Coasts Flashcards
(38 cards)
What is a coast?
An area of landmass where the ocean or sea meets the land.
How much coastline is estimated to be around the earth?
Approximately 440,000 km.
What are the five factors that influence the formation of a coast?
- Wind
- Waves
- Currents
- Geology
- Tides
What are sub aerial processes?
Processes that occur right above the water line but not in the atmosphere.
Define hydraulic action.
The process by which pressure from the sea attacks cracks in cliffs, causing erosion.
What is abrasion in coastal processes?
The wearing down of rock surfaces by coastal sediment carried by water.
What does attrition refer to in coastal erosion?
The process where sediment and rocks collide in water, breaking each other down into smaller pieces.
What is solution in the context of coastal erosion?
The process where water dissolves soluble materials in rocks, weakening their structure.
What is salt crystallization?
The process where saline water enters rock cracks and evaporates, causing pressure build-up and rock breakage.
Define freeze-thaw weathering.
The continuous freezing and thawing of water in rock cracks, causing them to break apart.
What is thermal expansion in weathering?
The process where rocks expand and contract due to temperature changes, weakening their layers.
What does pressure release mean in geological terms?
The exposure of underlying rock layers due to the erosion of overlying layers, leading to breakage.
What is oxidation in chemical weathering?
The reaction of oxygen with minerals in rocks, resulting in rust and weakening the rocks.
Define carbonation in the context of weathering.
The process where rainwater mixes with carbonic acid, forming weak acid rain that erodes rocks.
What is hydration in weathering?
The process where rocks absorb water, causing them to expand and break down.
What does hydrolysis refer to in geological processes?
The reaction of water with minerals in rocks, resulting in a clayey texture.
How do plants contribute to biological weathering?
Plants develop roots that expand and weaken the soil, leading to erosion.
What is rock fall?
The fall of regolith to the bottom of a cliff, occurring more on bare cliffs.
What is traction in sediment transport?
The dragging of large, heavy sediments along the river sea bed.
Define saltation in sediment transport.
The movement of medium-sized sediments in a hopping motion along the river bed.
What is suspension in sediment transport?
The floating of tiny fine sediment along the surface of the river.
How do wave cut platforms form?
Through wave action eroding the bottom part of a cliff, which leads to the formation of a flat platform.
What is isostatic change?
The change in the height of land due to weight of ice or tectonic activity.
What is eustatic change?
The change in the volume of ocean water stored.
