GEOL 1001 Chapter : Chapter 6
Document Summary
Erosion is the removal of sediments by natural processes by natural processes such as wind and rivers. Mass wasting is the downslope movement of masses of earth materials: are the processes that loosen and transport soil and rock downhill. Controls on weathering: properties of parent rock, various minerals weather at different rates, a rocks structure affects its susceptibility to cracking and fragmentation, weathering. Large temperature changes heat=expands cool=contracts: evidence in deserts possibly need chemical weathering first. Hard water : oxidation, reaction where an element loses an electron (oxygen not required) Important olivine, pyroxene, hornblende: pyroxene dissolves, releasing silica and ferrous iron, ferrous iron is oxidized, forming ferric iron, ferric iron precipitates a solid, iron oxide, hematite and limonite, hydrolysis frees fe from silicate structure, ex. Controls of soil formation: parent material, source of weathered mineral material, undergoes physical and chemical changes, residual soils- from bedrock, transported soil- from unconsolidated sediment.
