Coastal Landforms (Unit 2, Topic 2)

Question 1

How are Headlands and Bays Formed?

Answer 1

Alternating rock types cause the softer rock to erode. Surrounded by the hard rock due to wave refraction. This creates a headland and a bay

Question 2

How are Wave-Cut Platforms Created?

Answer 2

The base is eroded by water until the top half collapses on-top pushing the cliff back and creating rock pools behind

Question 3

How do Cave, Arches, Stacks, Stumps Form?

Answer 3

An initial crack/fault forms from weathering and is opened further into a cave, the cave is hollowed out to form an arch, the rubble above the arch collapses leaving a stack and a standalone headland. The base of the stack erodes through hydraulic action and the stack falls into the sea where a stump remains

Question 4

How do Blowholes Form?

Answer 4

A crack forms and wave quarrying steeps water further through the rock until the water explodes out of the top of the eroded rock face

Question 5

How does a Geo Form?

Answer 5

Mass movement or slight cracks open up headlands and forms a small cove or geo

Question 6

How do Coves Form?

Answer 6

A small fault in hard rock is eroded and water forces itself through to the soft rock creating an area away from weathering called a cove inside the soft rock

Question 7

What is Deposition?

Answer 7

The sea lays down sediment when there is a reduction in energy resulting from a decrease in velocity or volume of water

Question 8

What are the Ways Marine Deposition Occur?

Answer 8

-When sand and shingle accumulate faster than is removed
-When waves slow following breaking
-As water pauses at the top of the swash before backwash begins
-When water percolates into the beach material as backwash takes it back down the beach

Question 9

What is Aeolian Deposition?

Answer 9

Aeolian Deposition, exposed sand is transported by the wind in 3 ways:

Surface Creep- rolls along the floor
Suspension- sand is lifted away in the air
Saltation- temporarily lifts sand in the air (pushing it along the beach)

Question 10

What is the Process of Longshore Drift?

Answer 10

The prevailing wind drives the sediment and waves up the beach at an angle to perform swash. Gravity pulls the sediment back at a 90 degree angle with backwash. Each time the sediment is deposited and transported in and out of the beach. Deposition occurs when the sediment budget is exceeded. This process pushes sediment across the sediment cell/littoral zone

Question 11

What Factors Affect a Beach Profile?

Answer 11

Wave Energy- Shingle beaches have high energy/ sandy beaches have low energy.

Wave Type- Destructive waves create shallow beaches / constructive beaches create steeper beaches

Sediment type- Shingle beaches steeper as reduce energy by percolation

Longshore Drift- Impacts beach profile

Question 12

What are Swash-Aligned Beaches?

Answer 12

Swash-aligned beaches form where the energy is low. The waves are more parallel to the shore in swash-aligned environments so there is very little horizontal or lateral movement of sediment; found on irregular coastlines where Longshore Drift is impeded

Question 13

What are Drift-Aligned Beaches?

Answer 13

Drift aligned beaches are orientated parallel to the direction of the dominant longshore drift, they can have considerable amounts of sediment transported long distance , develop on regular coastlines where wave direction is at an angle. They can extend out from the coastline due to sudden changes

Question 14

How is a Spit Formed?

Answer 14

Formed by longshore drift, sediment that is pushed past the mainland and deposited where there is a change in the coastline forming a spit that is visible at low tide, hooked ends can form with a change of wind direction

Question 15

How are Bars Formed?

Answer 15

Where spits join across two headlands or bays. They are formed due to longshore drift and if bars enclose bays they form lagoons behind them

Question 16

How are Tombolo’s Formed?

Answer 16

Formed by wave refraction and diffraction and where a spit elongates to join with an island off the mainland

Question 17

How are Barrier Beaches Formed?

Answer 17

An elongated bank of deposited sediment lying parallel to the coastline and not submerged by incoming tides, creating a lagoon behind it

Question 18

How are Sand Dunes Formed?

Answer 18

Sand Dunes are depositional landforms where accumulations of sand are shaped into a mound by wind. They create dynamic ecosystems called psammoseres. They require vegetation to form. They are on constructive coastlines on wide, sandy beaches with large tidal range, strong off-shore winds, lots of debris, no human intervention

Question 19

What is Succession?

Answer 19

The gradual replacement of one plant community by another in an area over time in response to changes in the physical environment

Question 20

What is Primary Succession?

Answer 20

In a place with no soil cover prior to the start of succession

Question 21

What is Secondary Succession?

Answer 21

In a place that has some soil cover but the plant community has been removed

Question 22

What is Plagioclimax?

Answer 22

Where humans halt succession before the climax community is reached

Question 23

What are Mudflats?

Answer 23

Mudflats are a non-permanent feature and are the start to a saltmarsh. They are coastal wetlands found at low energy coastlines, found in estuaries or behind spits, formed by brackish water (salty + fresh water)

Question 24

What are Saltmarshes?

Answer 24

Saltmarshes go through succession to create an ecosystem that is permanent and stabilized by vegetation. They develop when salt tolerant plants stabilize marshes and vegetation succession occurs

Question 25

What is CARR Woodland?

Answer 25

Wet woodland, often low canopied with bulky ground of plants. Found along backwaters and in-between meanders

Question 26

What are the Stages of Salt Marsh Formation?

Answer 26

1.Pioneer Stage
2.Establishment Stage
3.Competition Stage
4.Stablilisation Stage
5.Climax Phase

Question 27

What is the Pioneer Stage of a Saltmarsh?

Answer 27

Pioneer plants take root inside the deposited sand and mud, these are known as halophytes (salt conditioned), the roots will help to stabilize the sand beneath them allowing bigger plants to grow

Question 28

What is the Establishment Stage of a Saltmarsh?

Answer 28

More sediment is deposited on top of the pioneer plants creating a larger marsh by trapping mud that spends more time out of water, plants such as sea aster starts to grow. Creeks will start to drain the marsh

Question 29

What is the Competition Stage of a Satlmarsh?

Answer 29

As the marsh largens more plants that are strong enough to compete for sunlight, water and oxygen grow

Question 30

What is the Stabilization Stage of a Saltmarsh?

Answer 30

More roots stabilize the ground with sediment immersion of water becoming less frequent, less space for new species so survival of the fittest, sea lavender grows here. The height of the marsh is increased through years of decay and soil development

Question 31

What is the Climax Phase of a Saltmarsh?

Answer 31

Lots of plants are able to grow away from the salty conditions especially with a freshwater source. The saltmarsh is very stable and will only submerge under heavy rain, woodland starts to grow at the back end of the marsh.