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75-459: Someshwara Somanatha Temple is situated on the banks of Arabian Sea at the Western Ghats of South India 13 kilometres (8.1 mi) away from Mangalore . The temple is known as Rudrapada Kshetra, and is also a pilgrimage centre for performing Pitrakrayas (last rituals of departed soul). Historically it is said to have been built by Kings of Alupa Dynasty in the 10th century A.D. The temple

150-415: A commensal relationship , for example brittle stars , who climb the coral to get themselves off the seafloor, helping them to catch food particles, or small zooplankton, as they drift by. This is in sharp contrast with the typical deep-sea habitat, where deposit-feeding animals rely on food they get off the ground. In tropical zones extensive coral growth results in the formation of coral atolls late in

225-399: A certain pattern in terms of eruptive activity, first observed with Hawaiian seamounts but now shown to be the process followed by all seamounts of the ocean-ridge type. During the first stage the volcano erupts basalt of various types, caused by various degrees of mantle melting . In the second, most active stage of its life, ocean-ridge volcanoes erupt tholeiitic to mildly alkalic basalt as

300-692: A classic example being the Emperor Seamounts , an extension of the Hawaiian Islands . Formed millions of years ago by volcanism , they have since subsided far below sea level. This long chain of islands and seamounts extends thousands of kilometers northwest from the island of Hawaii . There are more seamounts in the Pacific Ocean than in the Atlantic, and their distribution can be described as comprising several elongate chains of seamounts superimposed on

375-437: A daunting task due to their sheer number. The most detailed seamount mappings are provided by multibeam echosounding ( sonar ), however after more than 5000 publicly held cruises, the amount of the sea floor that has been mapped remains minuscule. Satellite altimetry is a broader alternative, albeit not as detailed, with 13,000 catalogued seamounts; however this is still only a fraction of the total 100,000. The reason for this

450-498: A few have been studied in detail by scientists. Seamounts and guyots are most abundant in the North Pacific Ocean, and follow a distinctive evolutionary pattern of eruption, build-up, subsidence and erosion. In recent years, several active seamounts have been observed, for example Kamaʻehuakanaloa (formerly Lōʻihi) in the Hawaiian Islands . Because of their abundance, seamounts are one of the most common marine ecosystems in

525-405: A global understanding of seamount ecosystems, and the roles they have in the biogeography , biodiversity , productivity and evolution of marine organisms. Possibly the best ecologically studied seamount in the world is Davidson Seamount , with six major expeditions recording over 60,000 species observations. The contrast between the seamount and the surrounding area was well-marked. One of

600-626: A more or less random background distribution. Seamount chains occur in all three major ocean basins, with the Pacific having the most number and most extensive seamount chains. These include the Hawaiian (Emperor), Mariana, Gilbert, Tuomotu and Austral Seamounts (and island groups) in the north Pacific and the Louisville and Sala y Gomez ridges in the southern Pacific Ocean. In the North Atlantic Ocean,

675-464: A number of seamounts are active undersea volcanoes; two examples are Kamaʻehuakanaloa (formerly Lo‘ihi) in the Hawaiian Islands and Vailulu'u in the Manu'a Group ( Samoa ). The most apparent lava flows at a seamount are the eruptive flows that cover their flanks, however igneous intrusions , in the forms of dikes and sills , are also an important part of seamount growth. The most common type of flow

750-420: A particular pattern of growth, activity, subsidence and eventual extinction. The first stage of a seamount's evolution is its early activity, building its flanks and core up from the sea floor. This is followed by a period of intense volcanism, during which the new volcano erupts almost all (e.g. 98%) of its total magmatic volume. The seamount may even grow above sea level to become an oceanic island (for example,

825-486: A publication now in the public domain :  Chisholm, Hugh , ed. (1911). " Arabian Sea ". Encyclopædia Britannica (11th ed.). Cambridge University Press. Sea mount A seamount is a large submarine landform that rises from the ocean floor without reaching the water surface ( sea level ), and thus is not an island , islet , or cliff -rock. Seamounts are typically formed from extinct volcanoes that rise abruptly and are usually found rising from

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900-429: A result of a larger area melting in the mantle. This is finally capped by alkalic flows late in its eruptive history, as the link between the seamount and its source of volcanism is cut by crustal movement. Some seamounts also experience a brief "rejuvenated" period after a hiatus of 1.5 to 10 million years, the flows of which are highly alkalic and produce many xenoliths . In recent years, geologists have confirmed that

