Spits Flashcards
A spit is
a long narrow strip of land that is formed when longshore drift causes the beach to extend out to sea, usually due to a change in direction of the coastline.
How the spit is formed?
When the coast suddenly changes direction, longshore drift continues to deposit material across the river mouth, leaving a bank of sand and shingle sticking out in the sea.
Why would the end of the spit recurve?
Because wave refraction acting on the end of the spit would carry material round into the more sheltered water behind the spit.
Why spit cannot grow across the river estuary?
Because material is also carried seaward by the river
There are 2 types of spits
Simple and compound
Simple spits do not have
minor spits or recurved ridges along their landward edge
Compound spits have
a number of recurved ridges or minor spits, along their landward side
What can form in the sheltered area behind the spit?
salt marshes
Why a salt marsh can form behind the spit?
Due to the sheltered, saline environment
How long and wide is Spurn Head Spit in East Yorkshire?
3.5 miles long and in some places only 50 metres wide
What was the source of sediment for the formation of a Spurn Head Spit?
Dynamic and rapidly eroding Holderness coast in East Yourkshire
Across which rivers estuary spit was formed?
Across river Humber Estuary
Is the spit still changing?
Yes, waves carry material along the peninsula to the tip, continually extending it; as this action stretches the peninsula it also narrows it
Can the sea cut across the spit?
Yes, when the sea cuts across it permanently, everything beyond the breach is swept away, only to eventually reform as a new spit pointing further south.
How often is the cycle of destruction and reconstruction is repeated?
Approximately every 250 years
