High-temperature brine in chalcopyrite-rich quartz vein 40 km southwest of Sudbury, Ontario

2011 ◽  
Vol 48 (10) ◽  
pp. 1369-1385 ◽  
Author(s):  
Eva S. Schandl ◽  
Michael P. Gorton ◽  
Colin J. Bray
Keyword(s):  
High Temperature ◽  
Fluid Inclusion ◽  
Fluid Inclusions ◽  
Minimum Temperature ◽  
Tectonic Evolution ◽  
Quartz Vein ◽  
Regional Metamorphism ◽  
Dissolved Metals ◽  
Igneous Complex ◽  
Sudbury Igneous Complex

The Lac Panache (Nipissing) gabbro intrudes Huronian metasediments ca. 40 km southwest of the Sudbury Igneous Complex. The gabbro contains disseminated sulfides and is in contact with a chalcopyrite-rich quartz vein that crystallized from highly saline fluids (46.8 ± 3 equivalent wt.% NaCl) at a minimum temperature of 420 ± 27 °C. Chloride and carbonate inclusions in opened fluid inclusion cavities in the vein suggest that the brine contained dissolved metals (in addition to NaCl), such as Fe, Cu, Mn, and Co. The weakly altered quartz vein postdated regional metamorphism and was probably contemporaneous with the 1.7 Ga felsic magmatism and attendant albite alteration in the area. Cl-rich scapolite in the gabbro and highly saline fluid inclusions in the quartz vein suggest the existence of circulating hot brine throughout the tectonic evolution of the region. The 2.2 Ga old gabbro contains an abundance of Cl-rich scapolite intergrown with pyrrhotite and chalcopyrite that formed during the early hydrothermal (deuteric) alteration of the gabbro.

scholarly journals Formation of Diagenetic Minerals in the Carboniferous Rock Complex from the Fore-Sudetic Monocline (SW Poland): Fluid Inclusion, Isotopic and Raman Constraints

Minerals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 976
Author(s):  
Aleksandra Kozłowska ◽  
Katarzyna Jarmołowicz-Szulc ◽  
Marta Kuberska ◽  
Krystyna Wołkowicz
Keyword(s):  
Fluid Inclusion ◽  
Fluid Inclusions ◽  
Regional Metamorphism ◽  
Microscopic Analysis ◽  
Thin Sections ◽  
Mineralogical Characteristics ◽  
Low Degree ◽  
Isotopic Analyses ◽  
Homogenization Temperatures ◽  
Clastic Sedimentary

The paper presents the latest state of knowledge on clastic sedimentary rocks from the Carboniferous complex in the SW part of the Polish Lowlands, studied to help determine their potential prospectivity for the occurrence of oil and/or gas deposits. Rocks were analyzed with respect to the petrographic-mineralogical characteristics of the Carboniferous deposits, their diagenesis, determinations of pressure-temperature conditions of mineral formation and the hydrocarbon occurrence. Analyses were carried out on samples from four selected boreholes in the Fore-Sudetic Monocline. After microscopic analysis of rocks and minerals in thin sections, the following techniques were used: luminescence analysis (UV, blue light), microthermometric analysis of fluid inclusions in double-sided polished wafers, XRD analyses, stable isotopic analyses (carbon, oxygen) on calcite and dolomite-ankerite and Raman spectra of fluid inclusions. Orthochemical components, such as carbonates and authigenic quartz, that form cements or fill the veins cutting the sample material have been studied. Fluid inclusion data in quartz and carbonates result in homogenization temperatures of 74–233 °C. The Raman analysis gives temperature estimations for the organic matter of about 164 °C and 197 °C, depending on the borehole, which points to a low coalification degree. The post-sedimentary processes of compaction, cementation and diagenetic dissolution under eo- and meso-diagenetic conditions to temperatures of over 160 °C influenced the present character of the deposits. P-T conditions of brines and methane trapping have been estimated to be ~850–920 bars and 185–210 °C (vein calcite) and ~1140 bars and 220 °C (Fe-dolomite/ankerite). However, locally, temperatures might have been higher (>200 °C), which may be a symptom of local regional metamorphism of a very low degree.

