What is a Spit Landform?
Spit is a landform in geography that is created from the deposition of the sand by the tide movements. One end of the spit remains attached to the mainland while the other end is open out in the water. It is narrow and elongated. Also known as sandspit, this type of landform is found off the coasts or the lake shores.
How Are Spits Formed?
Spits are usually formed when re-entrance takes place by the longshore drift process from longshore currents. When waves at an oblique angle meet the beach, drift occurs. There is a deposit of sediment in a narrow strip in zigzag pattern moving down the beach. The same waves also cause longshore currents that complement the formation of the spit.
At the re-entrance, the longshore current spreads out or dissipates and not being able to carry the full load, drops much of the sediment which is called deposition. The longshore or littoral drift continues to transport sediment with the help of this submerged bar of deposit into the open waters alongside the beach in the direction the waves are breaking.
This process forms an above-water spit. The formation of spit will continue out into the sea until the water pressure obstructs in the deposition of sand. As it grows, it becomes stable and often fertile; vegetation starts to grow and supports habitation.
The refraction of the wave can occur at the end of a spit. It carries sediment around the end and forms a hook or recurved spit. Refraction of wave in multiple directions may create a complex spit. If waves arrive in a direction that is not oblique along the spit, the growth of the spit will stop, shorten, or eventually destroy.
The sediments from a variety of sources including rivers and eroding bluffs build spits, and the resulting changes affect spits and other coastal landforms. The sea and wind erode these landforms, but if there is a constant supply of sediment from longshore drift, their existence continues. Depending on the supply of sediment or any interruption occurring in the supply eventually create other landforms like an island or a bar, or a lagoon or a tombolo.
7 Most Famous Spits On Our Planet
1. Spurn Point, United Kingdom
Spurn Point or Spurn Head is a well-known spit in the United Kingdom at the mouth of the Humber River. It is one of the most amazing features of Britain’s coastline. Located 46 m across, on the tip of the coast of the East Riding of Yorkshire, it extends out into the sea for 5.5 km across the Humber Estuary.
The area which is about 280 acres has sand and shingle banks held together by marram grass and sea buckthorn. Spurn is relatively a small, narrow place, however, considered as a wildlife haven for migrant birds, roe deer, lizards, and numerous species of insects. As it is open to the ravages of the North Sea, it has a very delicate ecosystem. It’s also an ideal place for birdwatchers.
2. Farewell Spit, New Zealand
It is the longest sand spit located in New Zealand, stretching for about 26 km above sea level and 6 km more underwater. From the island’s northernmost point Cape Farewell, situated at the northern end of the South Island of New Zealand, it moves eastwards.
It is made from the fine golden sand and is large enough to have its dunes. On the northern side, dunes are steeper and unstable, whereas the southern side facing the Golden Bay is more stable and covered with vegetation, mostly. Here as the tide can recede as much as 7 km, it exposes around 80 sq km of mud flats which is a fertile feeding ground for the sea birds in thousands in the area, but at the same time also a trap for the frequently stranded whales.
The New Zealand Department of Conservation administers the spit as wildlife and sea bird reserve. Other than a small area at the base of the spit, it is closed for public except through organized tours. However, a lighthouse is there at the end of the spit that can be visited by tourists.
3. Arabat Spit, Azov
Located in the Sea of Azov, it is the longest spit in the world about 110 km in length. It is a very young spit formed by processes of sedimentation around 1100–1200 AD. Located between Henichesk town on the north and the north-eastern Crimes shores on the south, it gets separated from Henichesk by the Henichesk Strait.
Until 1835 it was wild, and only a road and five stations were built for postal delivery. Later three military and 25 rural settlements and a village called Arabat appeared on the spit in the 19th century. Some 235 rural people lived there whose occupation was mainly fishery, farming and salt production.
The vast areas of Sivash lagoons consist of highly saline water, which is the primary source of salt in the region. During the 19th century, nearly 24,000 tonnes of salt were produced every year alone on the Arabat Spit.
4. Curonian Spit, Russia
This one is a curved, thin sand-dune spit of 98 km in length which divides the Curonian Lagoon from the coast of Baltic Sea. From the Sambian Peninsula on the south, it stretches to its northern tip next to a narrow strait, across which the port city of Klaipėda on the mainland of Lithuania lies.
The northern Curonian Spit peninsula stretched at 52 km long belongs to Lithuania, and the rest is forming part of Kaliningrad Oblast, Russia. The width of the spit ranges between least as 400 meters in Russia to the highest as 3,800 meters in Lithuania. The highest drifting dunes of Europe can be found in this spit, and their average height varies from 35 m to 60 m sometimes.
Birds, 10 to 20 million in numbers fly over the spit during spring and fall migrations while many also pause to rest or breed there. The migratory waterfowl are frequently seen here. There are several towns, including the largest Nida in Lithuania, which is a popular holiday resort and frequently visited by Lithuanian and German tourists.
5. La Manga del Mar Menor, Spain
La Manga del Mar Menor which is also known as La Manga is a seaside 22 km long and 100 m wide spit on an average in the Region of Murcia, Spain. Until the 1960s, it was untouched and after that La Manga was discovered as a tourist resort. This spit underwent rapid urbanization of the area, including the development of infrastructure for tourists.
At present, it is densely populated and divides the Mediterranean Sea from the Mar Menor (Minor Sea) lagoon. La Manga is cut off by natural channels from Cabo de Palos to the Punta del Mojón that keeps the two seas in contact with each other.
6. Dungeness Spit, Washington
This natural sand spit in the US is the longest that stretches up to 8.9 km. Jutting out from the Olympic Peninsula (northern edge) in Clallam County (north-eastern part), Washington, USA, the Dungeness Spit meets the Juan de Fuca Strait. It encloses a body of water known as Dungeness Bay.
The whole spit is within the Dungeness National Wildlife Refuge which is a sanctuary for 41 species of land mammals, eight species of water mammals, and over 250 species of birds. It is also home to the Dungeness Lighthouse. Visitors can hike to the tip including the lighthouse that has been guarding since 1857. However, the extreme tip, such as the Dungeness Bay side of the spit, is closed for public entry for protection of critical wildlife habitat.
7. Homer Spit, Homer
Homer Spit is in Homer, Alaska, and it is home to the very popular Homer Boat Harbor serving up to 1,500 commercial as well as pleasure boats at its peak season in summer. First, it was inhabited by early natives who came there to camp out. Later with the arrival of the Americans, permanent habitation started to grow, including a wharf, a company town, and eventually the harbor which is now vital to the local economy.
The spit includes several attractions such as an artificial fishing hole – ‘The Nick Dudiak Fishing Lagoon,’ hotels, restaurants and campgrounds, and the Salty Dawg Saloon, constructed out of several historic buildings from Homer. On this spit, the road leading to the ocean waters is the world’s longest and takes about 10–15 minutes to cover by car.