GEOG 1120 Lecture Notes - Lecture 9: Chert, Mafic, Ripple Marks
Document Summary
Lecture 9: weathering and sed rocks: intro. Hardness: hard rocks will weather slowly, soft minerals will weather quickly due to solubility and oxidation potential (felsic oxides very fast). Silicates can be summarized using bowen"s dsi (olivine weather very quickly, quartz the strongest). Do not move the rocks, they breakdown on their own. When they physically weather, they rare angular shape. The process of rock breakdown cannot be stopped. Chemical breakdown of rocks: dissolution - some minerals are soluble and dissolve in water. => ex: halite dissolves quickly but rocks do dissolve in water slowly. => halite is the most susceptible to dissolution: oxidation - most commonly fe(2+) with o and h2o to form. => the oxides are the most susceptible to oxidation: hydrolysis - results in the production of ions, give it"s dull appearance. Mafic rocks cannot be stopped from rusting. Weathering => doesn"t move; erosion => moving the pieces once they break down, transport of weathered materials.
