectra
- inclusions
- isotope ratios
- isotopes
- lithostratigraphy
- mass spectra
- massive deposits
- massive sulfide deposits
- metal ores
- metals
- mineralization
- Newfoundland
- Newfoundland and Labrador
- Paleozoic
- petrography
- S-34/S-32
- silver ores
- spectra
- Sr-87/Sr-86
- stable isotopes
- strontium
- sulfates
- sulfur
- textures
- zinc ores
- Lemarchant Deposit
- Bindons Pond Formation
Latitude & Longitude
Citing articles via
Related Articles
Mineralogy and Metal Zoning of the Cambrian Zn-pb-cu-ag-au Lemarchant Volcanogenic Massive Sulfide (vms) Deposit, Newfoundland
The Canadian Mineralogist
Related Book Content
Late Mesozoic to Quaternary intraplate magmatism and its relation to the Neoproterozoic lithosphere in NE Africa—New data from lower-crustal and mantle xenoliths from the Bayuda volcanic field, Sudan
Volcanism and Evolution of the African Lithosphere
A reevaluation of the tectonic history of the Dashwoods terrane using in situ and isotope-dilution U-Pb geochronology, western Newfoundland
New Developments in the Appalachian-Caledonian-Variscan Orogen
Ore Genesis Constraints on the Agdarreh and Zarshouran Carlin-Style Gold Deposits in the Takab Region of Northwestern Iran
Diversity in Carlin-Style Gold Deposits
Nd-Sr-Pb isotopic signatures of Neoproterozoic–Early Paleozoic siliciclastic rocks in response to changing geotectonic regimes: A case study from the Barrandian area (Bohemian Massif, Czech Republic)
The Evolution of the Rheic Ocean: From Avalonian-Cadomian Active Margin to Alleghenian-Variscan Collision