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Showing 1 to 20 of 402 for “"magmatic"”.
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Studies of Magmatic Systems
Two magmatic systems were investigated using different petrological tools: 1) Origin of Ponza trachyte was studied combining data from MI with trends predicted by thermodynamic modeling. MI data were compared with known phase relations in the ternary feldspar and anorthite-diopside-albite systems …
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Rates of tectonic and magmatic processes in the North Cascades continental magmatic arc
Continental magmatic arcs are among the most dynamic. geologic systems, and documentation of the magmatic, thermal, and tectonic evolution of arcs is essential for understanding the processes of magma generation, ascent and crustal growth. The primary goal of this research is to determine rates of …
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Fluid Inclusion Characteristics in Magmatic-Hydrothermal Ore Deposits
Magmatic-hydrothermal ore deposits are formed in association with aqueous fluids that exsolve from hydrous silicate melts during ascent and crystallization. These fluids are invariably trapped as inclusions in vein-filling minerals associated with hydrothermal fluid flow, and their composition may …
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Modelling and analytical studies of magmatic-hydrothermal processes
Hydrothermal processes play a major role in transporting mass and energy in Earth’s crust. These processes rely on hydrothermal fluid, which is dissolving, transporting and precipitating minerals and distribute heat. The composition of the hydrothermal fluid is specific for various geological …
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A magmatic trigger for the Paleocene-Eocene Thermal Maximum?
… excursion were caused by the intrusion of a magmatic sill complex into organic-rich sediments in the North Atlantic. The intrusion of magma into sedimentary rocks will cause heating and metamorphic reactions in a thermal aureole around the intrusion. If these sediments are rich in organic …
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Magmatic and volcanic processing of volatile and chalcophile elements
… on the relative importance of the various magmatic processes involved. An important and undisputed step in the process is the generation of a hydrothermal saline magmatic fluid with a proclivity to carry high quantities of metals. These fluids exsolve at depth from fractionating magmas and …
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A magmatic trigger for the Paleocene-Eocene thermal maximum?
… excursion were caused by the intrusion of a magmatic sill complex into organic-rich sediments in the North Atlantic. The intrusion of magma into sedimentary rocks will cause heating and metamorphic reactions in a thermal aureole around the intrusion. If these sediments are rich in organic …
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Magmatic volatiles at rifts and arcs: Sources and fractionation effects
… focus on volatiles and the origin of carbon-rich magmatic emissions in the East African Rift, which is perhaps the least understood tectonic system on Earth in terms of mantle degassing. East Africa hosts a diverse array of enigmatic magma compositions, best exemplified by Oldoinyo Lengai volcano …
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Magmatic And Tectonic Evolution Of Southern Tibet And The Himalaya
The Himalaya-Tibetan orogen has become the paradigm for continental collision and is central to deciphering continental tectonics. Neogene extension in the orogen is not predicted by plate tectonic theory, and its significance is widely debated.<br></br><br></br>In the Himalaya, north-south …
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Magmatic processes at basaltic volcanoes: insights from the crystal cargo
A plethora of magmatic processing occurs in magma reservoirs, where melts are stored prior to eruption. Magma reservoirs are complex, open systems, and often multiple reservoirs are partially inter-connected from source to surface, giving rise to the term 'volcanic plumbing system'. Parental melts …
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Experimental and geochemical studies of terrestrial and lunar magmatic process
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1995.
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Studies of volatile evolution in magmatic systems using melt inclusions
… evolution associated with active volcanic magmatic systems is of paramount importance because volatiles control and determine the magnitude of an eruption owing to the large change in molar volume that volatile species show depending on their physical state (volatiles dissolved in silicate …
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Mineralogical, chemical and isotopic diversity in plutonic rock suites from the Coastal Maine Magmatic Province:the role of source region heterogeneity, tectonic setting and magmatic processes
… the plutonic rocks of the Coastal Maine Magmatic Province. A tectonic model is developed in which late Ordovician-Silurian bimodal magmatism is interpreted to reflect crustal melting as a result of intraplating of mantle melts at high crustal levels during a period of tension. Large scale …
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Magma emplacement and deformation in rhyolitic dykes : insight into magmatic outgassing
… distribution of intruded particles and degree of magmatic overpressure required for dyke propagation were governed by the country rock permeability and strength, with pre-existing fractures playing a pivotal governing role. During this stage of dyke evolution significant amounts of exsolved gas …
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Terrestrial Impacts of the Central Atlantic Magmatic Province on western Pangea
… due the emplacement of the Central Atlantic Magmatic Province (CAMP). Evidence has shown that this global carbon cycle perturbation may be the culprit for the end-Triassic extinction. The Whitmore Point Member of the Moenave Formation is a lacustrine deposit with a disputed age of either late …
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The 2014-15 Bárðarbunga-Holuhraun magmatic rifting episode: A seismic study
On 16 August 2014 an unusual sequence of earthquakes began near the southeastern rim of the ice-covered Bárðarbunga caldera in central Iceland. Over the course of two weeks a dyke propagated 48 km beneath the glacier northeastwards and into the Holuhraun lava field, where it erupted for six months, …
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Quantifying The Properties Of Magmatic Intrusions In The Central Andes With Geodesy
Volcanism in convergent arcs is the end result of magma ascending to the Earth's surface. However, many of the details of the ascent process are still debated. In particular, how long does magma persist in reservoirs at particular depths? What is the timescale and physical mechanism of ascent …
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Insights into magmatic processes from the crystal orientation mapping of igneous microstructures
The crystallisation of magma to form solid rock involves many complex physical and chemical processes that remain poorly understood. Mapping crystallographic orientations using electron backscatter diffraction (EBSD) has revolutionised the study of deformed rocks, and is now emerging as a useful …
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Seismicity associated with magmatic intrusions: insights from the Reykjanes Peninsula, southwest Iceland
… governing the ongoing eruptions and the magmatic intrusions that precede them. Microseismicity is a powerful lens through which to view these processes, providing the means to track melt movement as it triggers earthquakes in the surrounding crust. This dissertation makes use of an …
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