Coastal Processes and Landforms Final Version, Geo Coastal Landforms
Terms in this set (46)
Wooden/concrete barriers built at a right angle to the beach. They prevent long-shore drift, and build up beaches.
Vertical/sloping structures built along shoreline to stop erosion. They concentrate wave energy and reflect it back to sea.
Rock Armour (Rip Rap)
Large barriers similar to sea walls. They are permeable and dissipate wave energy. They don't suffer wave scour, and they are long lasting.
Artificial off shore protection that form still water areas. They stop waves from eroding the beach, and act like an artificial lagoon.
Replacement of sand/pebbles on eroding beaches.
Sand dunes and cliffs act as natural sea defense. Boardwalks, fences and plantation aid with beach reshaping also.
Pros of soft management
Less expensive, long term/sustainable, less environmental impact
This is a long, curved landform that is built up at the mouth of a river, which is where the river widens and ends. A river carries soil and rocks from upstream in its swiftly moving water. This material is dumped at the river mouth, forming this landform.
Some spits grow so large that a river may be forced to change its course to reach the sea. Over thousands of years, the river mouth may move hundreds of metres along the coast and a calm stretch of water behind the spit is formed.
This landform is formed when waves curve around an island close to shore and deposit a bar of sand/sediment on the side of the island closest to the mainland. Eventually, enough material builds up to create a permanent connection between the island and the mainland.
This is the most common type of depositional landform. It is formed when constructive waves carry sand, pebbles and broken coral or shells in their stash and deposit them on the shore.
This landform occurs when a wave-cut notch (formed when waves attack the base of a cliff) collapses. Rubble from the collapsed wave-cut notch is then carried back out to sea by backwash, leaving behind this landform.
Some sections of coastlines are composed of denser and more durable rock than other sections. These can resist the energy of destructive waves for longer than the softer parts, and remain to form this landform- high, rocky outcrops of land.
This landform is one of the most common features of coastlines around the world. They are shaped through a combination of erosion and weathering. Wave action erodes away softer rock, leaving the more durable rock behind.
The softer parts of a coastline wear away more quickly than headlands and become this landform.
As the soft rock of arches is eroded by the power of destructive waves, the rock at the top of the arches eventually fall into the sea, leaving behind this landform- tall, vertical columns of rock.
This landform occurs when waves attack the sides of headlands and island (a process known as refraction), wearing away at weak spots in the rock. This eventually causes small openings to form which become larger over time.
As waves erode the back of a cave, they may penetrate right through the headland, producing this landform. Waves continue to pass through this landform, eroding the sides and the top.
Wind can pick up individual grains of dry sand, and then inland from the coast. As the grains move, they may be trapped by an obstruction (eg. vegetation) or they may collect in areas sheltered from the wind. As the sand piles higher, it forms this landform. Plants grow on this landform, holding them together.
Swash is the water that falls forward and moves up the shore.
The backwash is the water that runs back from the land to the ocean after the swash.
A destructive wave tends to remove material from a coast and is associated with erosion. They crash into the shoreline taking big chunks out of the land and erode the beach. This wave occurs when the backwash is strong than the swash therefore the backwash is able to carry materials out.
A constructive wave is associated with deposition, it is when the sea loses energy and drops its load of sand, rock particles and pebbles, that it has been carrying. Constructive waves occur when the swash is stronger than the backwash. They tend to deposit material on beaches when they crash.
Spit, sand dune, tombolo, sand bar, beach
Wave-cut platform, stack, stump, gorge, bay, arch, cave, cliff, headland
Large boulders that works in a similar fashion to sea walls but are instead permeable
Hard Mangement Strats
Vertical/sloping structures built along the shoreline to stop erosion
Wooden and/or concrete barriers perpendicular(right angled) to the beach, stop long shore drift in the sense that they break the waves and do not allow for the backwash to occur
An artifical offshore structure protecting a harbour anchorage or marina basin from water ways
Coastal Landforms (Erosional)
Wave Cut PLatform
Coastal Landforms (Depositional)
Soft Mangement Strats
Beach Reshaping and Nourishment
Constructive Waves (Deposition)
Swash is weaker than the backwash, creates the depositional landforms
Destructive Waves (Erosional)
Swash stronger than backwash, creates cliffs, caves, archs etc.
Longshore Drift (Transportation)
When the constant action of backwash swash carries material to another side of the beach, creating a narrow area and a wider area
a small hole is created on the coast, this hole then slowly becomes bigger, finally, the destructive waves can enter and shape the roof, walls and ceiling, giving us a cave
When the destruvtive waves erode the back/headland of the cave, leaving a empt strutcture, an arch
When the destructive waves erode the top of an arch leaving 2 pillars of rock a.k.a 2 stacks
when the softer rock of the coast is eroded and the sedimentry/harder rock is left behind
when loose sand is blown from the dunes to back further waway
when contructive waves leave the material and form a struture in the water, which curves due to the rips
It is formed when sand is moved by the
long shore and deposited at the
entrance of the bar
-The deposits accumulate forming a
The continued deposition the sandbar
lengthens eventually forming a bay bar
-The bay bar separates part of the sea
water from the open sea. The enclosed
sea water is the Lagoon
when a spit connects to a island forming a bridge
sand dunes and cliff as natural defense from the sea
replacement of sand/pebbles on eroding beaches