Hurst castle spit Flashcards
What is the location of Hurst castle spit?
Hurst Castle spit is located in Christchurch bay and was formed as a result of longshore drift. It reaches 2 kilometres out into the sea.
Explain the sediment and sand at Hurst Castle spit.
The light brown, flint gravel is present in most of the cliffs as 2 or 3 m thick, and has originated from long-shore drift from the supply cliffs of Highcliffe, Barton-on-Sea and Hordle Cliff. 300,000 cubic metres of shingle from the Shingles Bank was added to the beach as a defence mechanism and much of this can now been seen as a different layer of material at the beach crest. This dredged shingle is very sandy and poorly sorted.
How are spits often formed, and what does this mean in the case of Hurst Castle spit.
Spits are often formed when there is a suddenly drastic change in direction of the coast, and in the case of the Hurst Castle spit, it was the change in direction to the south-east of Milford-on-Sea.
How was Hurst Castle spit formed?
The Hurst Castle spit was formed by longshore drift, when the direction change of the coast allowed deposited shingle to form the spit; the ocean currents are stronger than the drift resulting in a curved end to the spit.
The natural spit is made up of the Hurst beach made up of the sediment pushed up by the south-westerly wave dominant direction.
What does Hurst castle spit protect?
The spit protects are large area of the ‘Keyhaven Marches”, yet the marshes are being eroded quite rapidly.
What are some Key features of Hurst castle?
Hurst castle spit contains mudflats at low tide, inside the spit. The colonisation of mud banks by halophytic (slat loving plants), which trap more sediment has occurred directly behind the spit. The Keyhaven salt marsh has formed closer to shore behind the spit, in an area that is most protected by the spit.
Describe the Marshes at Hurst Castle Spit.
Marshes have formed behind the spit, this is because spit shelters the marsh for sediment accumulation. Eel grass grows there sheltered from the strong winds, which stabilises the area by trapping sediment. As other plants grow such as glass, and in time, decompose to contribute to the organic matter
