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Geography Of Samoa
The Samoan archipelago is a chain of 16 islands and numerous seamounts covering in the central Pacific Ocean, South Pacific, south of the equator, about halfway between Hawaii and New Zealand, forming part of Polynesia and of the wider region of Oceania. The islands are Savaiʻi, Upolu, Tutuila, Wallis_(island), ’Uvea, Taʻū, Ofu-Olosega#Ofu, Ofu, Olosega, Apolima, Manono Island, Manono, Nuʻutele, Niulakita, Nuʻulua, Namua, Fanuatapu, Rose Atoll, Manono_Island#Neighbouring_islands, Nu'ulopa, as well as the submerged Vailuluʻu, Pasco banks, and Alexa Bank. Tectonics The Samoan archipelago has many features that are consistent with a plume-driven Hotspot_(geology), hotspot model, including the currently active submarine volcano Vailuluʻu that anchors the eastern extremity. However, the chain's proximity to the northern end of the Tonga trench, and the presence of voluminous young volcanism on what should be the oldest (~5 my) western island Savaiʻi has induced controve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manono Island
Manono is an island of Samoa, situated in the Apolima Strait between the main islands of Savai'i and Upolu, 3.4 km west-northwest off Lefatu Cape, the westernmost point of Upolu. By population, as well as by area, it is Samoa’s third largest island. There are four villages on the island with a total population of 889 (2006 Census). Electricity was only introduced in 1995 and there are several shops with beach fale accommodation for visitors. The boat trip from Upolu island takes about 20 minutes. The neighbouring islands are Apolima, which has a small village settlement and the islet Nu'ulopa. Manono Island is part of the political district Aiga-i-le-Tai. The majority of people in the Aiga-i-le-Tai district live on the 'mainland' at the west end of Upolu island. Dogs of any kind are prohibited on Manono island. Villages The four villages and their populations on Manono Island are #Apai, west (111) #Faleu, south (354) #Lepuia'i, southwest (223) #Salua, north (201) Out of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tonga Trench
The Tonga Trench is an oceanic trench located in the southwestern Pacific Ocean. It is the deepest trench in the Southern hemisphere and the second deepest on Earth after the Mariana Trench. The fastest plate-tectonic velocity on Earth is occurring at this location, as the Pacific plate is being Subduction, subducted westward in the trench. Horizon Deep The deepest point of the Tonga Trench, the Horizon Deep at , is deep, making it the deepest point in the Southern Hemisphere and the second deepest on Earth after the Challenger Deep in the Mariana Trench. It is named for the research vessel RV Horizon, ''Horizon'' of the Scripps Institution of Oceanography, the crew of which found the deep in December 1952. As one of the deepest Hadal zone, hadal trenches, the sediment of the Horizon Deep harbours a community of Nematode, roundworms. A 2016 study found that the abundance of individuals in this community is six times greater than it is at a site on the trench edge at approximate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hotspot (geology)
In geology, hotspots (or hot spots) are volcanic locales thought to be fed by underlying Mantle (geology), mantle that is anomalously hot compared with the surrounding mantle. Examples include the Hawaii hotspot, Hawaii, Iceland hotspot, Iceland, and Yellowstone hotspots. A hotspot's position on the Earth's surface is independent of plate boundary, tectonic plate boundaries, and so hotspots may create a chain of volcanoes as the plates move above them. There are two hypotheses that attempt to explain their origins. One suggests that hotspots are due to mantle plumes that rise as thermal diapirs from the core–mantle boundary. The alternative plate theory (volcanism), plate theory is that the mantle source beneath a hotspot is not anomalously hot, rather the crust above is unusually weak or thin, so that lithospheric extension permits the passive rising of melt from shallow depths. Origin The origins of the concept of hotspots lie in the work of J. Tuzo Wilson, who postulated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexa Bank
Alexa Bank is a seamount in Samoa, northwest of Rotuma. The seamount reaches a depth of below sea level and has the appearance of an atoll with a flat top and steep slopes. Some active coral growth takes place at its top, but if it ever was an active atoll it has now drowned. It was probably formed by the Samoa hotspot 24 million years ago, although older volcanism about 40 million years ago has also been identified. Geology and geomorphology Local Alexa Bank rises to depths of , has an eastward elongated flat top and is long and wide, widening towards the west; such dimensions resemble these of Savaii and Upolu in Samoa. The flat top has some features of an atoll including a raised rim, and it may indeed once have been an atoll. The rim is surrounded by a narrow terrace and in turn encloses a much wider terrace, that surrounds the flat top at an average depth of . The northern and southern flanks are formed by steep scarps, with the eastern slope featuring a terrace at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pasco Banks
