EESA06H3 Chapter Notes - Chapter 3: Plate Tectonics, Continental Drift, Oceanic Crust
Document Summary
Earth is composed of concentric layers much like an onion. Each layer has different physical and chemical properties. Lithosphere: cool wet surface of a thin outermost layer that we live on, means "rocky sphere" This shell is brittle and broken into large segments called lithospheric plates. Have been on the move for over 3,000 million years. Have caused continuous rearrangements of continents and oceans called plate tectonics. Lithospheric plates: move and are relative to each other by gliding across the asthenosphe. Plate tectonics: process fuelled by heat created by radioactive decay in the earth"s interior. Objections to wegener"s hypothesis of continental drift were based that rocks are hard an brittle. Folded layers of sedimentary rock are visible in many mountain ranges indicating th rocks can deform. Structures are formed very slowly under considerable heat and pressure. At greater depths, rocks deform plastically and begin to melt sphere terior d and g that.
