Aleutian Islands | Geology Page Aleutian Islands tweet Convergent Boundary – Aleutian Islands The Aleutian Trench (or Aleutian Trough) is a subduction zone and oceanic trench which runs along the southern coastline of Alaska and the adjacent waters of northeastern Siberia off the coast of Kamchatka Peninsula. It is classified as a “marginal trench” in the east as it runs along the margin of the continent. The trench gives rise to the island arc Aleutian Islands where it runs through the open sea. The trench extends for 3,400 km from a triple junction in the west with the Ulakhan Fault and the northern end of the Kuril-Kamchatka Trench, to a junction with the northern end of the Queen Charlotte Fault system in the east. The Aleutian Trench is a convergent plate boundary. The trench forms part of the boundary between two tectonic plates. Here, the Pacific Plate is being subducted under the North American Plate at an angle of nearly 45 degrees. The rate of closure is 3in. (8 cm) per year.

The Aleutian Islands are a chain of 14 large volcanic islands and 55 smaller ones, forming part of the Aleutian Arc in the Northern Pacific Ocean, occupying an area of 6,821 sq mi (17,666 km²) and extending about 1,200 mi (1,900 km) westward from the Alaska Peninsula toward the Kamchatka Peninsula, marking a line between the Bering Sea and the Pacific Ocean. Crossing longitude 180°, they are the westernmost part of the United States . Nearly all the archipelago is part of Alaska and usually considered as being in the “Alaskan Bush”, but at the extreme western end the small, geologically related, and remote Commander Islands are in Russia. The islands, with their 57 volcanoes, are in the northern part of the Pacific Ring of Fire. The Alaska Marine Highway (a ferry service) passes through the islands. The north side of the trench slopes 3°–4° and the south side l°–4°. This process has created the Aleutian Arc.

The deepest part of the Aleutian trench has been measured at 7,822 metres (25,663 ft) at 51.21°N, 174.83°E., located about 145 km SSW of Buldir Island. North of the trench, a string of volcanoes and associated islands have formed where melting of the crust has been caused by the descending plate beneath them. Center pressure: 10762psi (732atm), 74 MPa (732atm) Metric units.[ Variations in total magnetic intensity (residual) of more than 600 γ were found in the center of the trench and more than 1100 γ on the southern flank.

More Information About : USA Geography Quizzes - Fun Map Games ï¿½ The Aleutian Islands (possibly from Chukchi aliat, "island") are a chain of more than 300 small volcanic islands forming an island arc situated in the Northern Pacific Ocean, occupying an area of 6,821 sq mi (17,666 sq km) and extending about 1,200 mi (1,900 km) westward from the Alaska Peninsula toward the Kamchatka Peninsula. Crossing longitude 180°, they are the westernmost part of the United States (and technically also the easternmost). Nearly all of the archipelago is part of Alaska and usually considered as being in the "Alaskan Bush", but the extreme western end is in Russia. The islands, with their 57 volcanoes, are located in the northern part of the Pacific Ring of Fire. The islands, known before 1867 as the Catherine Archipelago, comprise four groups— the Fox, Andreanof, Rat and Near Islands.

They are all located between 52 degrees and 55 degrees North latitude and 172 degrees East and 163 degrees West longitude. The axis of the archipelago near the mainland of Alaska has a southwest trend, but near the 129th meridian its direction changes to the northwest. This change of direction corresponds to a curve in the line of volcanic fissures which have contributed their products to the building of the islands. Such curved chains are repeated about the Pacific Ocean in the Kuril Islands, the Japanese chain and in the Philippines. All these island arcs are at the edge of the Pacific Plate and experience lots of seismic activity, but are still habitable; the Aleutians lie between the Pacific and North American tectonic plates. The general elevation is greatest in the eastern islands and least in the western. The island chain is really a western continuation of the Aleutian Range on the mainland. The great majority of the islands bear evident marks of volcanic origin, and there are numerous volcanic cones on the north side of the chain, some of them active; many of the islands, however, are not wholly volcanic, but contain crystalline or sedimentary rocks, and also amber and beds of lignite.

