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Modern mineral exploration strategies should take into account nontraditional metallogenic models for a given geological environment. Here we document the first detailed study of a massive sulphide showing associated with the High Arctic Large Igneous Province (HALIP) and Sverdrup Basin and infact, only the second example of mineralization described from Axel Heiberg Island, Queen Elizabeth Islands, Canadian Arctic Archipelago. The Between Lake showing (western Axel Heiberg Island) is a small massive sulphide occurrence within scree/talus below a large ridge of gabbro. It was originally described by explorationists as an orthomagmatic sulphide occurrence hosted within a dioritic dyke. New petrographic and mineralogical analyses indicate that the showing consists predominantly of pyrrhotite with lesser pyrite, trace chalcopyrite, and rare sphalerite. No Ni- or Pb-bearing sulphide minerals were detected. Geochemically, the showing contains some Co and Cu, rare Zn, and generally very low Ni contents ( Key words: Sverdrup Basin, Axel Heiberg Island, Cretaceous, metallogeny, massive sulphides, SEM-MLA analyses, evaporite diapirs. Les stratégies d'exploration minérale modernes devraient tenir compte des modèles métallogéniques non traditionnels pour un milieu géologique donné. Nous documentons la première étude détaillée d'un indice de sulfures massifs associé à la grande province ignée de l'Extrême Arctique ([much less than] High Arctic Large Igneous Province [much greater than] (HALIP)) du bassin de Sverdrup, le deuxième exemple de minéralisation décrite de l'île Axel Heiberg des îles de la Reine-Élisabeth de l'archipel Arctique du Canada. L'indice de Between Lake (ouest de l'île Axel Heiberg) est une petite venue de sulfures massifs entourée de talus d'éboulis sous une imposante crête de gabbro. Il a été décrit à l'origine par des géologues d'exploration comme étant une venue de sulfures orthomagmatiques dans undyke dediorite. De nouvelles analyses pétrographiques et minéralogiques indiquent que l'indice est principalement constitué de pyrrhotite avec de moindres quantités de pyrite, des traces de chalcopyrite et, rarement, de la sphalérite. Aucun S à Ni ou Pb n'a été détecté. Sur le plan géochimique, l'indice contient du Co et du Cu, rarement du Zn et du Nienconcentrations généralement faibles ( Mots-clés : bassin de Sverdrup, île Axel Heiberg, Crétacé, métallogénie, sulfures massifs, analyses par MEB jumelée à la libération de minéraux (MLA), diapirs d'évaporite., Introduction Large Igneous Provinces (LIPs) can be linked, directly or indirectly, to several metallogenic systems (e.g., Ernst and Jowitt 2013; Ernst 2014). Classic examples of orthomagmatic Ni - Cu - [...]

Terrestrial ilmenite has been assessed for its suitability in the preparation of a simulant of lunar high-Ti mare regolith, which is needed to test oxygen production on the lunar surface during future missions. Petrographic observations using optical and electron microscopes revealed that ilmenite grains in the Mirepoix, Sanford Lake, and Degrosbois Fe-Ti oxide deposits from Grenvillian anorthosite massifs contain hercynite in their rims but that hematite exsolution is absent in three of eight studied samples. Electron microprobe analyses showed that the ilmenite grains vary in Ti[O.sub.2] from 38.82 to 52.34 wt.%; in FeO from 33.15 to 45.88 wt.%; in [Fe.sub.2][O.sub.3] (calculated from stoichiometry) from 2.18 to 27.03 wt.%; in MgO from 0.05 to 2.49 wt.%; and in MnO from 0.26 to 1.51 wt.% and are thus comparable in composition to lunar ilmenite. Ilmenite, free of hematite, in two samples was homogeneous in composition (e.g., sample SL1: 50.4-51.4 wt.% Ti[O.sub.2]). Two sub-solidus reactions occurred amongst the oxide minerals in the studied deposits: (i) exsolution of hercynite in magnetite; and (ii) reaction between the hematite component in the ilmenite and the ulvospinel component of the magnetite, forming new ilmenite, which includes the hercynite. The reaction between the hematite component in the ilmenite and the ulvospinel component of the magnetite, when conditions are favorable for diffusion, produces ilmenite grains that are homogenous in composition and free of hematite exsolution. Ilmenite with little or no [Fe.sup.3+] may occur in massive, fine-grained, and metamorphosed Fe-Ti oxide deposits and provide a terrestrial analogue source of ilmenite useful for the production of lunar mare simulant. L'emploi de l'ilmenite terrestre pour developper un simulant de regolithe de mare lunaire riche en Ti, ce qui est essentiel pour tester les methodes de production