975-456: A summit collapse on the northern edge of Vlinder Seamount resulted in a pronounced headwall scarp and a field of debris up to 6 km (4 mi) away. A catastrophic collapse at Detroit Seamount flattened its whole structure extensively. Lastly, in 2004, scientists found marine fossils 61 m (200 ft) up the flank of Kohala mountain in Hawaii . Subsidation analysis found that at

1050-484: A wide variety of tectonic settings, resulting in a very diverse structural bank. Seamounts come in a wide variety of structural shapes, from conical to flat-topped to complexly shaped. Some are built very large and very low, such as Koko Guyot and Detroit Seamount ; others are built more steeply, such as Kamaʻehuakanaloa Seamount and Bowie Seamount . Some seamounts also have a carbonate or sediment cap . Many seamounts show signs of intrusive activity , which

1125-425: Is Bowie Seamount , which has also been declared a marine protected area by Canada for its ecological richness. The study of seamounts has been hindered for a long time by the lack of technology. Although seamounts have been sampled as far back as the 19th century, their depth and position meant that the technology to explore and sample seamounts in sufficient detail did not exist until the last few decades. Even with

1200-413: Is pillow lava , named so after its distinctive shape. Less common are sheet flows, which are glassy and marginal, and indicative of larger-scale flows. Volcaniclastic sedimentary rocks dominate shallow-water seamounts. They are the products of the explosive activity of seamounts that are near the water's surface, and can also form from mechanical wear of existing volcanic rock. Seamounts can form in

1275-587: Is a union territory and is governed by the Union Government of India . The islands form the smallest union territory of India with their total surface area being just 32 km (12 sq mi). Next to these islands are the Maldives islands. These islands are all part of the Lakshadweep-Maldives-Chagos group of islands. Zalzala Koh was an island which was around for only a few years. After

1350-554: Is about 3,862,000 km (1,491,130 sq mi). The maximum width of the sea is approximately 2,400 km (1,490 mi), and its maximum depth is 5,395 metres (17,700 ft). The biggest river flowing into the sea is the Indus River . The Arabian Sea has two important branches: the Gulf of Aden in the southwest, connecting with the Red Sea through the strait of Bab-el-Mandeb ; and

1425-490: Is greatest as a proportion of seafloor area in the North Pacific Ocean, equal to 4.39% of that ocean region. The Arctic Ocean has only 16 seamounts and no guyots, and the Mediterranean and Black seas together have only 23 seamounts and 2 guyots. The 9,951 seamounts which have been mapped cover an area of 8,088,550 km (3,123,010 sq mi). Seamounts have an average area of 790 km (310 sq mi), with

1500-490: Is helped by geochemical exchange between the seamounts and the ocean water. Seamounts may thus be vital stopping points for some migratory animals , specifically whales . Some recent research indicates whales may use such features as navigational aids throughout their migration. For a long time it has been surmised that many pelagic animals visit seamounts as well, to gather food, but proof of this aggregating effect has been lacking. The first demonstration of this conjecture

1575-406: Is hurt by the simple lack of information available. Seamounts are very poorly studied, with only 350 of the estimated 100,000 seamounts in the world having received sampling, and fewer than 100 in depth. Much of this lack of information can be attributed to a lack of technology, and to the daunting task of reaching these underwater structures; the technology to fully explore them has only been around

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1650-604: Is likely to lead to inflation , steepening of volcanic slopes, and ultimately, flank collapse. There are also several sub-classes of seamounts. The first are guyots , seamounts with a flat top. These tops must be 200 m (656 ft) or more below the surface of the sea; the diameters of these flat summits can be over 10 km (6.2 mi). Knolls are isolated elevation spikes measuring less than 1,000 meters (3,281 ft). Lastly, pinnacles are small pillar-like seamounts. Seamounts are exceptionally important to their biome ecologically, but their role in their environment

1725-401: Is named after the ship that struck it in 1973. However, the greatest danger from seamounts are flank collapses; as they get older, extrusions seeping in the seamounts put pressure on their sides, causing landslides that have the potential to generate massive tsunamis . Seamounts can be found in every ocean basin in the world, distributed extremely widely both in space and in age. A seamount