The Pasco Banks (also known as Pasco Seamount) refers to a naturally occurring geological and marine formation in the south Pacific Ocean. The Pasco Banks is a long ridge-like seamount that rises from about 200 m to within 30 m of the ocean's surface. Covered in patchy coral reef, it attracts large schools of baitfish, mainly rainbow runner, which in turn are preyed upon by larger predatory fishes. This abundance of fish has made the Pasco Banks a popular and reliable fishing location for hundreds of years. Location The Pasco Banks seamount formation is located 13° 05' 00" S latitude and 174° 25' 00" W longitude in the South Pacific Ocean, roughly halfway between the Polynesian islands of Samoa and Uvea. The seamount that includes the Pasco Banks is part of the Samoan volcanic chain which extends from Tuvalu, Uvea, and Futuna eastward to the submarine volcano Vailulu'u east of the Manu'a islands of American Samoa. While the Samoan volcanic chain results from the pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vailuluʻu
Vailuluu is a volcanic seamount discovered in 1975. It rises from the sea floor to a depth of and is located between Tau and Rose islands at the eastern end of the Samoa hotspot chain. The basaltic seamount is considered to mark the current location of the Samoa hotspot. The summit of Vailuluu contains a 2 km wide, 400 m deep oval-shaped caldera. Two principal rift zones extend east and west from the summit, parallel to the trend of the Samoan hotspot. A third less prominent rift extends southeast of the summit. Eruptions at Vailuluu were recorded in 1973. An earthquake swarm in 1995 may have been related to an eruption from the seamount. Turbid water above the summit shows evidence of ongoing hydrothermal plume activity. Vailuluu may breach the surface of the ocean and officially become an island if a high rate of eruptions continue. Name and research history The seamount was first discovered in 1975 after seismic activity, including earthquakes, was noted in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manono Island
Manono is an island of Samoa, situated in the Apolima Strait between the main islands of Savai'i and Upolu, 3.4 km west-northwest off Lefatu Cape, the westernmost point of Upolu. By population, as well as by area, it is Samoa’s third largest island. There are four villages on the island with a total population of 889 (2006 Census). Electricity was only introduced in 1995 and there are several shops with beach fale accommodation for visitors. The boat trip from Upolu island takes about 20 minutes. The neighbouring islands are Apolima, which has a small village settlement and the islet Nu'ulopa. Manono Island is part of the political district Aiga-i-le-Tai. The majority of people in the Aiga-i-le-Tai district live on the 'mainland' at the west end of Upolu island. Dogs of any kind are prohibited on Manono island. Villages The four villages and their populations on Manono Island are #Apai, west (111) #Faleu, south (354) #Lepuia'i, southwest (223) #Salua, north (201) Out of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rose Atoll
Rose Atoll, sometimes called Rose Island or Motu O Manu ("Bird Island") by people of the Manu'a Islands, is an oceanic atoll within the U.S. territory of American Samoa. An uninhabited wildlife refuge, it is the southernmost point belonging to the United States, about to the east of Tutuila, the principal island of American Samoa. The land area is just at high tide. The total area of the atoll, including lagoon and reef flat amounts to . Just west of the northernmost point is a channel into the lagoon, about wide. There are two islets on the northeastern rim of the reef, larger Rose Island, high, in the east and the non-vegetated Sand Island, high, in the north. The Rose Atoll Marine National Monument that lies on the two outstanding islands of the atoll is managed cooperatively between the U.S. Fish and Wildlife Service and the government of American Samoa. The nearly square atoll is one of the smallest in the world, measuring only . It is also the only atoll of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fanuatapu
Fanuatapu, an uninhabited island, is a volcanic tuff ring off the eastern tip of Upolu Island, Samoa, in central South Pacific Ocean. It is the smallest and easternmost of the four Aleipata Islands, with an area of 15 hectares. It has an automated lighthouse. See also * Samoa Islands * List of islands * Desert island An uninhabited island, desert island, or deserted island, is an island, islet or atoll which lacks permanent human population. Uninhabited islands are often depicted in films or stories about shipwrecked people, and are also used as stereotypes ... References * (includes Fanuatapu) Uninhabited islands of Samoa Volcanoes of Samoa Tuff cones Atua (district) {{Samoa-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Namua
Namu'a is a small, uninhabited island off the east coast of Upolu island in Samoa, in central South Pacific Ocean. It is one of four small islands in the Aleipata Islands grouping. The island is a 10-minute boat ride from Upolu Island, and has beach fale accommodation for visitors. There are several scenic lookout points, and it takes about an hour to walk around the island. See also * Samoa Islands * List of islands * Desert island An uninhabited island, desert island, or deserted island, is an island, islet or atoll which lacks permanent human population. Uninhabited islands are often depicted in films or stories about shipwrecked people, and are also used as stereotypes ... References Uninhabited islands of Samoa Atua (district) {{Samoa-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
