2.2 Flashcards
How does dipping affect the rate of erosion?
Dip of coast determines overhang
Overhang determines stability of cliff
Affects rate of erosion
How does folding affect erosion?
Faults may be created within the rock when folding occurs
Faults may be exploited
Faster erosion
How does jointing affect rate of erosion?
Joints provide weaknesses within rock which can easily be exploited
Can be further weakened by erosional processes
Rate of erosion is higher
How does faulting affect rate of erosion?
Allows rock to be more easily eroded by marine processes
Increased rate of erosion
What is the bottommost strata on the North Antrim Coast?
Sandstone/Mudstone/Limestone
What is the top strata at the North Antrim Coast?
Glacial till
Deposited on synclines
What is the second bottommost strata at the North Antrim Coast?
Coal
From when this part of coast was at the equator (continental drift)
What is the third bottommost strata at the North Antrim Coast?
- Chalk
- Formed when sea level rose, dead coccoliths settled on floor
- When sea level fell, was exposed to erosion by rivers
What is the 4th bottommost strata at the North Antrim Coast?
- Originally Basalt
- Caused by lava spreading out on top of chalk layer
- Especially in river valleys
- Basalt is weathered into laterite
- Laterite soil is left today
What is the 5th bottommost strata at the North Antrim Coast?
- Basalt flows over lower basalt layer,
- Cools into hexagonal columns
- Is eroded again
What is the 6th bottommost strata at the North Antrim Coast? (2nd highest)
- Third basaltic layer flows over second
- surface is eroded by glaciers
How do tectonic play a part at the North Antrim Coast?
Folded layers into synclines and anticlines
What is glacial till?
Eroded material carried down by glaciers
What is the chalk here made of?
Fossilised coccoliths
What is part of geological structure of a cliff?
- Dip
- Faulting
- Folding