Weathering: The gradual breakdown of rocks in situ (in their original place) at/close to the ground surface.
Types of weathering:
Freeze-thaw; water percolates into cracks/pores, freezes and expands (approx.9%). Expansion exerts stress, causing cracks to widen.
Salt weathering; salt water evaporates in tidal zone, leaving salt crystals. Crystals grow and exert stress in rock, causing it to break.
Wet/dry cycles; clay-rich rock expands and contracts, forming cracks.
Carbonation; carbonate rock absorbs CO2, water forms weak carbonic acid, reacts with rock, rock dissolves.
Biological; plants prise apart rocks, birds/animals/marine life burrow into cliffs, water becomes acidic when passing through dead vegetation.
Mass Movement: Downhill movement of rock and soil as a response to gravity
Types of mass movement:
Landslide; rapid movement of detached slabs down a slide plane
Rockfall; individual fragments fall from cliff face; freeze-thaw
Mudflow; saturated soils flow downhill, heavy rain
Rotational slip; landslips in weak rock (clay, sand)
Soil creep; very slow downhill movement, rock particles
Marine Erosion: 4 main processes
Hydraulic action; waves breaking against rock
Corrasion; rocks thrown at cliff by sea water, cliff becomes gouged/chipped
Abrasion; "sandpaper" effect of loose rocks against bare rock, surface polished/smooth
Attrition; rocks bash together, they become smaller & smoother
Marine Transportation: 4 main ways sediment is transported
Traction; rolling large/heavy rocks along bed
Saltation; rocks bounced along bed
Suspension; lighter sediment suspended, murky appearance to water
Solution; completely dissolved sediment