1800-452: Is poorly understood. Because they project out above the surrounding sea floor, they disturb standard water flow, causing eddies and associated hydrological phenomena that ultimately result in water movement in an otherwise still ocean bottom. Currents have been measured at up to 0.9 knots, or 48 centimeters per second. Because of this upwelling seamounts often carry above-average plankton populations, seamounts are thus centers where

1875-468: Is responsible for as much as 95% of ecological damage to seamounts. Corals from seamounts are also vulnerable, as they are highly valued for making jewellery and decorative objects. Significant harvests have been produced from seamounts, often leaving coral beds depleted. Individual nations are beginning to note the effect of fishing on seamounts, and the European Commission has agreed to fund

1950-543: Is technically defined as an isolated rise in elevation of 1,000 m (3,281 ft) or more from the surrounding seafloor, and with a limited summit area, of conical form. There are more than 14,500 seamounts. In addition to seamounts, there are more than 80,000 small knolls , ridges and hills less than 1,000 m in height in the world's oceans. Most seamounts are volcanic in origin, and thus tend to be found on oceanic crust near mid-ocean ridges , mantle plumes , and island arcs . Overall, seamount and guyot coverage

2025-404: Is that often, in the late of stages of their life, extrusions begin to seep in the seamount. This activity leads to inflation, over-extension of the volcano's flanks, and ultimately flank collapse , leading to submarine landslides with the potential to start major tsunamis , which can be among the largest natural disasters in the world. In an illustration of the potent power of flank collapses,

2100-399: Is that the fishes that are targeted over seamounts are typically long-lived, slow-growing, and slow-maturing. The problem is confounded by the dangers of trawling , which damages seamount surface communities, and the fact that many seamounts are located in international waters, making proper monitoring difficult. Bottom trawling in particular is extremely devastating to seamount ecology, and

2175-463: Is that uncertainties in the technology limit recognition to features 1,500 m (4,921 ft) or larger. In the future, technological advances could allow for a larger and more detailed catalogue. Observations from CryoSat-2 combined with data from other satellites has shown thousands of previously uncharted seamounts, with more to come as data is interpreted. Seamounts are a possible future source of economically important metals. Even though

2250-498: The 2009 eruption of Hunga Tonga ). After a period of explosive activity near the ocean surface , the eruptions slowly die away. With eruptions becoming infrequent and the seamount losing its ability to maintain itself, the volcano starts to erode . After finally becoming extinct (possibly after a brief rejuvenated period), they are ground back down by the waves. Seamounts are built in a far more dynamic oceanic setting than their land counterparts, resulting in horizontal subsidence as

2325-738: The Horn of Africa and 380 km (240 mi) south of the Arabian Peninsula. Masirah and the five Khuriya Muriya Islands are islands off the southeastern coast of Oman. There are many major cities and towns in the coast of Arabian Sea. Some of the major cities are Mumbai , Muscat , Karachi , Aden , Salalah , Thiruvananthapuram , Kochi , Kozhikode , Alappuzha , Kollam , Mangalore , Bhavnagar , Jamnagar , Mogadishu , Gwadar , Abu Dhabi , Mundra , Dubai , Kannur , Panaji , Karwar , Udupi , Ratnagiri , Murdeshwar , Veraval , Colombo , Takamaka , and Dhiffushi . The Arabian Sea has one of

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2400-733: The New England Seamounts extend from the eastern coast of the United States to the mid-ocean ridge. Craig and Sandwell noted that clusters of larger Atlantic seamounts tend to be associated with other evidence of hotspot activity, such as on the Walvis Ridge , Vitória-Trindade Ridge , Bermuda Islands and Cape Verde Islands . The mid-Atlantic ridge and spreading ridges in the Indian Ocean are also associated with abundant seamounts. Otherwise, seamounts tend not to form distinctive chains in

2475-805: The Port of Karachi , Port Qasim , and the Gwadar Port in Pakistan, Chabahar Port in Iran and the Port of Salalah in Salalah , Oman . The largest islands in the Arabian Sea include Socotra ( Yemen ), Masirah Island (Oman), Lakshadweep (India) and Astola Island (Pakistan). The countries with coastlines on the Arabian Sea are Yemen, Oman, Pakistan, Iran, India and the Maldives . The International Hydrographic Organization defines

