Geologic continuous casting below continental and deep-sea detachment faults and at the striated extrusion of Sacsayhuaman, Peru

In one common type of industrial continuous casting, partially molten metal is extruded from a vessel through a shaped orifice called a mold in which the metal assumes the cross-sectional form of the mold as it cools and soli difies. Continuous casting can be sustained as long as molten metal is supp lied and thermal conditions are maintained. I propose that a similar proces s produced parallel sets of grooves in three geologic settings, as follows: (1) corrugated metamorphic core complexes where mylonitized mid-crustal ro cks were exhumed by movement along low-angle normal faults known as detachm ent faults; (2) corrugated submarine surfaces where ultramafic and mafic ro cks were exhumed by normal faulting within oceanic spreading centers; and ( 3) striated magma extrusions exemplified by the famous grooved outcrops at the Inca fortress of Sacsayhuaman in Peru. In each case, rocks inferred to have overlain the corrugated surface during corrugation genesis molded and shaped a plastic to partially molten rock mass as it was extruded from a mo derate- to high-temperature reservoir.