Matches in SemOpenAlex for { <https://semopenalex.org/work/W77818531> ?p ?o ?g. }
Showing items 1 to 73 of
73
with 100 items per page.
- W77818531 abstract "On the island of Newfoundland a number of mafic- to ultramafic intrusions are exposed; most commonly in the Dunnage Zone. These intrusive suites occur in a variety of tectonic environments, and have variable relationships with their host rocks. Nickel is extracted from intrusive rocks of similar compositions throughout the world. This thesis evaluates the potential of three intrusive complexes in Newfoundland to host economic Ni-Cu sulphide and/or platinum group element (PGE) mineralization. -- The Red Cross Lake Intrusive Suite (RCLIS), located in central Newfoundland, is a ca. 431 Ma layered, mafic- to ultramafic intrusion. The Steel Mountain Anorthosite (SMA), located east of Stephenville, in the Southern Long Range Mountains, is a ca. 1275 Ma massive-type anorthosite that hosts abundant Fe-Ti oxides and variable mafic zones. The Taylor Brook Gabbro Suite (TBGS), located southeast of western White Bay, is a ca. 430 Ma gabbroic suite. -- The RCLIS is divided into an Upper and Lower Series (US and LS respectively). The LS is comprised of predominantly gabbro and troctolite layers with minor dunite, olivine gabbro and serpentinite. The US had a gabbroic- to leucogabbroic protolith that is variably altered to pyroxene amphibole gabbro. Geochemical data indicate the RCLIS exhibits an intermediate to alkaline and sub-alkaline composition and is tholeiitic. The RCLIS evolved through fractional crystallization; it exhibits a progressive decrease in MgO and an increase in FeO+Ti0₂ from the LS to the US. Sulfides comprise at most only a few weight percent; the maximum values are from country rock samples. Magmatic sulfides in the LS locally exhibit a high Ni tenor. Plagioclase composition averages An 69 in the LS and An 54 in the US, whereas paragneiss xenolith samples average An 47. Olivine composition averages Fo 83 in the LS and Fo 56 for the US; xenoliths average Fo 36. LS olivine is locally Ni-depleted with respect to its Fo content. δ³⁴S ratios exhibit a range of 5.64‰, from -1.79‰ to +3.85‰. The heaviest ratio is from a country rock sample, whereas igneous samples are closer to 0.00‰, suggesting little country rock contamination. -- The portion of the Steel Mountain Anorthosite (SMA) mapped is predominantly underlain by elongate, diffuse lenses of leuconorite, leucogabbro, norite and norite hosted by massive, recrystallized pink- to lilac coloured anorthosite. Massive Fe-Ti oxides occur locally in noritic units. Gabbroic units are relatively more altered, whereas noritic units more commonly preserve primary textures. Fe-Ti oxides exhibit complex exsolution textures. Lithogeochemistry was effective in separating the majority of samples along an evolutionary trend from Mg-rich melanorites to evolved anorthositic samples. Plagioclase becomes increasingly An-enriched as the rocks become more mafic. Clinopyroxene and orthopyroxene are consistently Mg-rich throughout the SMA. Locally, oxides display strong solid substitution and exsolution textures, which generally result from hematite exsolution in ilmenite or ulvospinel exsolution in magnetite. In the Bishops quarries, hercynite is also common in magnetite. At Sheep Brook, pyrite contains up to 4.7 wt.% Ni in concentric bands. Sperrylite and several other unnamed Pt-Te and Pd-Sb phases were identified. δ³⁴S ratios range from +7.33%o to -2.41‰; the sulfides from Sheep Brook are near 1.00 ‰ whereas sulfides in the Bishop quarries massive oxides are negative at -2.41‰. -- The Taylor Brook Gabbro Suite (TBGS) is heterogeneous at all scales. It comprises a concentrically layered pyroxene amphibole gabbro intrusion that is cut by multiple sets of mafic and felsic dikes. In the northern region of the intrusion a separate, more mafic and coarse-grained zone is recognized. Much of the TBGS has been altered to greenschist assemblages with variable degrees of recrystallization. TBGS samples display well-developed geochemical evolution and are locally Fe-Ti enriched. The TBGS exhibits a sub-alkaline composition and lithogeochemistry suggests that it was emplaced in a within-plate tectono-magmatic environment. δ³⁴S ratios range from +2.22 ‰ to +4.81 ‰, suggesting a magmatic isotopic reservoir. -- The RCLIS has the greatest Ni-Cu-PGE exploration potential because of the presence of olivine-rich ultramafic rocks, evidence for some country rock contamination, locally Ni-depleted olivine and high-Ni tenor sulfides cropping out in mafic and ultramafic rocks. The SMA has the potential for future discoveries of PGE mineralization in the Sheep Brook area; grassroots exploration based on structural analyses and geological mapping would be most effective at finding similar mineralization in the area. The TBGS has marginal exploration future, primarily because there are few rock types with characteristics to host orthomagmatic sulfide bodies. It is possible that the TBGS is only weakly eroded and that favourable stratigraphic horizons lie at depth." @default.
