COASTS Flashcards
What is 3 types of weathering
Mechanical weathering
Chemical weathering
Biological weathering
Explain process for salt weathering
1 The seawater gets into cracks in the rock.
2) When the water evaporates, salt crystals form. As the salt crystals form they expand, which puts pressure on the rock.
3) Repeated evaporation of saltwater and the forming of salt crystals widens the cracks and causes the rock to break up.
define mechanical weathering
breakdown of rock without changing its chemical composition
define chemical weathering
breakdown of rock by changing its chemical composition
example of mechanical weathering
salt weathering
example of chemical weathering
carbonation weathering
explain process for carbonation weathering
1/ rainwater has carbon dioxide dissolved in it which makes it a weak carbonic acid
2/v carbonic acid reacts with rock that contains calcium carbonate eg chalk so the rocks are dissolved by the rainwater
define biological weathering
breakdown of rock by living things
2 examples of biological weathering
animals such as rabbits burrow into soil on cliff tops
plants roots break down rocks by growing into cracks on their surfaces and pushing them apart
define mass movement
shifting of rocks and loose material down the slope due to gravity
effect of mass movement on coasts
coasts retreat rapidly
what 2 factors increases the chance of mass movement
material is full of water (acts like a lubricant) and makes material heavier
undercutting of slope by erosion will increase the chance of mass movements
2 types of mass movement
slides: materials shifts in straight line
slumps: material shifts with a rotation
2 types of mass movement
slides: materials shifts in straight line
slumps: material shifts with a rotation
4 process of erosion
hydraulic action
abrasion
attrition
solution
