revision for EQ2 point 4.3/4.4 Flashcards
Ballards point
Long shore drift, has a curve, not an open area/its tight area.
Coastal erosion
Costal erosion is the gradual wearing away of material (coast line) by the the action of waves. This material is then moved or deposited elsewhere.
Softer rock
Headlands and bays. … Headlands are formed when the sea attacks a section of coast with alternating bands of hard and soft rock. The bands of soft rock, such as sand and clay, erode more quickly than those of more resistant rock, such as chalk. This leaves a section of land jutting out into the sea called a headland.
Harder rock
Hard rocks are more resistant than soft ones, and will form steep cliff faces. This nearly vertical cliff on the north Cornish coast has been formed from basalt, a very hard igneous rock. Despite being exposed to the full force of the sea and frequent gales, it remains almost vertical.
Direct
Occurring because of something being purposely put in place to protect the area of the coastline
Indirect
Occurring because of something used to protect the another area of the coastline
Weathering
It takes place on the land. Most weathering involves the breakdown of rocks but not their removal.
Rock structure
It means the way rocks are arranged, most rocks are in layers of strata.
Rock strata
It can be arranged in 2 ways along the coastline: concordant = parallel to the coastline.
Discordant = perpendicular (90 degrees) to the coast.
Freeze thaw weathering
The water enters the cracks and at night the temperature drops and the water freezes and it expands by 9 percent increase in volume and the pressure is increasing because the ice is pushing against the rocks and it increases their cracks. During the day the temperature increases and the ice in the rocks melt. In the night time the temperature drops, re freezing of more water thats got into the bigger crack. After many cycles this happens again.
Biological weathering
Plant roots and animals burrow into rock and pressure on the rock and break down the structure if the rock and after continuous cycles large cracks are formed
Chemical weathering
Is when chemicals break down rock as a result of a chemical reaction
Hydraulic action
Hydraulic action: is the power and force of water and waves being forced into cracks in the rock
The pressure increases and expands. Rock chips off and the crack gets bigger.
Abrasion
Abrasion: is when rocks are picked up by air and thrown or rubbed against the cliffs.
This action wears away the rock and it is gradually removed.
Solution
Solution: is when the sea becomes very slightly water acidic. This is caused by vegetation near to the cliffs.
This dissolves rocks such as limestone/chalk
Attrition
Attrition: rocks that are held within the waves smash into each other. Gradually the rocks become smaller and smoother
why discordant coastlines erode at a faster rate than concordant coastlines.
Discordant coastlines erode at a faster rate than concordant coastlines because they have different rock types and they are more commonly found in the headlands and bays in the UK. An example of this is that there are softer rocks in bays and harder rocks in headlands. Landforms names include Durdle Door, Old Harry and Beachy Head.
why coastlines erode at different rates?
Coastlines erode at different rates because the water erodes the softer rock which means that it is decreasing the bay. Lulworth cove is in Dorset and it is a hard rock coast that consists of resistant rock such as igneous granite and resistant sedimentary rocks, for example sandstone. Following on from that Lulworth cove has a discordant and concordant rock structure because the disconcordant rock structure meets at a 90 degree angle, the reason why it is also a concordant rock structure because the strata in the coastline is parallel.
where in the UK has the biggest waves
The UK has the biggest waves in the west coast because the predominant wind in this country comes from the south west. Also the fetch comes from the coast of Florida at a distance of 6000km to the UK via the Atlantic Ocean. When the storms happen in the UK, it happens for a few days because the storms form and blow from the Atlantic with winds of up to 40mph. Waves have more power when there are stormy conditions in winter months because the wind gets stronger to push the waves.
the characteristics of waves breaking in the summer and winter
The characteristics of waves breaking in summer is that it adds sediment to the beach through deposition, it’s a constructive wave and it has low wave height. The characteristics of waves breaking in winter is that it removes sediment from the beach through erosion, it’s a destructive wave and it has high wave height.
Joints
Joints:are small cracks found in rocks. They are usually vertical.
Faults
Faults: are larger Cracks caused by past tectonic movement where rocks have moved
How does development (jobs/houses/building) impact on the coastline?
The development impacts on the coastline by coastal flooding and erosion because due to sea levels rising and not enough protection to those who might suffer.
How does industry affect the coastline?
Coasts that have gas terminals are not really attractive for tourists because tourists want a nice sandy beach. An example of this is in Becton in Norfolk coast.
How is Swanage coastline being affected by human processes (management, industry, tourism, transport etc)?
About of half of swanage bay is built up. Swanage is a residential and employment centre and an important tourist resort, centred on its wide sandy beach. Sea defences, including groynes, and a sea wall has been built to protect the beach and the town which is swanage
How is Swanage coastline affected by physical processes (geology, discordant, headland/bays, erosion/deposition)?
Sea defences, including groynes, and a sea wall has been built to protect the beach and the town which is swanage.
