EAS105 Lecture Notes - Lecture 3: Foraminifera, Carbonate Compensation Depth, Trona

• School: University of Alberta
• Department: Earth and Atmospheric Sciences
• Course: EAS105
• Professor: Fred Clark

Document Summary

Chapter 6, p. 136-157 the changing earth 7e. Definition:- weathering is the physical/mechanical and chemical breakdown of rocks exposed at earth"s surface to smaller particles that may differ in composition from the original substance. Why the two types of weathering aid each other (fig. 6. 8): because physical weathering increases the surface area, and thus susceptibility to chemical weathering, and chemical weathering tends to weaken the integrity of the rock, making it more susceptible to physical weathering. 2kalsi3o8 + 2h+ + 9h2o al2si2o5(oh)4 + 4h4sio4 + 2k+ (kaolinite; (dissolved silica) (orthoclase) a clay: hydration: e. g. (bicarbonate ion, hydrolysis: e. g. (carbonic acid) (calcium ion, solution/dissolution: e. g. caco3 + h2co3 ca2+ + 2hco3 (calcite) Examples of chemical weathering include: (*do not need to memorize or reproduce* i-iv) 4fesio3 + o2 2fe2o3 + 4sio2 (pyroxene) . 2h2o (gypsum: oxidation: e. g. 4fesio3 + o2 + 2h2o 4feo(oh) + 4sio2 (pyroxene) (limonite) (dissolved silica) (hematite) (dissolved silica)