2550-451: The orange roughy ( Hoplostethus atlanticus ). 95% of ecological damage is done by bottom trawling , which scrapes whole ecosystems off seamounts. Because of their large numbers, many seamounts remain to be properly studied, and even mapped. Bathymetry and satellite altimetry are two technologies working to close the gap. There have been instances where naval vessels have collided with uncharted seamounts; for example, Muirfield Seamount

2625-686: The 15th century Portuguese explorer Pero de Covilhăo , reaches depths of 4,400 metres (14,436 ft) and separates the Indus Fan region from the Oman Abyssal Plain, which eventually leads to the Gulf of Oman . The southern limits are dominated by the Arabian Basin , a deep basin reaching depths over 4,200 metres (13,780 ft). The northern sections of the Carlsberg Ridge flank the southern edge of

2700-565: The 2013 earthquake in Pakistan, the mud island was formed. By 2016 the island had completely submerged. Astola Island, also known as Jezira Haft Talar in Balochi , or 'Island of the Seven Hills', is a small, uninhabited island in the northern tip of the Arabian Sea in Pakistan's territorial waters. Socotra, also spelled Soqotra , is the largest island, being part of a small archipelago of four islands. It lies some 240 km (150 mi) east of

2775-765: The Akhdar (Green) Sea, Bahre Fars (Persian Sea), the Ocean Sea, the Hindu sea, the Makran Sea, the sea of Oman; among them Zakariya al-Qazwini , Al-Masudi , Ibn Hawqal and Hafiz-i Abru . They wrote: "The green sea and Indian sea and Persian sea are all one sea and in this sea there are strange creatures." in Iran and Turkey people call it Oman sea. In the Periplus of the Erythraean Sea , as well as in some ancient maps, Erythraean Sea refers to

2850-628: The Arabian Basin, which include a 5,358 metres (17,579 ft) deep point off the northern limit of Calrsberg Ridge. Prominent sea mounts off the Indian west coast include Raman Seamount named after C. V. Raman , Panikkar Seamount, named after N. K. Panikkar , and the Wadia Guyot , named after D. N. Wadia . Sind'Bad Seamount, named after the fictional explorer Sinbad the Sailor , Zheng He Seamount, and

2925-463: The Arabian Basin. The deepest parts of the Arabian Sea are in the Alula-Fartak Trough on the western edge of the Arabian Sea off the Gulf of Aden. The trough, reaching depths over 5,360 metres (17,585 ft), traverses the Gulf of Aden and the Arabian Sea. The deepest known point is in the Arabian Sea limits at a depth of 5,395 metres (17,700 ft). Other significant deep points are part of

3000-513: The Arabian Sea is warming monotonously; it possibly is due to global warming. The intensification and northward shift of the summer monsoon low-level jet over the Arabian Sea from 1979 to 2015, led to increased upper ocean heat content due to enhanced downwelling and reduced southward heat transport. Regional endonyms for the Arabian sea in languages of the coastal regions surrounding it. [REDACTED]   This article incorporates text from

3075-509: The Arabian Sea, with the most important ones being Lakshadweep Islands (India), Socotra (Yemen), Masirah (Oman) and Astola Island (Pakistan). The Lakshadweep Islands (formerly known as the Laccadive, Minicoy, and Aminidivi Islands) is a group of islands in the Laccadive Sea region of Arabian Sea, 200 to 440 km (120 to 270 mi) off the southwestern coast of India. The archipelago

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3150-625: The Gulf of Oman to the northwest, connecting with the Persian Gulf. There are also the gulfs of Khambhat and Kutch on the Indian Coast . The Arabian Sea has been crossed by many important marine trade routes since the 3rd or 2nd millennium BCE. Major seaports include Kandla Port , Mundra Port , Pipavav Port , Dahej Port , Hazira Port , Mumbai Port , Nhava Sheva Port (Navi Mumbai) , Mormugão Port (Goa) , New Mangalore Port and Kochi Port in India,

3225-426: The Indian and Southern Oceans, but rather their distribution appears to be more or less random. Isolated seamounts and those without clear volcanic origins are less common; examples include Bollons Seamount , Eratosthenes Seamount , Axial Seamount and Gorringe Ridge . If all known seamounts were collected into one area, they would make a landform the size of Europe . Their overall abundance makes them one of

3300-520: The Indian subcontinent, which increase winds blowing towards India, bringing up nutrients and reducing oxygen in the Arabian Sea's waters. In winter, phytoplankton suited to low-oxygen conditions turn the OMZ bright green. The wildlife of the Arabian sea is diverse, and entirely unique because of the geographic distribution. Recent studies by the Indian Institute of Tropical Meteorology confirmed that

