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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 [...]

It is now widely accepted that flood basalt provinces are important targets in the search for Ni--Cu sulphide ores. These ores may also contain concentrations of the platinum-group elements (PGE) [...]

The Cretaceous geological evolution of the Canadian Arctic was marked by voluminous magmatism comprising Canada's portion of the High Arctic large igneous province (HALIP) that is thought to have resulted from a mantle plume head. This magmatism is largely recorded as extensive Early Cretaceous lavas of the Isachsen Formation, Late Cretaceous continental flood basalts of the Strand Fiord Formation, and an extensive network of dykes and sills forming their plumbing systems. Axel Heiberg Island near South Fiord contains a small, structurally complex portion of the overall network of HALIP tabular intrusions, from which samples from the South Fiord intrusions and Isachsen Formation basaltic lavas were analysed to better understand their petrogenesis. Specifically, we apply trace-element ratios together with Sm-Nd isotope systematics in order to identify processes that shaped the chemical evolution of the South Fiord intrusions and Isachsen Formation lavas, to identify (1) mantle source chemistries and (2) the role of crustal assimilation. On the basis of Sm-Nd isotopic results, South Fiord intrusion magmas were derived from a homogeneous mantle source whereas a more heterogeneous source is invoked for the Isachsen Formation lavas. Furthermore, modelling with Th/ La, Nb/U, Ba/Th and Ba/Nb suggests that South Fiord intrusive magmatism was contaminated by sedimentary rocks from the Sverdrup Basin. Conversely, a trend towards high Ba/Th in Isachsen Formation lavas suggests a subducted sediment component derived from extinct subduction zones. We surmise that (1) South Fiord intrusive rocks are geochemically distinct from the Isachsen Formation lavas and (2) the HALIP mantle plume head intersected and incorporated sediments from ancestral subduction zones to the present-day Aleutian and Alaska subduction zones to produce the Isachsen Formation flows, whereas the South Fiord intrusions (and correlated Strand Fiord magmatism) were generated from plume material that interacted with upper crustal sedimentary rocks. [ABSTRACT FROM AUTHOR]

Gossans resulting from the oxidation of sulphide-rich bedrock occur sporadically across Canada, and these features are routinely indicated on geological maps published by the Geological Survey of Canada (GSC). In the Canadian Arctic Islands, some gossans display reactive zones in permafrost characterized by specific textures and mineralogical facies. In poorly-vegetated areas of the High Arctic, gossans can easily be detected on high-resolution satellite imagery. However, the mechanisms leading to their formation are poorly known. For this study, two reactive gossans located in the early Neoproterozoic Minto Inlier of Victoria Island, Northwest Territories, were investigated to determine if the deposits constitute (1) analogues of mine waste in permafrost and (2) vectors to economic resources. Mineralogy was determined in situ using a portable spectroradiometer, with follow-up laboratory measurements. Site 1, Gossan Hill, is a 75-m topographic high capped by a poorly consolidated, rust-coloured layer overlying pyrite-rich sands, and resembles a classic gossan. Site 2, Gossan Sill, underlies a mineralized gabbroic sill consisting of sulphide-rich veins and pods but appears to be inverted morphologically. Visible–Near Infrared–Short Wave Infrared spectral analyses of surficial materials at Gossan Hill indicate gypsum, goethite and jarosite, and X-ray diffraction (XRD) confirms their presence as well as quartz, illite and feldspar. At Sill Gossan, spectral analyses show gypsum and jarosite; XRD indicates variable amounts of goethite, hematite, pyrite, chlorite, calcite and feldspar. The positive relief and presence of concentric alteration zones at Gossan Hill suggest that cryogenic processes, typical of Arctic regions, are active. Water becomes expelled during the freezing cycle forcing material outwards and along with oxidation of the sulphides, forms variably coloured zones in gossanous material. The inverted stratigraphy at Sill Gossan is more problematic. Constant weathering and mass wasting from the overlying sill and pyrite-rich breccia provide fresh pyrite to the gossan on a regular (seasonal) basis. [ABSTRACT FROM AUTHOR]

