4.3a Flashcards
What is the rock type (geology) like on a concordant coastline?
On a concordant coastline, there is typically a front of hard rock (such as granite) which acts as a protective barrier, shielding the softer rock further inland. Sometimes this barrier is punctured, allowing erosive forces to reach inland where it can create coves such as Lulworth cove in dorset
What features are found on a concordant coastline?
Features on a concordant coastline can include coves (where the outer layer of hard rock is penetrated allowing the softer rock further inland to be eroded), cliffs can also be found due to the structure of hard rock which prevents effects like rotational slumping and allows for a more solid face.
What is the rock type like on a discordant coast
Rock types on a discordant coast are varied from hard rocks (such as granite) to softer rocks (such as clay or sand), on a discordant coast bands of differing rock types run perpendicular to the coast
what features are found on a discordant coast?
Discordant coasts occur where bands of different rock types run perpendicular to the coast, different rock types can be less or more resistant to erosion, resulting in differing rates of erosion along the coast. this creates features such as headlands and bays, where large outcrops of hard rock such as granite form headlands while weaker rock is eroded back, forming a bay
What is an example of a headland
Durlston head
What is an example of a bay
Swanage Bay
What are joints? How do they effect erosion?
a joint is a break (fracture) of natural origin in the continuity of either a layer or body of rock that lacks any visible or measurable movement parallel to the surface of the fracture. Air may become trapped in the joints, causing it to become compressed which weakens the cliff and causes erosion. The joint is also a weak point in the rock
What are faults and how do they effect erosion?
Faults are cracks in the earths crust, they can present weak points in the rock that will make them easier to break and/or erode
What is the difference between hard and soft rock? give examples
Hard rocks are hard, strong rocks which are some of the oldest rocks which are resistant to erosion such as granite while soft rocks are rocks which are quite young and soft and easily eroded such as clay. Hard rocks are typically igneous or metamorphic while soft rocks are usually sedimentary
What are the characteristics of headlands and bays?
Headlands are large masses of hard rock which jut out to sea.