3375-642: The Mount Error Guyot are some notable sea mounts in western Arabian Sea. Border and basin countries: The Arabian Sea historically and geographically has been referred to with different names by Arabian and European geographers and travelers, including Erythraean Sea , Indian Sea, Oman sea , Erythraean, Persian Sea in para No 34-35 of the Voyage. In Indian folklore, it is referred to as Darya, Sindhu Sagar, Arab Samudra. Arab geographers, sailors and nomads used to call this sea by different names, including

3450-513: The OASIS project, a detailed study of the effects of fishing on seamount communities in the North Atlantic . Another project working towards conservation is CenSeam , a Census of Marine Life project formed in 2005. CenSeam is intended to provide the framework needed to prioritise, integrate, expand and facilitate seamount research efforts in order to significantly reduce the unknown and build towards

3525-675: The average size of seamounts. Nearly 50% of guyot area and 42% of the number of guyots occur in the North Pacific Ocean, covering 342,070 km (132,070 sq mi). The largest three guyots are all in the North Pacific: the Kuko Guyot (estimated 24,600 km (9,500 sq mi)), Suiko Guyot (estimated 20,220 km (7,810 sq mi)) and the Pallada Guyot (estimated 13,680 km (5,280 sq mi)). Seamounts are often found in groupings or submerged archipelagos ,

3600-501: The coast of the sea. It is located between the Karachi towns of Kiamari and Saddar . The Gwadar Port of Pakistan is a warm-water, deep-sea port situated at Gwadar in Balochistan at the apex of the Arabian Sea and at the entrance of the Persian Gulf, about 460 km west of Karachi and approximately 75 km (47 mi) east of Pakistan's border with Iran. The port is located on

3675-750: The crust to the surface. Volcanoes formed near or above subducting zones are created because the subducting tectonic plate adds volatiles to the overriding plate that lowers its melting point . Which of these two process involved in the formation of a seamount has a profound effect on its eruptive materials. Lava flows from mid-ocean ridge and plate boundary seamounts are mostly basaltic (both tholeiitic and alkalic ), whereas flows from subducting ridge volcanoes are mostly calc-alkaline lavas. Compared to mid-ocean ridge seamounts, subduction zone seamounts generally have more sodium , alkali , and volatile abundances, and less magnesium , resulting in more explosive, viscous eruptions. All volcanic seamounts follow

3750-493: The eastern bay of a natural hammerhead-shaped peninsula jutting out into the Arabian Sea from the coastline. Port of Salalah in Salalah, Oman is also a major port in the area. The International Task Force often uses the port as a base. There is a significant number of warships of all nations coming in and out of the port, which makes it a very safe bubble. The port handled just under 3.5m teu in 2009. There are several islands in

3825-425: The effect of seamounts on endemicity. They have , however, been confidently shown to provide a habitat to species that have difficulty surviving elsewhere. The volcanic rocks on the slopes of seamounts are heavily populated by suspension feeders , particularly corals , which capitalize on the strong currents around the seamount to supply them with food. These coral are therefore host to numerous other organisms in

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3900-465: The first two have any potential of being targeted by mining in the next few decades. Some seamounts have not been mapped and thus pose a navigational danger. For instance, Muirfield Seamount is named after the ship that hit it in 1973. More recently, the submarine USS San Francisco ran into an uncharted seamount in 2005 at a speed of 35 knots (40.3 mph; 64.8 km/h), sustaining serious damage and killing one seaman. One major seamount risk

3975-417: The fish that feed on them aggregate, in turn falling prey to further predation, making seamounts important biological hotspots. Seamounts provide habitats and spawning grounds for these larger animals, including numerous fish. Some species, including black oreo (Allocyttus niger) and blackstripe cardinalfish (Apogon nigrofasciatus) , have been shown to occur more often on seamounts than anywhere else on

4050-436: The largest seamounts may reach the sea surface where wave action erodes the summit to form a flat surface. After they have subsided and sunk below the sea surface, such flat-top seamounts are called " guyots " or "tablemounts". Earth's oceans contain more than 14,500 identified seamounts, of which 9,951 seamounts and 283 guyots, covering a total area of 8,796,150 km (3,396,210 sq mi), have been mapped but only

