A thermo-mechanical model of the thermal evolution and incorporation of the metamorphic sole in the Oman ophiolite

Ophiolites are remnants of oceanic crust and mantle, now typically found within continental mountain ranges. Particularly in areas once part of the Tethys Ocean, ophiolites are often accompanied by narrow strips of metamorphic rocks, commonly referred to as metamorphic soles. These rocks exhibit peak metamorphic conditions characteristic of either granulite or amphibolite facies. Geochronological studies of Tethyan ophiolites indicate that the development of these metamorphic soles occurred almost simultaneously with the crystallization of the ophiolite's crustal sequence. Geological evidence also suggests that the metamorphism of the sole rocks took place concurrently with deformation, likely at the same time as the ophiolite's obduction. In our research, we explore the metamorphic effects of shearing in an ophiolite sequence overlying a crustal sequence. Our findings reveal that a strong crustal lithology can produce additional heat through the dissipation of mechanical energy, which can explain the high temperatures found in metamorphic-sole rocks. In addition, heating of the footwall rocks eventually leads to the migration of the active shear zone from the mantle sequence into the upper crustal domain. This migration is responsible for the metamorphic sole incorporation at the base of the ophiolite. Finally, we demonstrate that stopping the shearing process rapidly cools these rocks, corresponding with the findings from thermochronological studies from Oman ophiolite.