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WAVE DEPOSITION AND LANDFORMS
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Wave Deposition
• Deposition occurs where the accumulation of sand and shingle exceeds its depletion.
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Wave Deposition Landforms
• 1. Beach • Beaches are made up of eroded material that has been transported from elsewhere and deposited by the sea (Shingle or sand). • Constructed by a swash and destroyed by a strong backwash. • E.g Coco, kawe, In Dar es Salaam and Tunza,Avash andMalaika Beaches in Mwanza
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Tunza Beach Mwanza
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Malaika Beach Mwanza
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Coco Beach Dar es Salaam
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2. Dunes
• Immediately landward of the beach are commonly found large, linear accumulations of sand known as dunes.
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Formation of Coastal Dunes
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A Transverse dunes at Veracruz, Mexico
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3. Spit
• A spit is a deposition bar or beach landforms off coasts. • It develops in places where re-entrance occurs, by long shore currents.
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Formation of a spit
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Tombolo
• Tombolo an island is attached to the mainland by a narrow piece of land such as a spit or bar. • It may referred to as a kind of bridge between mainland an off-shore island. • E.g Lumley beach tombolo in Sierra leone, Near Bukakata on the shore of L. Victoria
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Tombolo Formation
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Cuspate foreland/Cuspate Spit
• Is a large triangular deposit of sand or shingle which is terminating seawards. • It is formed as two spits which form towards each other eventually merge.
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Cuspate foreland
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A view of Cuspate Foreland in Chicago, Illinois in US
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Lagoon
• It is a body of calm water enclosed more often near the coastline. • The formation of lagoons may be associated to a cuspate foreland or a bay bar or coral reefs.
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Lagoon Formation
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Blue Lagoon in Coron Palawan Philippines
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Mudflats and Marshes
• A mudflat is a platform of silt and other varieties of alluvium along the coast. • Mudflats may be found at estuaries or in sheltered location behind the bards and spits. • When the mudflat supports vegetation becomes a marsh or a swamp • The nature of vegetations depends on the nature of water e.g. halophytes and magroves flourish in salty waters like the East African Coast.
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Marshes and Mudflats
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Halophytes: Sea Arrowgrass (Triglochin maritimum)
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Water marshes in South London
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Mangrove Forest, Uzi Island, Zanzibar
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Economic Significance of Wave Landform • Tourism • Fishing • Building materials • Research sites • Protection • Habitats for aquatic animals and • Breeding areas • Recreational areas
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Major threats to the world's oceans
• Unsustainable Fishing • Inadequate Protection • Tourism and Development • Shipping • Gas and Oil • Pollution • Aquaculture • Climate change
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Global distributions of contaminants along the coast
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Oil spills: A major marine ecosystem threat
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Gas drilling in Mtwara Tanzania
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Coral Coast
• Read for yourSelf (from the given reference)
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