resurgent boiling

Resurgent boiling, in a geological context, refers to the exsolution of volatile substances, primarily water, from magma during the late stages of crystallization. This process occurs when the concentration of volatiles in the magma reaches its solubility limit under the prevailing temperature and pressure conditions.1

While the term "resurgent boiling" can be misleading as the exsolved fluid isn't always expelled, it describes a phenomenon related to volcanic activity. Hot springs and geysers, for instance, are manifestations of volcanic activity resulting from groundwater interacting with magma or hot igneous rocks. Geysers specifically erupt due to water reaching its boiling point in deep conduits, with steam bubbles forming and expanding, forcing hot water and steam to the surface.2