If an igneous rock descends into the mantle due to plate tectonics, it will be exposed to intense heat and pressure. What type of rock might it become due to these factors?

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If an igneous rock descends into the mantle and is exposed to intense heat and pressure, it may undergo a process called metamorphism, resulting in the formation of a metamorphic rock. The original igneous rock could transform into a variety of metamorphic rocks depending on its mineral composition and the specific conditions of temperature and pressure it experiences. For example, basalt (an igneous rock) might metamorphose into amphibolite, while granite could change into gneiss. The key processes involved include recrystallization, foliation, and the development of new mineral assemblages, reflecting the high-pressure and high-temperature conditions of the mantle.