d'oxygene lors de missions future, a ete evalue. L'observation petrographique au microscope optique et au microscope electronique a balayage a revele que les echantillons provenant des gisements de d'oxydes de Fe-Ti de Mirepoix, de Sanford Lake et de Degrosbois, compris dans les massifs anorthositiques du Grenville, contiennent des grains d'ilmenite avec une bordure de spinelle alumineux (hercynite) mais que trois des huit echantillons etudies ne contenaient pas d'exsolutions d'hematite. Les analyses a la microsonde electronique ont permis de determiner que la composition des grains d'ilmenite varie de 38,82 a 52,34 % poids de Ti[O.sub.2]; de 33,15 a 45,88 % poids de FeO; de 2,18 a 27,03 % poids de [Fe.sub.2][O.sub.3] (le [Fe.sub.2][O.sub.3] etant calcule a partir de la stoechiometrie de l'ilmenite); de 0,05 a 2,49 % poids de MgO et de 0,26 a 1,51 % poids de MnO. Ces concentrations se comparent donc aux concentrations des memes elements dans l'ilmenite lunaire. Dans deux echantillons etudies, l'ilmenite ne contenait pas d'exsolution d'hematite et etait de composition homogene (p. ex. echantillon SL1 : 50,4-51,4 % poids de Ti[O.sub.2]). Deux reactions sub-solidus ont eu lieu entre les oxydes dans les echantillons etudies : (i) l'exsolution de l'hercynite dans la magnetite; et (ii) la reaction entre l'hematite, contenue dans un grain d'ilmenite, et l'ulvospinel, contenu dans un grain de magnetite, ce qui a produit de l'ilmenite en continuite optique avec le grain d'ilmenite primaire, incluant l'hercynite. Lorsque les conditions sont favorables a la diffusion, cette reaction produit des grains d'ilmenite ne contenant pas d'exsolution d'hematite et qui sont de composition homogene. L'ilmenite contenant peu ou pas de [Fe.sup.3+] est analogue en composition a l'ilmenite lunaire et pourrait se trouver dans des gisements massifs d'oxyde de Fe-Ti a grains fin et metamorphoses. Cette ilmenite pourra servir a la production de simulant de regolithe de mare riche en Ti., Introduction In the list of recommendations agreed upon by the Canadian Planetary Geology and Geophysics (PG&G) community and submitted to the Canadian Space Agency (CSA), there is clear interest in [...]

This Special volume published by the Canadian Journal of Earth Sciences consists of a collection of six papers on the petrology, geochemistry, and metallogeny of igneous rocks emplaced in large igneous provinces (LIPs). The papers provide a snapshot of results presented at a Special Session of the 2017 Geological Association of Canada--Mineral Association of Canada Joint Annual Meeting held in Kingston, Ontario, by members of the vibrant geoscience community dedicated to the study of LIPs. Participants applauded the idea of a joint session on these topics and as a result, the session fostered animated discussions and new collaborations. The scope of magmatic and metallogenic studies of LIPs often precludes the type of brainstorming that took place during the meeting. This Special volume demonstrates that a robust understanding of magmatic processes represents the essential first step towards the search for mineral deposits in LIPs worldwide. Key words: large igneous provinces, integrated geoscience studies, petrology, geochemistry, metallogeny. Ce volume spécial publié par la Revue canadienne des sciences de la Terre comprend six articles sur la pétrologie, la géochimie et la métallogénie des roches ignées mises en place dans les grandes provinces ignées (GPI). Les articles donnent un aperçu des résultats présentés lors d'une session spéciale de la réunion annuelle conjointe 2017 de l'Association géologique du Canada - Association minéralogique du Canada tenue à Kingston, en Ontario, par des membres de la communauté géoscientifique dynamique qui se consacre à l'étude des GPI. Les participants ont applaudi l'idée d'une séance conjointe sur ces sujets et, par conséquent, la séance a suscité des discussions animées et de nouvelles collaborations. L'échelle des études magmatiques et métallogéniques des GPI exclut souvent le type de remue-méninges qui a eu lieu pendant la réunion. Ce volume spécial démontre qu'une solide compréhension des processus magmatiques représente la première étape essentielle vers la recherche de gisements minéraux dans les grandes provinces ignées du monde entier. Mots-clés : grandes provinces ignées, études géoscientifiques intégrées, pétrologie, géochimie, métallogénie., Introduction Large igneous provinces (LIPs) are characterized by massive outpourings of predominantly mafic magma in the continental and oceanic domains. Over the past century, geoscientists have studied the stratigraphy, volcanology, [...]

