6 Weathering Processes Chemical _________ - Minerals chemically combine with water_________ - Mineral breakdown through contact with Oxygen (Rust)_________ - Mineral absorption of water causes swelling and stress_________ - Mineral dissolution by waterExamples: Spheroidal Weathering, Karst Topography, Gnamma PitsPhysical_________ - Water freezing induced expansion_________ - Mineral crystal growth induced expansion_________ - Pressure released expansion through unloading_________ - Rapid heating from lightning and firesExamples - Exfoliation Domes and talus slopesExtra
7 Weathering Processes Chemical Hydrolysis - Minerals chemically combine with waterOxidation - Mineral breakdown through contact with Oxygen (Rust)Hydration - Mineral absorption of water causes swelling and stressSolution - Mineral dissolution by water into their ionic formExamples: Spheroidal Weathering, Karst Topography, Gnamma PitsPhysicalFrost Action - Water freezing induced expansionCrystallization - Mineral crystal growth induced expansionSheeting - Pressure released expansion through unloadingThermal Expansion - Rapid heating from lightning and firesExamples - Exfoliation Domes and talus slopesExtra
8 Chemical Weathering Processes HydrolysisOxidationHydrationSolutionAssociated Weathering LandformsSpheriodal WeatheringKarst TopographyGnama Pits
9 Chemical Weathering Hydrolysis This process removes CO2 from the atmosphere, counteracting global warmingMinerals chemically combine with water, substituting silica for hydrogen and weathering individual mineral grainsFeldspar (K, Al, Si, O) + carbonic acid and water residual clays (Kaolinite) + dissolved minerals + Si
10 Chemical Weathering Oxidation Iron bearing minerals (like biotite) combine with Oxygen to generate oxides and softer clay minerals.Rusted railway car; that has undergone oxidation
11 Chemical Weathering Oxidation The Wave, Southern Utah Wupatki, Northern Arizona
12 Chemical WeatheringHydration - Clay minerals absorb moisture along their cleavage planes, dramatically increasing in volume.
13 Chemical Weathering Solution Minerals can dissolve into ions with water, like dissolving sugar in coffeeWater is the universal solvent, capable of dissolving at least 57 of the natural elements
14 Weathering LandformKarst Topography - generated through solution mostly into limestone bedrock
36 Where do you think the different weathering processes dominate on the planet? In the Amazon (Tropical Rainforest)Serengeti of Africa (Savanna)Death Valley (Arid)Minnesota (Humid Continental)The Sierras (High Alpine)Alabama (Humid subtropical)Make a list for each one!!!
37 Importance of Surface Area What will weather quicker, one huge boulder or a huge boulder broken down into a bunch of smaller boulders? Why?
38 What does Weathering DO? The in situ disintegration of rock supplied by tectonic (and isostatic) rock input!
39 Things to Know: What is weathering Chemical processes round edges, physical processes generate anglesTypes of chemical weathering and associated landformsTypes of physical weathering and associated landformsImportance of SURFACE AREANeed Help: WM