- W77818531 created "2016-06-24" @default.
- W77818531 creator A5055998149 @default.
- W77818531 date "2007-01-01" @default.
- W77818531 modified "2023-09-23" @default.
- W77818531 title "A petrographic and geochemical characterization and the evaluation of the exploration potential for nickel sulfides in several mafic-ultramafic intrusive complexes in Newfoundland" @default.
- W77818531 hasPublicationYear "2007" @default.
- W77818531 type Work @default.
- W77818531 sameAs 77818531 @default.
- W77818531 citedByCount "0" @default.
- W77818531 crossrefType "dissertation" @default.
- W77818531 hasAuthorship W77818531A5055998149 @default.
- W77818531 hasConcept C11872896 @default.
- W77818531 hasConcept C127313418 @default.
- W77818531 hasConcept C139347428 @default.
- W77818531 hasConcept C151730666 @default.
- W77818531 hasConcept C161509811 @default.
- W77818531 hasConcept C167284885 @default.
- W77818531 hasConcept C17409809 @default.
- W77818531 hasConcept C195081551 @default.
- W77818531 hasConcept C2779181077 @default.
- W77818531 hasConcept C2779870107 @default.
- W77818531 hasConcept C2780364934 @default.
- W77818531 hasConcept C42787717 @default.
- W77818531 hasConcept C4992710 @default.
- W77818531 hasConcept C57830525 @default.
- W77818531 hasConcept C59235061 @default.
- W77818531 hasConcept C79605941 @default.
- W77818531 hasConcept C84372278 @default.
- W77818531 hasConceptScore W77818531C11872896 @default.
- W77818531 hasConceptScore W77818531C127313418 @default.
- W77818531 hasConceptScore W77818531C139347428 @default.
- W77818531 hasConceptScore W77818531C151730666 @default.
- W77818531 hasConceptScore W77818531C161509811 @default.
- W77818531 hasConceptScore W77818531C167284885 @default.
- W77818531 hasConceptScore W77818531C17409809 @default.
- W77818531 hasConceptScore W77818531C195081551 @default.
- W77818531 hasConceptScore W77818531C2779181077 @default.
- W77818531 hasConceptScore W77818531C2779870107 @default.
- W77818531 hasConceptScore W77818531C2780364934 @default.
- W77818531 hasConceptScore W77818531C42787717 @default.
- W77818531 hasConceptScore W77818531C4992710 @default.
- W77818531 hasConceptScore W77818531C57830525 @default.
- W77818531 hasConceptScore W77818531C59235061 @default.
- W77818531 hasConceptScore W77818531C79605941 @default.
- W77818531 hasConceptScore W77818531C84372278 @default.
- W77818531 hasLocation W778185311 @default.
- W77818531 hasOpenAccess W77818531 @default.
- W77818531 hasPrimaryLocation W778185311 @default.
- W77818531 hasRelatedWork W1976953385 @default.
- W77818531 hasRelatedWork W1984020503 @default.
- W77818531 hasRelatedWork W1990700465 @default.
- W77818531 hasRelatedWork W1998720216 @default.
- W77818531 hasRelatedWork W2004993647 @default.
- W77818531 hasRelatedWork W2019117493 @default.
- W77818531 hasRelatedWork W2048581009 @default.
- W77818531 hasRelatedWork W2137596541 @default.
- W77818531 hasRelatedWork W2187766602 @default.
- W77818531 hasRelatedWork W2261528997 @default.
- W77818531 hasRelatedWork W2388437661 @default.
- W77818531 hasRelatedWork W2509190825 @default.
- W77818531 hasRelatedWork W2521687234 @default.
- W77818531 hasRelatedWork W2530991753 @default.
- W77818531 hasRelatedWork W2576849394 @default.
- W77818531 hasRelatedWork W2802490163 @default.
- W77818531 hasRelatedWork W2988873770 @default.
- W77818531 hasRelatedWork W3003271842 @default.
- W77818531 hasRelatedWork W3036869126 @default.
- W77818531 hasRelatedWork W67183762 @default.
- W77818531 isParatext "false" @default.
- W77818531 isRetracted "false" @default.
- W77818531 magId "77818531" @default.
- W77818531 workType "dissertation" @default.