EESA06H3 Lecture Notes - Lecture 10: Shatter Cone, Cambrian Explosion, Craton
Document Summary
Superconinent cycle (500 million years long: paradigm"/"tool kit" to examine earth history, can be deconstructed. Obducion: crustal thickening how mountains grow. Craton and cratonizaion: how coninents grow, craton is synonymous w/ shield". Province (old crust now embedded in coninents: or terrane (large crustal block that came from somewhere else) Shater cone (fracture let by meteorite impact: structure found in rock. Fiord: deep valley cut by glaciers now looded by the sea. 540 million years ago cambrian explosion and ediacaran fauna. Gneiss (highly metamorphosed rocks) mylonite: banded/foliated, most common rock of canadian shield. Pleistocene: time for ice ages, last 2 million years, needed climate change to push evoluion. Anthropocene (age of man): modern industrial era: 1750 ad beginning on industrial revoluion. Most of canadian shield extends into us but are covered by younger rocks. When oceans open and close they never go back to exact same size and posiion b/c there"s.
