coasts

where are concordant and discordant coasts

concordant - dorset

discordant - holderness

dalmatian coast (croatia)

- narrow limestone concordant islands parallel to coast

- folded up ridges (anticlines) and folded down valleys (synclines)

haff coasts

long sediment ridges topped by sand dunes run parallel to the coast creating lagoons

low vs high angle of seaward dip

high angle (45°+) = low angled slope which is vulnerable to rock slides and one rock layer

low angle (-45°) = steep profile vulnerable to rock fall, overhanging rocks

bedrock lithology

igneous (eg granite in scottish highlands) - interlocking crystalline layers, few faults, highly resistant, do not react with acids

metamorphic (eg slate in wales) - recrystallised rock through heat and pressure so still resistant but no interlocking layers, squishy

sedimentary (eg sandstone, limestone) - heavily jointed and formed through compaction of pieces of rock, clastic

unconsolidated sediment (eg boulder clay at holderness) - very weak and easily eroded 2-10 metres per year

permeable rocks

- porous

- heavily jointed

- easily weathered

pioneer plants

- first plants to colonise a coastline

- leads to plant succession which is different plant communities colonising an area over time

psammosere

swash aligned coasts

wave crests approach parallel to the coast, so there is limited longshore movement of sediment

drift aligned coasts

wave crests break at an angle to the coast, so there is consistent longshore drift and the generation of elongated depositional features

backshore, foreshore, nearshore, offshore

backshore - above the influence of waves

foreshore - intertidal surf zone

nearshore - wave breaker zone

offshore - affected only by wave action due to major storm events

estuarine coastline

mud flats which are exposed at low tide and gradually transition from land to sea

primary coasts

dominated by land based processes such as deposition at the coast from rivers or new coastal land formed from lava flows

secondary coasts

coast formed by marine action because of changes in the ocean, such as the creation of barrier islands or coral reefs

fault

fracture created with displacement

joint

fracture created with displacement

halophytes

plants that tolerate salty sea water

xerophytes

plants that tolerate dry conditions

storm surge

causes rapid erosion and flooding at the coastline by high pressure causing seawater to pile up