Editing Volcanism (section)

===Melting methods===
====Decompression melting====
[[Decompression melting]] happens when solid material from deep beneath the body rises upwards. Pressure decreases as the material rises upwards, and so does the melting point. So, a rock that is solid at a given pressure and temperature can become liquid if the pressure, and thus melting point, decreases even if the temperature stays constant.<ref>{{Cite book |chapter=3.2 Magma and Magma Formation | date=September 2015 |title=Physical Geology|url=https://opentextbc.ca/geology/chapter/3-2-magma-and-magma-formation/#:~:text=Decompression%20melting%20takes%20place%20within,of%20a%20mantle%20convection%20cell |last1=Earle |first1=Steven |publisher=BCcampus Open Education |access-date=17 March 2024}}</ref><ref name=":2" /> However, in the case of water, increasing pressure decreases melting point until a pressure of 0.208 [[Pascal (unit)|GPa]] is reached, after which the melting point increases with pressure.<ref name=":2" />

====Flux melting====
[[Flux melting]] occurs when the melting point is lowered by the addition of volatiles, for example, water or carbon dioxide.<ref name=":2" /><ref name="NatGeo">{{cite web | url=https://education.nationalgeographic.org/resource/magma-role-rock-cycle/ | title=Magma's Role in the Rock Cycle | publisher=[[National Geographic Society]] | date=19 October 2023 | access-date=17 April 2024 | editor1-first=Jeannie |editor1-last=Evers |editor2-last=Emdash Editing}}</ref> Like decompression melting, it is not caused by an increase in temperature, but rather by a decrease in melting point.<ref>{{Cite web |title=3.2 Magma and Magma Formation | date=September 2015 |url=https://opentextbc.ca/geology/chapter/3-2-magma-and-magma-formation/#:~:text=Decompression%20melting%20takes%20place%20within,of%20a%20mantle%20convection%20cell. | last1=Earle | first1=Steven }}</ref>

====Formation of cryomagma reservoirs====
[[Cryovolcanism]], instead of originating in a uniform subsurface ocean, may instead take place from discrete liquid reservoirs. The first way these can form is a plume of warm ice welling up and then sinking back down, forming a convection current. A [[Scientific modelling|model]] developed to investigate the effects of this on [[Europa (moon)|Europa]] found that energy from tidal heating became focused in these plumes, allowing melting to occur in these shallow depths as the plume spreads laterally (horizontally). The next is a switch from vertical to horizontal propagation of a fluid filled crack. Another mechanism is heating of ice from release of stress through lateral motion of fractures in the ice shell penetrating it from the surface, and even heating from large impacts can create such reservoirs.<ref name=":3">{{Cite book |chapter=Cryovolcanism |title=Planetary Volcanism Across the Solar System |chapter-url=https://ntrs.nasa.gov/api/citations/20210026013/downloads/Quick_%20Chapter5_Cryovolcanism_13Jun2021.docx.pdf |first1=Sarah A. |last1=Fagents |first2=Rosaly M.C. |last2=Lopes |first3=Lynnae C. |last3=Quick |first4=Tracy K.P. |last4=Gregg |editor1-first=Tracy K.P. |editor1-last=Gregg |editor2-first=Rosaly M.C. |editor2-last=Lopes |editor2-link=Rosaly Lopes |editor3-first=Sarah A. |editor3-last=Fagents |date=2021 |publisher=Elsevier |isbn=978-0-12-813987-5 |pages=161–234}}</ref>