Landforms of Coastal Areas (78-80)

waves are caused by

wind play on the sea’s surface

shoreline of emergence

land is rising, water is becoming shallower

offshore bar

submarine bar built up above the water’s surface

lagoon

protected waters that lie behind an offshore bar

raised beach

a beach area formerly at sea level, now above it due to isostatic rebound

shoreline of submergence

land is sinking, water is rising

What is good about shorelines of emergence?

flat land good for development

what is bad about shorelines of emergence?

difficult for commercial shipping because of offshore bars and few deep water harbours for ports

ria coastline

long, branching inlets representing drowned river valleys

fjord

drowned u-shaped valley

spit

long, narrow bar of sand pointing in direction of current

when do spits occur?

tidal flow/ wave action runs parallel to the coast

what happens behind spits? (potentially)

Rivers which reach the coast will accumulate alluvium.

tombolo

sand bar linking island to main land

bay mouth bar

spit goes all the way across a bay

What is good about shorelines of submergence?

natural harbours

What is difficult about shorelines of submergence?

rough terrain hard to settle in and cross.

coral reef

corals

produce a skeleton of calcium carbonate which becomes the foundation for new corals can grow resulting in continous growth of the coral reef

eg of coral reef

great barrier reef

ideal conditions for coral

warm, tropical waters

atoll

pacific circular reef enclosing a lagoon

longitudinal coastline

folded mountains are parallel to the coastline