coastal landscape development Flashcards
how are beaches formed?
constructive waves deposit sediment on the shore
shingle beaches
steep angles
larger sediment
sand beaches
wide and flat
formed from smaller particles
where do spits form?
where the coastline suddenly changes direction e.g river mouth
how dospits form?
longshore drift deposits material across river mouth leaving sand a shingle sticking out to sea
simple spit
a straight spit that grows out roughly parallel to the coast is called a simple spit
how does the wind affect a spit?
occasional changes to dominant wind leaves to spit having recurved ends
over time several recurved ends may be abandoned as waves return to their original direction
compound spit
a spit that has multiple recurved ends
what forms behind a spit?
sheltered from waves
mudflats and saltmarshes
how are bars formed?
when a spit joins two headlands together
occurs across a bay or river mouth
what forms behind a bar?
a lagoon
how are offshore bars formed?
sea level rises meaning material moves towards the coast
these remain partly submerged
how are tombolos formed?
bar that connects shore to an island
what are barrier islands?
long narrow islands of sand or gravel that runs parallel to the shore and is detached from it
how are barrier islands formed?
formed after the last ice age
ice melt caused rapid sea level rise. Rising water flooded land behind beaches and transported sand offshore where it was deposited in shallow water forming island
