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Magma is defined as a hot, viscous liquid rock material that can contain gases and solid particles. It crystallizes to form igneous rocks at temperatures ranging from 600 to 1400 °C and is the source of high-temperature geothermal resources. AI generated definition based on: Geothermal Energy, 2007. About this page.
20 oct. 2024 · The existence of magma reservoirs beneath the WVF remains contentious, thus we calculated the ascent rates of mantle fluids under two scenarios. (1) Assuming no magma reservoir exists or magma is located at the base of the crust, with the crust thickness in the WVF (30 km) as the ascent distance for mantle fluids.
The magma evolution of individual units in the TIS seems to be recorded by the geochemistry of their respective zircon populations (Fig. 8). Though the zircon populations analyzed here represent a small subset of the entire TIS, each sample studied has unique trends in trace element space ( Fig. 4 ), which may be used to understand how upper-crustal magmatic systems evolve.
1 janv. 2015 · Magma composition is interpreted from the composition of igneous rocks exposed at the surface and while they have a wide range of compositions they are ultimately derived by melting in the Earth's mantle or the crust. Those derived from the mantle are dominantly basalts, whereas those from the crust are granites.
During the magmatic evolution, fractional crystallization of the carbon-poor ultramafic magma led to the enrichment of alkalis, carbon, iron, and incompatible elements such as REE and HFSEs in the residual magma (Table S7), resulting in the formation of K-feldspar, calcite, magnetite, allanite, and abundant titanite in the calcite-amphibole ...
1 mai 2013 · The magma flow directions of both the basaltic rocks from the Etendeka igneous province of Namibia and from the Paraná province in Brazil show essentially the same trend, implying that rifting preceded flood volcanism, at least in the portion of the magmatic province within 100 km of the nascent spreading ridge (Glen et al., 1997).
Magma cools during transport leading to orders of magnitude increases in its viscosity and eventual solidification (e.g., Currier and Marsh, 2015). Such large variations in magma viscosity makes it a key parameter governing the emplacement and the dynamics of igneous intrusions. However, changes in viscosity are challenging to simulate in both ...
1 déc. 2019 · Magma from the VEI 3 eruption of 1992 decompressed at a rate of ∼0.0073 MPa/s (∼0.3 m/s), while magma from the VEI 2 1995 eruption record decompression rates of ∼0.0014 MPa/s (∼0.05 m/s). These decompression rates fit within the general trend of mass eruption rate (MER) versus decompression rate based on embayment studies for other volcanoes ( Fig. 14 ).
1 déc. 2020 · Fluids simulating magma were injected at different, aligned inlet points located within the analogue brittle overburden, 10 mm from the basal interface. To track magma transport and mixing processes within the models we used different colored fluids injected at different inlets. A stepper motor connected to a central unit allowed us to maintain ...
Magma Chambers. Bruce D. Marsh, in The Encyclopedia of Volcanoes (Second Edition), 2015 1 Introduction. Magma chambers are the virtual and, sometimes, actual classical homes of the physical and chemical processes bringing about differentiation, which is the process to which planet Earth owes its gross structure and great diversity of its igneous rocks.
