Factors Affecting weathering
- Created by: ajcb16
- Created on: 29-01-20 08:35
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- Factors Influencing Weathering 3.2
- Climate
- Pielter Diagram
- warm conditions lead to more chemical weathering
- cold conditions below 0 degrees lead to more physical weathering
- Rock Type
- Sandstone
- the cement is attacked to produce granular disintegeration
- Resistance depends on the cement in the rock
- Joints and bedding planes could provide weaknesses for Physical/Chemical attcak
- Shale
- Iron oxides and sulfides are commonly present, usually oxidised+hydrate
- clay materials are weathered products of other rocks
- Laminations allow water penetration
- Rock softness increases susceptibility to physical weathering
- Limestone
- Carbonate materials are weathered by carbonation then removed in solution
- insoluble clay materials are left as a residue
- Joints allow water penetration and deeper weathering
- Slate
- Slate is chemically resistant to many materials
- Iron compounds within slate (pyrine) are prone to oxidation- leaving brown stains and holes
- Cleavage may allow water penetration and allow freeze-thaw cycles to produce scree fragments
- Basalt
- rich in minerals that are less resistant to hydroloysis
- Basalt is often highly weathered- shown by rusty residues of iron oxides
- The resulting soils are dark coloured and high fertile due to a wide range of elements present held in montmorillonite clay
- Dolerite
- joints allow water penetration which encourages chemical decay and leads to freeze thaw cycles
- Granite
- The quartz+muscovite in granite are resistant to chemical decay
- Quartz and muscovite are left as a residue of sand grains+mica flakes
- Feldspar and other materials are broken down by hydroloysis
- Joints allow water penetration and deeper weathering
- has lots of interlocking crystalline structure
- Sandstone
- Rock Structure
- Joints and bedding planes allow water penetration since cracks within inc PW+CW
- Distance apart of the joints+bedding planes affects size+type of fragements
- Rock texture
- Coarse grained rocks erodes faster than the fine grained rocks due to weathered material that is a large grain that will weaken the rest of the rock
- Igneous rocks are more resistant to disintegration compared to sedimentary rocks
- Relief
- low temps/ north areas+high altidues= freeze thaw- more freeze thaw cycles from a lack of sunlight
- low altidues+high temps=CW
- Landslides can occur due to the lack of protection at the bottom of the relief. The thick layers and accumulation of water at the bottom of the slope encourages CW to occur
- bare rock at the top of the slope can be weathered down by a lack of protected soil
- Climate
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