Hello, I am currently researching mantle melting mechanisms that are NOT decompression, heating or fluid inclusion. So far I have found mechanisms called "Compression Melting" and "Redox Melting." My question is: does anyone know any more? Thanks!
Ice melts under compression (as will any solid that can melt when heated) because compression is an application of force and the energy transfer heats the solid.
Ice melts under compression because the solidus has a negative slope. Please Register or Log in to view the hidden image! Only substances that have a solidus with a negative slope will melt with increased pressure, and water is atypical in this regard. Most substances behave in the same manner as carbon dioxide:. Please Register or Log in to view the hidden image! This atypical behaviour of water is (as Fragglerocker pointed out) related to the density of the solid versus the density of the liquid, and represents an application of le chateliers's principle - namely (in this instance) that increasing the pressure on the substance pushes the equilibria in the direction of the densist state (for water, liquid, for most other substances solid). A well written guide aimed at people without a background in Chemistry.