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The geochemistry of a suite of lava flows, sills, and dikes from Axel Heiberg and Ellesmere islands in Arctic Canada has been examined to determine the Ni-Cu-platinum group element (PGE) sulfide prospectivity, the Canadian portion of the 130 to 80 Ma High Arctic large igneous province (HALIP). This event can be split into mildly alkaline or transitional and tholeiitic suites, each with distinct provenances, S saturation histories, and Ni-Cu-PGE prospectivity. The mildly alkaline magmas of the HALIP were sourced from a deep, variably enriched part of the mantle, and most probably represent lower-degree partial melts than the tholeiitic parts of the HALIP that were formed from magmas generated by shallower, higher-degree partial melting of a region of unenriched mantle. The two types of magma also differ in their Ni-Cu-PGE magmatic sulfide prospectivity in that the geoehemistry of the majority of the mildly alkaline samples is indicative of unfertile or poorly fertile S-saturated magmas which did not sequester significant amounts of chalcophile elements from the mantle during partial melting, and therefore may be unprospective. In comparison, the presence of chalcophite element-undepleted tholeiitic samples suggests that the magmas forming these rocks were S undersaturated and fertile, and sequestered significant amounts of Cu and PGEs from the mantle during partial melting. Furthermore the presence of chalcophile-depleted and crustally contaminated samples within the tholeiitic suite indicates that the magmas that formed these samples assimilated crustal material and became sulfur saturated prior to emplacement, segregating magmatic sulfides that may have been deposited and left behind within ultramafic or mafic intrusive rocks associated with the tholeiitic segments of the Canadian HALIR Interestingly, some tholeiitic flows are crustally contaminated but are only weakly Pd depleted; this suggests that these flows may have locally assimilated crustal material, which led to only minor S saturation and in situ formation of voluminously insignificant magmatic sulfides. These observations suggest that the tholeiitic portion of{he Canadian HALIP is prospective for Ni-Cu-PGE sulfide mineralization, and that mafic-ultralnafic sequences associated with this suite should be targeted for mineral exploration. Identification of parts of the Canadian HALIP where magmas assimilated S-bearing sedimentary material could also be a useful tool for exploration. The data and interpretations presented here provide a number of scientific hypotheses that could be tested for other parts of the circum-Arctic HALIP event. [ABSTRACT FROM AUTHOR]

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.)

Gossans are surficial deposits that form in host bedrock by the alteration of sulphides by acidic and oxidizing fluids. These deposits are typically a few meters to kilometers in size and they constitute important vectors to buried ore deposits. Hundreds of gossans have been mapped by field geologists in sparsely vegetated areas of the Canadian Arctic. However, due to Canada's vast northern landmass, it is highly probable that many existing occurrences have been missed. In contrast, a variety of remote sensing data has been acquired in recent years, allowing for a broader survey of gossans from orbit. These include band ratioing or methods based on principal component analysis. Spectrally, the 809 gossans used in this study show no significant difference from randomly placed points on the Landsat 8 imageries. To overcome this major issue, we propose a deep learning method based on convolutional neural networks and relying on geo big data (Landsat-8, Arctic digital elevation model lithological maps) that can be used for the detection of gossans. Its application in different regions in the Canadian Arctic shows great promise, with precisions reaching 77%. This first order approach could provide a useful precursor tool to identify gossans prior to more detailed surveys using hyperspectral imaging. [ABSTRACT FROM AUTHOR]

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.)