4125-497: The last few decades. Before consistent conservation efforts can begin, the seamounts of the world must first be mapped , a task that is still in progress. Overfishing is a serious threat to seamount ecological welfare. There are several well-documented cases of fishery exploitation, for example the orange roughy ( Hoplostethus atlanticus ) off the coasts of Australia and New Zealand and the pelagic armorhead ( Pseudopentaceros richardsoni ) near Japan and Russia. The reason for this

4200-522: The limits of the Arabian Sea as follows: The International Indian Ocean Expedition in 1959 was among the first to perform hydrographic surveys of the Arabian Sea. Significant bathymetric surveys were also conducted by the Soviet Union during the 1960s. Significant features in the northern Arabian Sea include the Indus Fan , the second largest fan system in the world. The De Covilhao Trough, named after

4275-516: The most common, and least understood, marine structures and biomes on Earth, a sort of exploratory frontier. Most seamounts are built by one of two volcanic processes, although some, such as the Christmas Island Seamount Province near Australia, are more enigmatic. Volcanoes near plate boundaries and mid-ocean ridges are built by decompression melting of rock in the upper mantle . The lower density magma rises through

4350-470: The ocean floor. Marine mammals , sharks , tuna , and cephalopods all congregate over seamounts to feed, as well as some species of seabirds when the features are particularly shallow. Seamounts often project upwards into shallower zones more hospitable to sea life, providing habitats for marine species that are not found on or around the surrounding deeper ocean bottom. Because seamounts are isolated from each other they form "undersea islands" creating

4425-470: The ocean makes up 70% of Earth's surface area, technological challenges have severely limited the extent of deep sea mining . But with the constantly decreasing supply on land, some mining specialists see oceanic mining as the destined future, and seamounts stand out as candidates. Seamounts are abundant, and all have metal resource potential because of various enrichment processes during the seamount's life. An example for epithermal gold mineralization on

4500-536: The primary ecological havens on the seamount is its deep sea coral garden, and many of the specimens noted were over a century old. Following the expansion of knowledge on the seamount there was extensive support to make it a marine sanctuary , a motion that was granted in 2008 as part of the Monterey Bay National Marine Sanctuary . Much of what is known about seamounts ecologically is based on observations from Davidson. Another such seamount

4575-399: The right technology available, only a scant 1% of the total number have been explored, and sampling and information remains biased towards the top 500 m (1,640 ft). New species are observed or collected and valuable information is obtained on almost every submersible dive at seamounts. Before seamounts and their oceanographic impact can be fully understood, they must be mapped,

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4650-584: The rough country in the southern Arabian Peninsula was significant, and the Egyptian Pharaohs built several shallow canals to service the trade, one more or less along the route of today's Suez Canal , and another from the Red Sea to the Nile River , both shallow works that were swallowed up by huge sand storms in antiquity. Later the kingdom of Axum arose in Ethiopia to rule a mercantile empire rooted in

4725-439: The same biogeographical interest. As they are formed from volcanic rock , the substrate is much harder than the surrounding sedimentary deep sea floor. This causes a different type of fauna to exist than on the seafloor, and leads to a theoretically higher degree of endemism . However, recent research especially centered at Davidson Seamount suggests that seamounts may not be especially endemic, and discussions are ongoing on

4800-737: The sea around the rough inland terrain features to its north. These routes usually began in the Far East or down river from Madhya Pradesh , India with transshipment via historic Bharuch (Bharakuccha), traversed past the inhospitable coast of modern-day Iran, then split around Hadhramaut , Yemen into two streams north into the Gulf of Aden and thence into the Levant , or south into Alexandria via Red Sea ports such as Axum . Each major route involved transhipping to pack animal caravan , travel through desert country and risk of bandits and extortionate tolls by local potentates. This southern coastal route past

4875-720: The seafloor is Conical Seamount, located about 8 km south of Lihir Island in Papua New Guinea. Conical Seamount has a basal diameter of about 2.8 km and rises about 600 m above the seafloor to a water depth of 1050 m. Grab samples from its summit contain the highest gold concentrations yet reported from the modern seafloor (max. 230 g/t Au, avg. 26 g/t, n=40). Iron - manganese , hydrothermal iron oxide , sulfide , sulfate , sulfur , hydrothermal manganese oxide , and phosphorite (the latter especially in parts of Micronesia) are all mineral resources that are deposited upon or within seamounts. However, only

