Partial melting is the phenomenon that occurs when a rock is subjected to temperatures high enough to cause certain minerals to melt, but not all of them. Partial melting is an important part of the formation of all igneous rocks and some metamorphic rocks (e.g., migmatites), as evidenced by a multitude of geochemical, geophysical and petrological studies.[1]
The parameters that influence partial melting include the composition of the source rock, the pressure and temperature of the environment, and the availability of water or other fluids.[2][1] As for the mechanisms that govern partial melting, the main are decompression melting and flux melting. Decompression melting occurs when rocks are brought from higher to lower pressure zones in the Earth's crust, lowering the melting point of its mineral components, thus generating a partial melt. Flux melting, on the other hand, occurs when water and other volatiles get in contact with hot rock, reducing the melting point of minerals, leading to partial melting.[2] With a few exceptions (e.g., Yellowstone[3]), conduction of heat is considered a mechanism too slow and inefficient to partially melt large bodies of rock.[2]
Partial melting is also linked to the formation of ores. Magmatic and hydrothermal ore deposits, such as chromite, Ni-Cu sulfides, rare-metal pegmatites, kimberlites, volcanic-hosted massive sulfide deposits are some examples of valuable natural resources closely related to the conditions of the origin, migration and emplacement of partial melts.[4]
^ abKilinc, Attila (1989-12-01). "Partial melting of crustal rocks". Engineering Geology. 27 (1): 279–299. Bibcode:1989EngGe..27..279K. doi:10.1016/0013-7952(89)90036-7. ISSN 0013-7952.
^ abcAsimow, Paul D. (2016), "Partial Melting", in White, William M. (ed.), Encyclopedia of Geochemistry: A Comprehensive Reference Source on the Chemistry of the Earth, Encyclopedia of Earth Sciences Series, Cham: Springer International Publishing, pp. 1–6, doi:10.1007/978-3-319-39193-9_218-1, ISBN 978-3-319-39193-9, retrieved 2023-02-13
^Huang, H.-H.; Lin, F.-C.; Schmandt, B.; Farrell, J.; Smith, R. B.; Tsai, V. C. (2015-05-15). "The Yellowstone magmatic system from the mantle plume to the upper crust". Science. 348 (6236): 773–776. Bibcode:2015Sci...348..773H. doi:10.1126/science.aaa5648. ISSN 0036-8075. PMID 25908659. S2CID 3070257.
^Ridley, John (2013). Ore Deposit Geology. Cambridge: Cambridge University Press. doi:10.1017/cbo9781139135528. ISBN 978-1-107-02222-5.
Partialmelting is the phenomenon that occurs when a rock is subjected to temperatures high enough to cause certain minerals to melt, but not all of them...
23% partialmelting before the melt deviated from the eutectic, which has the composition of about 43% anorthite. This effect of partialmelting is reflected...
magma. Partialmelting of crustal material. Magma mixing between felsic rhyolitic and mafic basaltic magmas in a magma reservoir Partialmelting of metasomatized...
of partialmelting. This is required because potassium is an incompatible element and tends to enter a melt first, whereas higher degrees of partial melting...
is an older metamorphic rock that was reconstituted subsequently by partialmelting ("neosome"), while the alternate layer has a pegmatitic, aplitic, granitic...
asthenosphere, which leads to partialmelting of the asthenosphere and volcanism. Both dehydration and partialmelting occur along the 1,000 °C (1,830 °F)...
is derived from partialmelting of metasedimentary rocks may have more alkali feldspar, whereas a granite derived from partialmelting of metaigneous rocks...
The magma can be derived from partial melts of existing rocks in either a planet's mantle or crust. Typically, the melting is caused by one or more of three...
through mesophases, states of partial order between solid and liquid. From a thermodynamics point of view, at the melting point the change in Gibbs free...
with different melting points. It can be done by partialmelting of a solid, for example in zone refining of silicon or metals, or by partial crystallization...
spreading at divergent plate boundaries. On Earth, magma forms by partialmelting of silicate rocks either in the mantle, continental or oceanic crust...
that drives partialmelting beneath arcs. It has been shown that the amount of water present in the down-going slab is related to the melting temperature...
geochemical characteristics of magma originally thought to have formed by partialmelting of altered basalt that is subducted below volcanic arcs. Most magmas...
boundary (LAB) is relatively sharp and likely coincides with the onset of partialmelting or a change in composition or anisotropy. Various definitions of the...
degrees of partialmelting (less than 10%) of highly aluminous rocks of the lower crust such as tonalite, monzonite and metamorphic rocks. Melting of such...
re-working the crust for billions of years. These processes include partialmelting, crystallization, fractionation, metamorphism, weathering, and diagenesis...
affinities). The process of planetary differentiation is mediated by partialmelting with heat from radioactive isotope decay and planetary accretion. Planetary...
high degree of partialmelting of the upper mantle, with 30 to 40 percent of the source rock entering the melt. Such a high degree of melting was possible...
composed of the more silicic phases that have a lower melting point. This leads to partialmelting and further segregation of the lithosphere. In addition...
residual solid rock left after partialmelting, and the mesosome the original rock that has not yet experienced partialmelting. Gneisses are characteristic...
the eastern block. Anatectic granite is a kind of rock formed by the partialmelting of the pre-existing crustal rock, which is relatively younger than...
pressure in the rising mantle rock leads to adiabatic expansion and the partialmelting of the rock, causing volcanism and creating new oceanic crust. Most...
released by metamorphic dewatering into the overlying mantle wedge. The partialmelting triggered by the incorporation of volatiles produces mafic magma which...
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