EARTH 10 Lecture Notes - Lecture 7: South Georgia And The South Sandwich Islands, Metamorphic Facies, Metamorphic Rock
Document Summary
Erebus: continuously erupting since permanent observation in 1970s; Sidley: highest volcano in antarctica; 4285 m: caldera: large cauldron-like depression that forms following evacuation of a magma chamber/reservoir; large circular depression created by explosive volcanic eruption. Magma erupts from bottom of earth"s surface & erupts and then rock collapses in circular shape when magma gets sucked back down. Deception island, south sandwich islands: fumeral: gas vents (pipe where gas escapes from earth"s surface) Shield volcano: shield-shaped, usually basaltic in composition, broad, low angle slope, hawaii-mauna loa, less violent, peter island, subglacial volcanism. Metamorphic changes: textual changes- grain shape, size, mineral changes: elements recombine to form diff minerals, deformation: foliation- parallel alignment of micas & other minerals to make metamorphic layering, slaty cleavage: parallel fractures along foliation planes. Site of metamorphism: contact: along magma intrusions, little to no deformation, burial: deep burial in sedimentary basins, no deformation, regional: due to tectonic processes, places like subduction zones; most widespread, covers large areas.
