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The Upper Proterozoic Redstone Copper Belt, Mackenzie Mountains, Nwt, Charles Wilson Jefferson
The Upper Proterozoic Redstone Copper Belt, Mackenzie Mountains, Nwt, Charles Wilson Jefferson
Digitized Theses
The Redstone Copper Belt is a 300 km arcuate zone of late Proterozoic stratabound copper occurrences within the Coates Lake Group (proposed) in the Mackenzie Mountains, N.W.T., Canada. The Coates Lake Group was deposited on the eroded surface of shallow marine carbonates and tholeiitic basalts at the top of the Little Dal Group. Six main areas of deposition and preservation were controlled by growth faults during the early part of the Hayhook extensional tectonism (About 750 Ma).;Three formations within the Coates Lake Group record transgression from alluvial fan to sabkha and shallow platformal marine conditions (Thundercloud Formation, proposed); regression from …
The Geochemistry And Mineralogy Of Recent Sediments Of The Niger Delta, Biodun Elijah Olorunfemi
The Geochemistry And Mineralogy Of Recent Sediments Of The Niger Delta, Biodun Elijah Olorunfemi
Digitized Theses
A study of the mineralogical and chemical composition of recent sediments of the Niger delta, Nigeria was undertaken to provide baseline geochemical data and to relate these data to soil fertility, erosion and engineering problems. The mineralogical composition shows that three areas are distinguished: (1) a large kaolinite-quartz zone; (2) restricted kaolinite-beidellite zone; and (3) a highly restricted metastable smectite zone mainly montmorillonite and nontronite. The mineralogy is interpreted as functions of stability, groundwater flow rates, permeability and sea water incursion. Type 1 occupies the dynamic central part of the delta where permeability exceeds 1 Darcy, with rainfall averaging 6.8 …
An X-Ray Scattering And Raman Spectroscopy Study Of Iron(3+), Gallium(3+) And Germanium(4+) Substituted Aluminosilicate Glasses, Grant Stephen Henderson
An X-Ray Scattering And Raman Spectroscopy Study Of Iron(3+), Gallium(3+) And Germanium(4+) Substituted Aluminosilicate Glasses, Grant Stephen Henderson
Digitized Theses
SiO(,2), KFeSi(,3)O(,8) and NaFeSi(,3)O(,8) glass structures were investigated using X-ray radial distribution function (RDF) and quasi-crystalline modelling. Vitreous SiO(,2) exhibits a mean Si-O bond distance of 1.60 (ANGSTROM) and Si ('O) Si angle of 151(DEGREES), similar to previous studies. Modelling of the structure against various SiO(,2) polymorphs suggest that vitreous SiO(,2) (v-SiO(,2)) can best be described as a tridymite-like network consisting of six-membered rings of SiO(,4) tetrahedra of which 2/3 are tridymite-like and 1/3 cristobalite-like.;The structures of KFeSi(,3)O(,8) and NaFeSi(,3)O(,8) glasses both have apparent T-O distances of 1.70 (ANGSTROM) but differ in T-T distances and T ('O) T angles; which …