Multiple fluid generations in the Sudbury igneous complex: fluid inclusion, Ar, O, H, Rb and Sr evidence

1999 ◽  
Vol 154 (1-4) ◽  
pp. 1-19 ◽  
Author(s):  
Dan Marshall ◽  
David Watkinson ◽  
Catharine Farrow ◽  
Ferenc Molnár ◽  
Anne-Marie Fouillac
Keyword(s):  
Fluid Inclusion ◽  
Igneous Complex ◽  
Sudbury Igneous Complex ◽  
Complex Fluid

Variation in plagioclase clouding intensity in Matachewan dykes: evidence for the exhumation history of the northern margin of the Sudbury Igneous Complex

2002 ◽  
Vol 39 (6) ◽  
pp. 933-942 ◽  
Author(s):  
J P Siddorn ◽  
H C Halls
Keyword(s):  
Impact Crater ◽  
Regional Metamorphism ◽  
Thin Sections ◽  
Igneous Complex ◽  
Northern Margin ◽  
Sudbury Igneous Complex ◽  
Gneiss Complex ◽  
History Of ◽  
Archean Basement ◽  
Exhumation History

Early Proterozoic Matachewan mafic dykes that cut the Archean Cartier granite – Levack Gneiss Complex north of the Sudbury Igneous Complex (SIC), Canada, are generally metamorphosed to lower amphibolite facies but exhibit locally unaltered plagioclase. These plagioclase feldspars display a clouding similar to that found in the same swarm in the vicinity of the Kapuskasing uplift, about 200 km to the northwest, where the clouding intensity is due to magnetite exsolution and displays a positive correlation with the depth of dyke emplacement. In the Sudbury area, the clouding intensity, obtained by image analysis of thin sections, increases away from the SIC, opposite to the direction of increasing regional metamorphism in the Archean basement. This suggests that the Levack Gneiss Complex north of the SIC was exhumed prior to the intrusion of 2.47 Ga Matachewan dykes and therefore predates the formation of the SIC and associated impact event. The southward tilting of the crust inferred from the plagioclase-clouding data appears to have involved uplift along the Benny Deformation Zone, but the exact age of this deformation is unknown. It may be associated with the 1.8–1.9 Penokean Orogen, 1.85 Ga Sudbury impact crater, or 2.2–2.4 Ga Blezardian Orogen.

scholarly journals Fluid-inclusion studies of high-grade metamorphic rocks of the Ashuanipi complex, eastern Superior Province: constraints on the retrograde P–T path and implications for gold metallogeny

1992 ◽  
Vol 29 (10) ◽  
pp. 2309-2327 ◽  
Author(s):  
Robert P. Moritz ◽  
Serge R. Chevé
Keyword(s):  
High Temperature ◽  
Fluid Inclusion ◽  
Fluid Inclusions ◽  
High Salinity ◽  
Aqueous Fluid ◽  
Metamorphic Rocks ◽  
Gold Deposition ◽  
High Grade ◽  
Low Salinity ◽  
T Path