4950-416: The seafloor to 1,000–4,000 m (3,300–13,100 ft) in height. They are defined by oceanographers as independent features that rise to at least 1,000 m (3,281 ft) above the seafloor, characteristically of conical form. The peaks are often found hundreds to thousands of meters below the surface, and are therefore considered to be within the deep sea . During their evolution over geologic time,

5025-475: The seamount moves with the tectonic plate towards a subduction zone . Here it is subducted under the plate margin and ultimately destroyed, but it may leave evidence of its passage by carving an indentation into the opposing wall of the subduction trench. The majority of seamounts have already completed their eruptive cycle, so access to early flows by researchers is limited by late volcanic activity. Ocean-ridge volcanoes in particular have been observed to follow

5100-529: The seamount's life. In addition soft sediments tend to accumulate on seamounts, which are typically populated by polychaetes ( annelid marine worms ) oligochaetes ( microdrile worms), and gastropod mollusks ( sea slugs ). Xenophyophores have also been found. They tend to gather small particulates and thus form beds, which alters sediment deposition and creates a habitat for smaller animals. Many seamounts also have hydrothermal vent communities, for example Suiyo and Kamaʻehuakanaloa seamounts. This

5175-678: The smallest seamounts found in the Arctic Ocean and the Mediterranean and Black Seas; whilst the largest mean seamount size, 890 km (340 sq mi), occurs in the Indian Ocean . The largest seamount has an area of 15,500 km (6,000 sq mi) and it occurs in the North Pacific. Guyots cover a total area of 707,600 km (273,200 sq mi) and have an average area of 2,500 km (970 sq mi), more than twice

5250-462: The trade with Europe via Alexandria. Jawaharlal Nehru Port in Mumbai is the largest port in the Arabian Sea, and the largest container port in India. Major Indian ports in the Arabian Sea are Mundra Port , Kandla Port , Nava Sheva , Kochi Port , Mumbai Port , Vizhinjam International Seaport Thiruvananthapuram and Mormugão . The Port of Karachi , Pakistan's largest and busiest seaport lies on

5325-498: The whole area of the northwestern Indian Ocean, including the Arabian Sea. The Arabian Sea has been an important marine trade route since the era of the coastal sailing vessels from possibly as early as the 3rd millennium BCE, certainly the late 2nd millennium BCE through the later days known as the Age of Sail . By the time of Julius Caesar , several well-established combined land-sea trade routes depended upon water transport through

5400-448: The world's three largest oceanic oxygen minimum zones (OMZ), or “dead zones,” along with the eastern tropical North Pacific and the eastern tropical South Pacific. OMZs have very low levels of oxygen , sometimes so low as to be undetectable by standard equipment. The Arabian Sea's OMZ has the lowest levels of oxygen in the world, especially in the Gulf of Oman. Causes of the OMZ may include untreated sewage as well as high temperatures on

5475-453: The world. Interactions between seamounts and underwater currents, as well as their elevated position in the water, attract plankton , corals , fish, and marine mammals alike. Their aggregational effect has been noted by the commercial fishing industry , and many seamounts support extensive fisheries. There are ongoing concerns on the negative impact of fishing on seamount ecosystems, and well-documented cases of stock decline, for example with

5550-822: Was published in 2008. The effect that seamounts have on fish populations has not gone unnoticed by the commercial fishing industry . Seamounts were first extensively fished in the second half of the 20th century, due to poor management practices and increased fishing pressure seriously depleting stock numbers on the typical fishing ground, the continental shelf . Seamounts have been the site of targeted fishing since that time. Nearly 80 species of fish and shellfish are commercially harvested from seamounts, including spiny lobster (Palinuridae), mackerel (Scombridae and others), red king crab ( Paralithodes camtschaticus ), red snapper ( Lutjanus campechanus ), tuna (Scombridae), Orange roughy ( Hoplostethus atlanticus ), and perch (Percidae). The ecological conservation of seamounts

5625-536: Was under the Administrative rule of Kadambas of Banavasi , and Choula Kings of Ullala of the 12th century A.D. The two inscriptions found in the temple says that it was renovated in the 15th century A.D. at the time of Vijayanagara King Immadi Devaraya by Rajaguru Sree Kriyashaktri Devavodeya. This article about an Indian Hindu place of worship is a stub . You can help Misplaced Pages by expanding it . Arabian Sea The Arabian Sea's surface area

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