AST-1A Lecture Notes - Lecture 20: Super Continental, Supercontinent, Proterozoic
Document Summary
Goal: to understand the geologic history of the earth. 4. 6 billion years ago formation of the earth. The cloud of dust and gas creating the sun forms a disc. Inside that disc objects clump together making small meteoroids (10-100k). Sometimes they will break each other apart, but mostly they combine to make bigger meteoroids. Eventually the cores of planets are formed. The core materials in the planets depend on where they form (as it is cooler the further out you go). Sometime in this period an object the size of mars crashes into the earth to form the moon. 7. 5 minutes of class- precambrian time, hades eon) Any land formed gets pushed underneath the surface and is remelted. The atmosphere is 10-250 bars and is mostly water vapor (50%), carbon dioxide (24%), and sulfur dioxide (13%). The original atmosphere made of mostly hydrogen and helium is gone.