The first Special Issue published by the Canadian Journal of Earth Sciences in the field of planetary sciences consists of a collection of nine papers on astromaterials, planetary geology, and Earth-based analogues. We describe the milestones that led to the development of the planetary geology and geophysics (PG&G) community in Canada over the past 5 years, which culminated in record-breaking attendance at a special session of the 2011 GAC-MAC-SEG-SGA Joint Annual Meeting held in Ottawa. The idea of a Special Issue was met with enthusiasm by delegates from coast to coast. By connecting the fields of earth and planetary sciences, the Canadian Journal of Earth Sciences pioneers a new vision for geoscience that expands the options available to Canadians who wish to publish their research at home. Ce premier numero special publie par la Revue canadienne des sciences de la Terre dans le domaine des sciences planetaires comprend neuf articles portant sur astromateriaux, la geologie des planetes et les analogues terrestres. Nous y decrivons les evenements marquants qui ont conduit au developpement de la communaute canadienne de geologie et de geophysique planetaires au cours des cinq dernieres annees; par ailleurs, cet interet a donne lieu a une participation sans precedent lors d'une session speciale du Congres conjoint GAC-MAC-SEG-SGA tenu a Ottawa en 2011. Les delegues d'un ocean a l'autre ont accueilli avec enthousiasme l'idee d'un numero special de la Revue. En reunissant les domaines des sciences de la Terre et des Planetes, la Revue canadienne des sciences de la Terre ouvre une nouvelle vision pour les geosciences qui elargira les options disponibles aux Canadiens qui voudraient publier leur recherche dans leur pays. [Traduit par la Redaction], Thus, among the most fundamental areas of analysis are the nature of planetary surfaces, the processes and sequence of events implied by their geologic records, and the structure and state [...]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Terrestrial ilmenite has been assessed for its suitability in the preparation of a simulant of lunar high-Ti mare regolith, which is needed to test oxygen production on the lunar surface during future missions. Petrographic observations using optical and electron microscopes revealed that ilmenite grains in the Mirepoix, Sanford Lake, and Degrosbois Fe-Ti oxide deposits from Grenvillian anorthosite massifs contain hercynite in their rims but that hematite exsolution is absent in three of eight studied samples. Electron microprobe analyses showed that the ilmenite grains vary in TiO2 from 38.82 to 52.34 wt.%; in FeO from 33.15 to 45.88 wt.%; in Fe2O3 (calculated from stoichiometry) from 2.18 to 27.03 wt.%; in MgO from 0.05 to 2.49 wt.%; and in MnO from 0.26 to 1.51 wt.% and are thus comparable in composition to lunar ilmenite. Ilmenite, free of hematite, in two samples was homogeneous in composition (e.g., sample SL1: 50.4-51.4 wt.% TiO2). Two sub-solidus reactions occurred amongst the oxide minerals in the studied deposits: ( i) exsolution of hercynite in magnetite; and ( ii) reaction between the hematite component in the ilmenite and the ulvöspinel component of the magnetite, forming new ilmenite, which includes the hercynite. The reaction between the hematite component in the ilmenite and the ulvöspinel component of the magnetite, when conditions are favorable for diffusion, produces ilmenite grains that are homogenous in composition and free of hematite exsolution. Ilmenite with little or no Fe3+ may occur in massive, fine-grained, and metamorphosed Fe-Ti oxide deposits and provide a terrestrial analogue source of ilmenite useful for the production of lunar mare simulant. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The first Special Issue published by the Canadian Journal of Earth Sciences in the field of planetary sciences consists of a collection of nine papers on astromaterials, planetary geology, and Earth-based analogues. We describe the milestones that led to the development of the planetary geology and geophysics (PG&G) community in Canada over the past 5 years, which culminated in record-breaking attendance at a special session of the 2011 GAC-MAC-SEG-SGA Joint Annual Meeting held in Ottawa. The idea of a Special Issue was met with enthusiasm by delegates from coast to coast. By connecting the fields of earth and planetary sciences, the Canadian Journal of Earth Sciences pioneers a new vision for geoscience that expands the options available to Canadians who wish to publish their research at home. