He gave many examples of substantial and sometimes commercial quantities of petroleum being found in crystalline or metamorphic basements, or in sediments directly overlying those.
Although made of metamorphic rock, the mountain is actually composed of migmatite, metamorphosed at higher temperatures than gneiss but not sufficiently melted to become granite.
Metamorphic viruses often translate their own binary code into a temporary representation, editing the temporary representation of themselves and then translate the edited form back to machine code again.