Coastal MorphologyCoastal Morphology

• So far we’ve investigated:

• Erosion

• Exposure to Wave Action

• Types of Wave Action

• Sand dunes

• Coastal Features

• Which one overriding factor will govern much of this?

• So far we’ve investigated:

• Erosion

• Exposure to Wave Action

• Types of Wave Action

• Sand dunes

• Coastal Features

• Which one overriding factor will govern much of this?

• Each part of each coastline is reliant upon one factor

• Each part of each coastline is reliant upon one factor

•Geology.• The rock type and structure.• Geologists and Geographers have

been able to draw up classifications of coasts:

•Geology.• The rock type and structure.• Geologists and Geographers have

been able to draw up classifications of coasts:

Transverse CoastsTransverse Coasts

• These develop when the rock strata runs at right angles to the shoreline (Waves that run at right angles to the shore are also know as ????????)

• These develop when the rock strata runs at right angles to the shoreline (Waves that run at right angles to the shore are also know as ????????)

Transverse CoastsTransverse Coasts

• These develop when the rock strata runs at right angles to the shoreline (Waves that run at right angles to the shore are also know as Discordant)

• Harder rock tends to form headlands and the softer rocks bays or havens

• These develop when the rock strata runs at right angles to the shoreline (Waves that run at right angles to the shore are also know as Discordant)

• Harder rock tends to form headlands and the softer rocks bays or havens

Transverse Coastline at SwanageTransverse Coastline at Swanage

Longitudinal CoastsLongitudinal Coasts

• Occurs when rock strata runs Parallel to the coast.

• This type of coastline is also called a ????????

• Occurs when rock strata runs Parallel to the coast.

• This type of coastline is also called a ????????

Longitudinal CoastsLongitudinal Coasts

• Occurs when rock strata runs Parallel to the coast.

• This type of coastline is also called a concordant coastline

• Occurs when rock strata runs Parallel to the coast.

• This type of coastline is also called a concordant coastline

Longitudinal or Concordant CoastLongitudinal or Concordant Coast

Longitudinal CoastsLongitudinal Coasts

• Local rocks in the Lulworth Area are hard on the outside and weaker on the inside forming coves

• Local rocks in the Lulworth Area are hard on the outside and weaker on the inside forming coves

Classification of CoastsJohnson 1919Classification of CoastsJohnson 1919

Valentin 1952Valentin 1952

Shepard 1963Shepard 1963

• PRIMARY - The configuration of these coasts develops from non-marine processes. They have not been significantly altered since the last rise of sea level Influence of the sea has been minimal (Shaped by sub aerial erosion and partly drowned by postglacial rise of sea level. )

• SECONDARY - Shaped primarily by marine agencies or by marine organisms. May or may not have been primary coasts before being shaped by marine forces (Reshaping of the coastline by marine forces, primarily wave action. Other erosive forces such as karst erosion may play a role)

• This again was seen as over simplistic and generalised

• PRIMARY - The configuration of these coasts develops from non-marine processes. They have not been significantly altered since the last rise of sea level Influence of the sea has been minimal (Shaped by sub aerial erosion and partly drowned by postglacial rise of sea level. )

• SECONDARY - Shaped primarily by marine agencies or by marine organisms. May or may not have been primary coasts before being shaped by marine forces (Reshaping of the coastline by marine forces, primarily wave action. Other erosive forces such as karst erosion may play a role)

• This again was seen as over simplistic and generalised

Inmann and Nordstrom 1971Inmann and Nordstrom 1971

Davis 1980Davis 1980• Energy produced Coastlines – Though only

relatively recent it is beginning to gain credibility because it relates directly to the amount of energy expended by different waves on different environments.

• HIGH ENERGY ENVIRONMENTS – e.g. destructive waves breaking on shingle beaches

• LOW ENERGY ENVIRONMENTS – e.g. constructive waves break upon sandy beaches

• PROTECTED ENVIRONMENTS – Where wave action is limited in small sheltered, sea areas.

• Energy produced Coastlines – Though only relatively recent it is beginning to gain credibility because it relates directly to the amount of energy expended by different waves on different environments.

• HIGH ENERGY ENVIRONMENTS – e.g. destructive waves breaking on shingle beaches

• LOW ENERGY ENVIRONMENTS – e.g. constructive waves break upon sandy beaches

• PROTECTED ENVIRONMENTS – Where wave action is limited in small sheltered, sea areas.

Further ReadingFurther Reading

• http://geology.uprm.edu/Morelock/morphol.htm

• Guinness and Nagle (p.293-296) “Advanced Geology Concepts and Cases” Hodder & Stoughton 2005

• D. Waugh. (p.148-152) “Geography An Integrated Approach” Nelson 1995

• http://www.jfk.herts.sch.uk/north_norfolk/excercises/act1.html

• http://www.soton.ac.uk/~imw/bourne.htm

• http://geology.uprm.edu/Morelock/morphol.htm

• Guinness and Nagle (p.293-296) “Advanced Geology Concepts and Cases” Hodder & Stoughton 2005

• D. Waugh. (p.148-152) “Geography An Integrated Approach” Nelson 1995

• http://www.jfk.herts.sch.uk/north_norfolk/excercises/act1.html

• http://www.soton.ac.uk/~imw/bourne.htm