The high-grade metamorphic rocks of the Ashuanipi complex have been the subject of a microthermometric fluid-inclusion study. Four types of fluid inclusions were observed: CO2-rich fluids; low-temperature, high-salinity H2O fluids; CH4 ± N2-rich fluids; and high-temperature, low-salinity H2O fluids. The regionally distributed CO2-rich fluids are the earliest fluids, and their calculated isochores indicate a clockwise post-peak metamorphic P–T–t path for the Ashuanipi complex. The low-temperature, high-salinity aqueous fluid inclusions are also distributed regionally and can be interpreted as late brines, retrograde metamorphic fluids, or the wicked-off aqueous component of H2O–CO2 fluid inclusions. Both CH4 ± N2-rich fluids and the high-temperature, low-salinity aqueous fluid inclusions were found only locally in gold-bearing metamorphosed banded iron formations. Fluid-inclusion microthermometry, arsenopyrite thermometry, and metamorphic petrologic study at Lac Lilois, one of the principal gold showings, suggest that some gold deposition may have occurred during regional post-peak metamorphic exhumation and cooling at P–T conditions near the amphibolite–greenschist transition. However, it is possible that gold deposition began at higher near-peak metamorphic P–T conditions. Another major gold showing, Arsène, is characterized by CH4 ± N2-rich fluid inclusions, tentatively inferred to be either directly related to gold deposition or responsible for secondary gold enrichment. The association of CH4 ± N2-rich fluids with gold occurrences in the Ashuanipi complex is comparable to gold deposits of the Abitibi greenstone belt and of Wales, Finland, and Brazil.

Geochemistry of pink corundum-bearing feldspathic gneiss, Frenchvale quarry, Cape Breton Island, Canada: metamorphism of albitised, Fe-poor clastic rocks

2019 ◽  
Vol 83 (02) ◽  
pp. 249-260
Author(s):  
J. Victor Owen ◽  
Jacob J. Hanley ◽  
Mitchell J. Kerr ◽  
Matthew Stimson ◽  
Brandon Boucher
Keyword(s):  
Fluid Inclusions ◽  
Quartz Vein ◽  
Isotope Composition ◽  
Regional Metamorphism ◽  
Fluid Phase ◽  
Dolomitic Marble ◽  
Cape Breton Island ◽  
Clastic Rocks ◽  
Silica Alumina ◽  
O Isotope

AbstractFrenchvale quarry, once mined for dolomitic marble, contains pink corundum-bearing, quartz-free/-poor, feldspathic gneiss that is unusually sodic (~7% wt.% Na2O) and iron-poor (~0.6 wt.% Fe2O3), but has silica, alumina and immobile trace-element contents resembling those of suspended fluvial particulate matter (e.g. in the Congo River). The protolith of the gneiss, interpreted as a fine-grained clastic sediment deposited offshore, evidently was albitised prior to deformation and regional metamorphism. Variably-altered gneiss samples show a narrow range of δ18OVSMOW values (8.1 to 10.7‰) and no systematic differences in bulk O isotope composition as a function of alteration intensity. With the exception of an extensively fuchsitised zone adjacent to a thick (1.2 m), cross-cutting quartz vein that contains H2O–NaCl+CO2+CH4-bearing fluid inclusions, the O isotope data do not support interaction of the gneiss with an externally-derived fluid phase except at low fluid:rock ratio, even where granodiorite occurs in direct contact with the gneiss. Fluid inclusions in the quartz vein have bulk $X_{{\rm H}_2{\rm O}}$, $X_{{\rm C}{\rm O}_{\rm 2}}$ and $X_{{\rm C}{\rm H}_{\rm 4}}$ values (in mol.%) of 99.60, 0.14 and 0.26, respectively, as determined by gas chromatography. Although the protolith of the gneiss was associated with carbonate platformal rocks (now marble), corundum is confined to the feldspathic rocks. These feldspathic rocks lack calc-silicate minerals; they are not skarns. As such, they are distinct from well-known Himalayan sapphire and ruby deposits cited previously as analogues of the Frenchvale corundum occurrence.

Surficial geochemical and mineralogical signatures of Ni-Cu-PGE deposits in glaciated terrain: examples from the South Range of the Sudbury Igneous Complex, Ontario, Canada

2021 ◽  
pp. 104301
Author(s):  
Sarah Hashmi ◽  
Matthew I. Leybourne ◽  
Daniel Layton-Matthews ◽  
Stewart Hamilton ◽  
M. Beth McClenaghan ◽  
...  
Keyword(s):  
The South ◽  
Igneous Complex ◽  
Sudbury Igneous Complex
Sign in / Sign up

Export Citation Format

Share Document