GEOL 2207 Lecture Notes - Sedimentary Rock, Continental Crust, Extrusive Rock
Document Summary
Nearly 4000 minerals have been identified on earth. 20-30 common minerals make up most of earth"s crust. 8 elements form 98% of continental crust. Silicon (si) and oxygen (o) are the most abundant. Rocks are classified based on how they were formed. Igneous rocks: form from a hot liquid called magma that originates deep in the earth that moves up toward the surface. Intrusive had time to cool, big crystals. Most magma (~90%) formed in the earth does not make it to the surface to erupt at volcanoes. Chemical & physical decomposition of a parent rock. Erosion, or removal from the site by water, wind, etc. Transportation of the sediment by some agent e. g. running water, waves, wind, glaciers, gravity. Deposition in some environment e. g. , ocean, stream channels, beaches, lakes. Sedimentary rock finally formed by compression, dehydration, cementation of sediments.
