EARTH121 Lecture Notes - Lecture 7: Granulite, Blueschist, Schist

• School: University of Waterloo
• Department: Earth Sciences
• Course: EARTH121
• Professor: Keith Delaney

Document Summary

Metamorphism involves complex physical & chemical processes that can affect existing rocks through heat, (cid:272)ha(cid:374)ges i(cid:374) pressure, the flo(cid:449) of fluids deep (cid:271)elo(cid:449) earth"s surfa(cid:272)e or (cid:272)o(cid:373)(cid:271)o. (cid:373)eta. o(cid:272)(cid:272)urs u(cid:374)der e(cid:454)tre(cid:373)e (cid:272)o(cid:374)(cid:272)isio(cid:374)s a(cid:374)d usuall(cid:455) deep (cid:271)elo(cid:449) earth"s surfa(cid:272)e; (cid:272)a(cid:374)"t (cid:271)e observed so most info from ancient metamorphic rocks. Metamorphism: meaning to change form; collectively refers to the changes that take place when a rock is subjected to t/p dff from those in which it originally formed. Metamorphism can be very light where it is hard to distinguish from parent rock or all traces of parent rock can be eliminated. Overall chemical composition of a metamorphic rock largely reflects that of its parent rock but texture & specific mineral makeup depends on physical processes involved in the transformation. Heat, pressure & chemically active fluids are main factors for meta. Dff minerals stable at dff time; ex at 200 degrees clay ->mica.