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Inanimate Debris Generated by Adverse Weather Conditions
Published in Ahmed F. El-Sayed, Foreign Object Debris and Damage in Aviation, 2022
Magma is the molten material (or rocks) below the Earth’s surface. It can be erupted as lava or pyroclasts. The temperature of magma ranges between 700 °C and 1,300 °C. When the magma reaches the surface, it can extrude as lava. Most lava erupted onto the Earth’s surface is basalt. Bombs
Energy and Environment
Published in T.M. Aggarwal, Environmental Control in Thermal Power Plants, 2021
The heat that is used for geothermal energy can be from deep within the Earth, all the way down to Earth’s core – 4,000 miles (6,400 km) down. At the core, temperatures may reach over 9,000 °F (5,000 °C). Heat conducts from the core to surrounding rock. Extremely high temperature and pressure cause some rock to melt, which is commonly known as magma. Magma convects upward since it is lighter than the solid rock. This magma then heats rock and water in the crust, sometimes up to 700 °F (371 °C).
The Sources and Origin of Magmas
Published in O.A. Bogatikov, R.F. Fursenko, G.V. Lazareva, E.A. Miloradovskaya, A. Ya, R.E. Sorkina, Magmatism and Geodynamics Terrestrial Magmatism Throughout the Earth’s History, 2020
E.V. Sharkov, O.A. Bogatikov, V.I. Kovalenko
For the whole of the Earth’s history, three major types of magma genesis, differing in the character of their source material, can be distinguished: mantle, crustal and mantle–crustal. The character, scale and sometimes the mechanism of magma generation for each type could have varied significantly at every stage of the planet’s evolution.
Inception of the modern North Island (New Zealand) volcanic setting: spatio-temporal patterns of volcanism between 3.0 and 0.9 Ma
Published in New Zealand Journal of Geology and Geophysics, 2021
Adrian Pittari, Marlena L. Prentice, Oliver E. McLeod, Elham Yousef Zadeh, Peter J. J. Kamp, Martin Danišík, Kirsty A. Vincent
Magmatic systems that produced ignimbrite-forming eruptions from the MVC have been understood from cognate granitoid lithics (Brown et al. 1998; Krippner et al. 1998), whole rock pumice, glass and mineral chemistry (Briggs et al. 1993; Cooper et al. 2012; Cooper and Wilson 2014) and U-Pb zircon age spectra (Brown and Smith 2004; McCormack et al. 2009; Cooper et al. 2014). Separate magma systems formed and evolved over a period of 200–250 kyrs (Cooper et al. 2012, 2014) prior to each of the major eruptions (NB: the Rocky Hill and Kidnappers eruptions were derived from the same magma system). Metasedimentary crustal rock was assimilated into the forming rhyolite bodies (Brown and Smith 2004; McCormack et al. 2009). Final pre-eruptive magmas were stored at depths of ∼4.0–6.5 km and at temperatures of 770–840°C (Cooper et al. 2012; Cooper and Wilson 2014).
Proterozoic VanDieland in Central Victoria: ages, compositions and source depths for late devonian silicic magmas
Published in Australian Journal of Earth Sciences, 2019
From the modelling, above, it appears that the sources of the granitic and silicic volcanic magmas that were emplaced within the area underlain by the Selwyn Block must lie at depths greater than 17 km (∼ 23 to 33 km). During silicic magma genesis source temperatures rose to between 745 and 900 °C and, in most places, > 850 °C. Thus, the bulk of the Selwyn Block must have reached granulite-facies conditions. The loss of the silicic magma fractions would have served to densify and somewhat mafitise the deep Selwyn Block crust (e.g. Clemens, 1990). Since the likely heat source for the metamorphism and partial melting was under- and intra-plated mantle-derived magmas (e.g. Petford & Gallagher, 2001), the deep Selwyn Block must now be quite mafic in character.
Formation of Cu–Au porphyry deposits: hydraulic quartz veins, magmatic processes and constraints from chlorine
Published in Australian Journal of Earth Sciences, 2023
G. N. Phillips, J. R. Vearncombe, J. D. Clemens, A. Day, A. F. M. Kisters, B. P. Von der Heyden
Magma is molten rock material that originates beneath the Earth’s surface and may be emplaced and cooled to become an igneous rock. We use the term magma to encompass the molten rock, the dissolved volatiles (gases) and the minerals crystallised from the melt or picked up from elsewhere in the crust. Magmas typically include enclaves of incorporated rocks and smaller aggregates of mineral grains. For porphyry deposits, this discussion of magma is confined to partially molten systems dominated by silicate melt components. Not all previous studies have used the term magma consistently and, to avoid uncertainty, we commonly discuss the separate components of magmas, as listed above.