GEOG 120 Lecture Notes - Lecture 12: Plate Tectonics, Mass Wasting, Mesozoic
Document Summary
Module 7: earth crust dynamics and the rock cycle. * see text table 12. 1 on page 283 of text * Eons phanerozoic is the eon we will mostly consider. Understand the basic era sequence: precambrian, paleozoic, mesozoic, cenozoic. Core solid, metal inner core, liquid outer core of nickel iron - 3500 km radius total. Mantle solid, ultramafic rock 2900 km thick. Crust 4- 10 km thick. A specific part of the upper mantle consisting of comparatively less dense, more brittle material. A zone in which the crust itself rests. Divided into continental and oceanic. Oceanic crust is comparatively thinner and comparatively more dense. Composition of the crust (generalized): Oxygen 47%, silicon 28%, aluminum 8. 1%, iron 5%, calcium 3. 6%, sodium 2. 8%, Potassium 2. 6%, magnesium 2. 1%, others 0. 8% Mineral naturally occurring inorganic substance. Rocks composed of minerals. Variety of characteristics, compositions and ages. Classification based on process of formation. *see cycle of rock transformation diagram in text.