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Geochemical data, from the Mars Meteorite Compendium web site, for 13 basaltic meteorites, possibly from only four localities on Mars, are used to study Martian petrogenetic processes. To achieve this goal, an exploratory data analysis technique, multidimensional scaling (MDS), is used to quantitatively assess the relative behavior (measured with correlation coefficients) of 160 incompatible element ratios involving 25 'trace' elements. The ratios behave as in Earth basalts, suggesting that relative element incompatibility is similar in both planets. Because mineralogy controls incompatibility, the mineralogy of Earth and Mars mantles appears similar. In addition, results suggest that ratios involving elements with highly different incompatibility (e.g., La/Yb) are dominantly controlled by % melting. Plots of SiO2 (pressure proxy; decreases with increasing pressure) versus La/Yb and Nb/Y (decrease as melting increases) imply that Mars basalts, like Earth tholeiites, reflect high percentages of melting, but opposite to Earth, % melting appears to increase with increasing pressure. The moderately correlated, positive, SiO2-La/Yb Mars relationship parallels highly correlated Lunar KREEP data and contrasts with Earth's negative correlation. The positive relationships may reflect restricted mantle convection in some (Mars and the Moon are smaller) planetary bodies. Using similarly incompatible element ratios that are sensitive to source composition, to compare Mars and Earth with MDS, Mars sources most resemble depleted Earth mantle. Additionally, these ratios group Mars sources into enriched, depleted, and intermediate types. The groupings are the same as those suggested by isotopes, and we conclude that trace element data support the hypothesis that chemical variation in Mars may reflect crystallization of a Mars magma ocean. The natural patterns in ratios and samples revealed using MDS, which has no a priori information about relationships, support integrity of the geochemical data set, despite potential shortcomings such as small sample sizes, alteration, and weathering. However, whether the meteorites are representative of Mars as a whole is unknown. [ABSTRACT FROM AUTHOR]

The Paint Pots are a natural Fe-SO4 acid spring system along the Kicking Horse Rim, a major geological feature that has controlled fluid flow and mineralization over geologic time. The very low pH (∼3) and extremely high trace metal concentrations of the springs are anomalous and greatly exceed health limits (Zn = 35.8 mg/L, Pb = 0.461 mg/L, As = 82.7 ppb). Sulphur isotopes (δ34S and δ18O in sulphate equal to +11.4 and -12.1 ‰, respectively) are consistent with sulphide oxidation. Mass balance calculations indicate that the springs must have derived their acidity and metal content from natural weathering of a pyrite-rich ore deposit in the vicinity. Several ore deposit types occur along the Kicking Horse Rim, with the Mississippi Valley Type (MVT) style being the most consistent with the source of the spring waters. At the spring outlet, Fe-rich waters oxidize, forming large cone features of Fe-O precipitates, predominantly goethite. A diverse microbial community has been identified in the site that is distinct from those found at acid mine drainage sites. At one site, there was a high proportion of the bacterial candidate division WPS-2, the first time that this group has been detected as the predominant phylum in a community. Compared with anthropogenically influenced acid mine drainage sites that have been studied to date as Mars analogues, the unique uncultured organisms found in the Paint Pots provide a distinct analogue site that can offer insights into the diversity of extremophilic organisms in more natural environments. [ABSTRACT FROM AUTHOR]