The Alpha–Mendeleev ridge complex is a prominent physiographic and geological feature ofthe Arctic Amerasia Basin. The Alpha and Mendeleev ridges are, respectively, the eastern andwestern components of a continuous seafloor high that is approximately 2000 km long and200–400 km wide. A surge of interest in the tectonic evolution of Arctic submarine featureshas led to a wealth of new geophysical data collected from the Alpha Ridge. Currentinterpretations of its origin vary but there is compelling evidence that the Alpha Ridge mayhave formed as an oceanic plateau during the Late Cretaceous. Geological samples are rarebut most samples recovered indicate a genetic link with the High Arctic Large IgneousProvince (HALIP). In August 2016, Canada’s Extended Continental Margin-United Nations Convention onthe Law of the Sea Program dredged approximately 100 kg of volcanic rocks from the AlphaRidge. The large size and pristine state of the samples enabled the first comprehensive studyof a single eruptive event in the volcanic record of the Alpha Ridge. The dredgesample is a lapilli tuff containing vitric and basaltic clasts. Textural evidence and thecoexistence of juvenile and cognate clasts suggest a phreatomagmatic eruption. Thevitric fragments consist of sideromelane glass with abundant plagioclase microlites.Texturally, these basaltic glass lapilli display a fresh glassy core surrounded byFe- and Ti-rich zones and a palagonite rim. Major and trace element analyses ofglassy cores indicate remarkably uniform, mildly alkaline basaltic compositions. Theplagioclase-bearing glass yielded a 40Ar/39Ar plateau age of 90.40 ± 0.26 Ma (2σ error)which included 89% of 39Ar released. We interpret this result to represent the eruption age ofthe plagioclase microlites and consequently, of the host basaltic glass lapilli inthe tuff. Volatile species analyses by infrared spectroscopy on the fresh basalticglass suggests that the melt was effectively degassed to shallow level. Assumingequilibrium degassing, the homogeneous resulting values of H2Ototal in the range0.1 to 0.19 wt.% (1σ error) indicate subaerial or shallow eruption (surface to 80m). The new 40Ar/39Ar age for the sample is consistent with a 40Ar/39Ar age of 89 ± 1 Maobtained for a sample of tholeiitic basalt dredged from the central part of the Alpha Ridge,and with the range of ages reported for HALIP igneous rocks exposed onshore in theCanadian Arctic Archipelago (130-80 Ma). Our new data provide evidence for localemergence of the Alpha Ridge in the Late Cretaceous. A comparison of the Alpha Ridge andKerguelen Plateau–Broken Ridge Large Igneous Province (LIP) provides new insights on theepisodic nature of LIP magmatism and variations in eruptive style through time. [ABSTRACT FROM AUTHOR]

The Canadian Space Agency (CSA) is involved in several space exploration research projects carried out through the Canadian Analogue Research Network (CARN). All these projects require the visualization, manipulation, analysis, and interpretation of geospatial terrestrial information for comparison with the existing planetary databases. The large amount of data gathered through these projects require easy access and processing ability for principal investigators and their students at Canadian universities, CSA staff, and stakeholders in government, industry, and at space agencies worldwide. We present the results of a project in development to create an Internet-based Geographic Information System (WebGIS) for terrestrial analogue research and planetary databases at the CSA The project has three objectives: (1) to promote and facilitate research at analogue sites in Canada; (2) forge stronger links with the international earth and planetary science community by sharing geospatial information and (3) give visibility to the CSA in the field of analogue and planetary database management. For this project, we are testing an OpenGIS architecture made available on the Internet and built according to the international standards developed by the Open Geospatial Consortium. In addition to reducing costs, this approach allows: (1) flexibility in database management, (2) interoperability with a Web Map Service (WMS), (3) the ability to create multilayered databases and queries for comparative studies, and (4) regular updates to include data from ongoing terrestrial analogue and planetary missions. Similar solutions already exist but are largely dedicated to terrestrial databases except in a few cases for global planetary information. The particular feature of the proposed WebGIS solution will be to focus on a detailed comparison of terrestrial and planetary geospatial databases using a list of specific queries developed in collaboration with experts from the scientific community in Canada and internationally. [ABSTRACT FROM AUTHOR]

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]