Geological structure Flashcards
(17 cards)
What is isostatic change?
Land increases or decreases
What is eustatic change?
Sea level changes
What is marine erosion?
Action of waves and erosional processes
What is sub-aerial erosion?
Mass movement and weathering
What is coastal accretion?
Deposition rates are higher than erosion rates
What are discordant coasts?
Alternating bands of hard and soft rock meet at a right angle/perpendicular to the coast (Lulworth cove = alternating headlands and bays)
What are concordant coasts?
Same type of rock runs parallel to the coast (Dalmation and Haff and Lulworth cove)
How do Dalmatian costs form?
Anticlines and synclines run parallel
Formed through tectonic activity
Devensian glacial = flooded synclines leaving anticlines
How do half coastlines form?
Devensian glacial left sand and gravel deposited in the middle of the sea
Afterwards the material deposited nearer the coast by constructive waves making a bay with a lagoon behind it
What does wave refraction refer to?
Changes in the amount of energy reaching the shore = concentrates at headlands and increases erosion
What are strata?
Layers of rock
What are bedding planes?
Horizontal cracks due to pauses in formation
What are joints?
Vertical cracks due to tectonic movement
What are folds?
Strata fold due to pressure/tectonic movement - Lulworth cove
What are faults?
Stress/pressure causes fractures
What are dips?
The angle of the strata - Lulworth cove
What does geological factors include?
Lithology and geological structure
