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Showing 1 to 20 of 284 for “"basalt"”.
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Basalt alteration and its consequences
… thesis explores the geochemical consequences of basalt alteration in three distinct Earth environments using reactive transport modelling coupled to geochemical analyses. The weathering of basalt creates unique chemical environments that can drive carbonate mineral precipitation and other …
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Documenting Mantle and Crustal Contributions to Flood Basalt Magmatism via Computational Modeling of the Steens Basalt, Southeast Oregon
Flood basalts are enormous volcanic events with volumes of volcanic cover and intrusive equivalents that are affected by and significantly affect the crust. Steens Basalt represents 31,800 km<sup>3</sup> of flood basalt lavas that erupted in eastern Oregon ~16.8 Ma in less than 300,000 years. …
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Pollination of Basalt Daisy (Erigeron basalticus: asteraceae)
<p>Erigeron basalticus (basalt daisy) is a rare plant occupying a very restricted range of approximately 52 km<sup>2</sup> in only two counties (Kittitas and Yakima) in central Washington State. Growing out of the cracks and crevices of basalt columns, the population of E. basalticus is fragmented …
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Evolution of a Flood Basalt Crustal Magmatic System: In Situ Mineral Data and Computational Modeling of the Steens Basalt
Flood basalts are gigantic basaltic eruptions that modify the mass of the crust via intrusion of mantle-derived magma, and change its composition through interaction between magma and crust. The Steens Basalt, located in southeast Oregon, erupted approximately 16.8 million years ago, and is the …
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Glulam beams strengthened with pre-stressed basalt fibres
… of elasticity. To study the effect of gluing basalt fibres on the tension zone of glulam beams an experiment was conducted in the structural laboratory (Sel) of Reykjavik University. 12 glulam beams 3,2 m long, 65 mm wide and 167 mm high in strength class GL30c were randomly divided into 3 …
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Characterisation of ocean island basalt sources : St. Helena
… of two shield volcanoes. The SHRS vary from picrobasalts to phonofites. The former represent mantle derived melts, whereas the remainder of the suite have undergone differing degrees of crystal fractionation. A stratigraphic framework is developed to illustrate temporal geochemical variations over …
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Investigation of the Addition of Basalt Fibres into Cement
… carried out into the effect of the addition of basalt fibres to cement has on its mechanical strength. As well, developing concrete that is more durable, flexible, stronger, and less permeable than traditional concrete has been explored. It has become important to test and verify improvements …
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Elasticity across the post-stishovite transition in subducted basalt
… slabs transport surface hydrated mid-ocean ridge basalt (MORB) into deep Earth, which is chemically and physically distinct from the surrounding mantle. Physical properties of MORB materials are thus important to understand observed seismic Vₛ anomalies. In this dissertation, physical properties …
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Untersuchung von Verbundwerkstoffen mit Basalt- und PBO-Faser-Verstärkung
… werden zwei ausgewählte Fasermaterialien (Basalt- und PBO-Fasern) und als Matrix zwei Thermoplaste (PP und PA6) sowie ein Epoxidharz ausgewählt. Der Einsatz von Commingling-Hybridfäden zur Entwicklung der thermoplastischen Unidirektionalverbunde erfordert Voruntersuchungen zur …
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Deep Earth volatile cycles as revealed by basalt chemistry
… a regulator on our planet’s long term climate. Basalt geochemistry is our most direct probe of Earth’s convecting mantle, however the tendency of volatile elements to form vapour phases deep within volcanic systems obscures the mantle volatile signals inherited by basalts. This thesis explores …
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Volcanological studies of Neogene flood basalt groups in eastern Iceland
Flood basalt groups in the Neogene lava piles of eastern Iceland are subject to investigation. The groups form the stratigraphic section above the Reyðarfjörður central volcano up to the Thingmuli central volcano, mapped by the British geologist G. P. L. Walker and his students in the 1950s and …
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Basalt Magmatism as a Key to Unlocking Cenozoic Dynamic Topography
… insights can be gained by analysing Cenozoic basalt magmatism, which correlate with convectively driven regional uplift across the globe. This dissertation comprises three regional studies. First, Neogene-Quaternary magmatism of the Western Mediterranean region is analysed within a mantle …
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Basalt petrogenesis beneath slow- and ultraslow-spreading Arctic mid-ocean ridges
… lithologies to produce alkaline ocean-island basalts (OIB), an experimental study was carried out measuring clinopyroxene (Cpx)- melt and garnet (Gt)-melt partition coefficients during silica-poor garnet pyroxenite melting for a suite of trace elements, including U and Th, at 2.5GPa and …
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Geochemistry of dolerites from the Parana flood basalt province, southern Brazil
The Cretaceous Parana-Etendeka flood basalt magmatism of South America and " Africa was accompanied by intense intrusive activity. This study examines the geochemistry and petrogenesis of dykes from two regions of southern Brazil. Dykes from the Ponta Grossa region of Parana. State fed the basalt …
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Basalt petrogenesis beneath slow- and ultraslow-spreading Arctic mid-ocean ridges
… lithologies to produce alkaline ocean-island basalts (OIB), an experimental study was carried out measuring clinopyroxene (Cpx)melt and garnet (Gt)-melt partition coefficients during silica-poor garnet pyroxenite melting for a suite of trace elements, including U and Th, at 2.5GPa and …
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Energy absorption performance of braided basalt reinforced composite tubes under axial loads
… to the recent environmental awareness, natural basalt fibre has been getting more demand and interest from preform manufacturers. Hence, the aim of this research is devoted to the investigation of energy absorption performance of novel and eco-friendly braided basalt composite tubes associated …
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Methods for constructing 3D geological and geophysical models of flood basalt provinces
… thesis, realistic 3D geological models of flood basalt provinces are constructed. These models are based on outcrop observations and remote sensing data from the North Atlantic Igneous Province, collected by a variety of methods including terrestrial laser scanning. Geophysical data are added to …
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Evolution of enriched mantle from derivative basalt, peridotite and diamond inclusion geochemistry
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric and Planetary Sciences, 1984.
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Characterization and distribution of lunar mare basalt types using remote sensing techniques
Thesis. 1977. Ph.D.--Massachusetts Institute of Technology. Dept. of Earth and Planetary Sciences.
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