Melting of hydrous and carbonate mineral inclusions in garnet host during ultrahigh pressure experiments

Raman imaging of fluid inclusions in garnet from UHPM rocks (Kokchetav massif, Northern Kazakhstan)

“…It is noteworthy that independently from these mechanisms of origin of these fluid inclusions newly formed garnet could appear as result of reaction interaction between the inclusions and host-garnet. Similar features were found as a run product of high pressure experiments (at T = 900-1100 • C and P = 4 GPa) with garnet from different metamorphic complexes [31]. The origin of the textures are associated with partial melting of polyphase inclusions in situ [31].…”

“…Similar features were found as a run product of high pressure experiments (at T = 900-1100 • C and P = 4 GPa) with garnet from different metamorphic complexes [31]. The origin of the textures are associated with partial melting of polyphase inclusions in situ [31]. All their garnets contained abundant inclusions of hydrous minerals (e.g., phengite, chlorite, phlogopite, zoisite) and carbonates.…”

“…• Break-down low temperature and low pressure polyphase inclusions, captured by growing in garnet during prograde stage, at peak metamorphic conditions. Recently these processes were studied experimentally [31]. It was found that these processes cause formation of new garnet, with a distinctly different composition compared with the initial host-garnet.…”

A perspective view on ultrahigh-pressure metamorphism and continental collision in the Dabie-Sulu orogenic belt

“…The possibility of generation of hydrous melt and supercritical fluid phase by dehydration melting of hydrous minerals has received much attention recently [83,138,[142][143][144][145][146][147] . Partial melting of UHP metamorphic rocks containing hydrous minerals will dramatically affect the rheology of deeply subducted crust and can play a crucial role in the initiation of rapid exhumation of UHP slices [6,148,149] .…”

The composition of nanogranitoids in migmatites overlying the Ronda peridotites (Betic Cordillera, S Spain): the anatectic history of a polymetamorphic basement

“…Most of the MI in crystalline rocks, however, appear today crystallized to a granitic assemblage due to slow cooling at depth, with grain size commonly <1 µm; Cesare et al (2009) named them as nanogranites. A previous and fundamental step for the detailed studies on these crystallized MI has been the development and further refinement of appropriate methodologies to rehomogenize them successfully under high P, in order to prevent MI decrepitation and interaction with the host mineral and matrix rock (Bartoli et al 2013b; see also Malaspina et al 2006;Perchuk et al 2008). After application of this experimental methodology and subsequent analysis of several occurrences of nanogranites, Cesare et al (2015) have observed that the studied MI have bulk compositions varying from granitic to granodioritic, trondhjemitic and tonalitic, and hence they have renamed them as nanogranitoids.…”