The coasts are rocky and surf-worn, and the approaches are exceedingly dangerous, the land rising immediately from the coasts to steep, bold mountains. Breaking news on Aleutian Islands, AK, US - breakingnews.com Download the free Breaking News app for faster updates, alerts and live video. Synopsis Photo: Wikipedia The Aleutian Islands (/əˈluːʃən/; possibly from Chukchi aliat, "island") are a chain of 14 large volcanic islands and 55 smaller ones belonging to both the United States and Russia. They form part of the Aleutian Arc in the Northern Pacific Ocean, occupying an area of 6,821 sq mi (17,666 km2) and extending about 1,200 mi (1,900 km) westward from the Alaska Peninsula toward the Kamchatka Peninsula in Russia, and mark a dividing line between the Bering Sea to the north and the Pacific Ocean to the south.

Crossing longitude 180°, at which point east and west longitude end, the archipelago contains both the westernmost part of the United States by longitude (Amatignak Island) and the easternmost by longitude (Semisopochnoi Island). The westernmost U.S. island in real terms, however, is Attu Island, west of which runs the International Date Line. While nearly all the archipelago is part of Alaska and is usually considered as being in the "Alaskan Bush", at the extreme western end, the small, geologically related Commander Islands belong to Russia. The islands, with their 57 volcanoes, are in the northern part of the Pacific Ring of Fire. Physiographically, they are a distinct section of the larger Pacific Border province, which in turn is part of the larger Pacific Mountain System physiographic division. These Islands are most known for the battles and skirmishes that occurred there during the Aleutian Islands Campaign of World War II. It was one of only two attacks on the United States during that war.

Links Aleutian Islands : Map (The Full Wiki) The Full Wiki Wikipedia article: Map showing all locations mentioned on Wikipedia article: The Aleutian Islands (possibly from Chukchi aliat, " island ") are a chain of more than 300 small volcanic islands forming part of the Aleutian Arc in the Northern Pacific Ocean , occupying an area of 6,821 sq mi (17,666 km²) and extending about westward from the Alaska Peninsula toward the Kamchatka Peninsula . Crossing longitude 180°, they are the westernmost part of the United States (and by one definition the easternmost; see Extreme points of the United States ). Nearly all the archipelago is part of Alaska and usually considered as being in the " Alaskan Bush ", but at the extreme western end the small, geologically-related, and remote Commander Islands are in Russia . The islands, with their 57 volcanoes, are in the northern part of the Pacific Ring of Fire . The Alaska Marine Highway passes through the islands. Physiographically, they are a distinct section of the larger Pacific Border province, which in turn is part of the larger Pacific Mountain System physiographic division.

Geography Aleutians seen from space The islands, known before 1867 as the Catherine Archipelago, comprise five groups (east to west): the Fox island groups (with Buldir Island halfway between Favian and Diana Islands, but part of neither group). They are all located between 52° and 55° N latitude and 172° E and 163° W longitude. The axis of the archipelago near the mainland of Alaska has a southwest trend, but near the 179th meridian its direction changes to the northwest. This change of direction corresponds to a curve in the line of volcanic fissures that have contributed their products to the building of the islands. Such curved chains are repeated about the Pacific Ocean in the Kuril Islands , the Japanese chain, and in the Philippines . All these island arcs are at the edge of the Pacific Plate and experience a lot of seismic activity, but are still habitable; the Aleutians lie between the Pacific and North American tectonic plates . The general elevation is greatest in the eastern islands and least in the western. The island chain is a western continuation of the Aleutian Range on the mainland.

Active Aleutian volcanoes The great majority of the islands bear evident marks of volcanic origin, and there are numerous volcanic cones on the north side of the chain, some of them active; many of the islands, however, are not wholly volcanic, but contain crystalline or sedimentary rocks, and also amber and beds of lignite . The coasts are rocky and surf-worn, and the approaches are exceedingly dangerous, the land rising immediately from the coasts to steep, bold mountains. Makushin Volcano ( ) located on Unalaska Island, is not quite visible from within the town of Unalaska , though the steam rising from its cone is visible on a (rare) clear day. Denizens of Unalaska need only to climb one of the smaller hills in the area, such as Pyramid Peak or Mt. Newhall, to get a good look at the snow-covered cone. The volcanic Bogoslof and Fire Islands , which rose from the sea in 1796 and 1883 respectively, lie about 30 miles (48 km) west of Unalaska Bay. Climate The climate of the islands is oceanic, with moderate and fairly uniform temperatures and heavy rainfall.

Fogs are almost constant. Summer weather is much cooler than Southeast Alaska ( Sitka ), but the winter temperature of the islands and of the Alaska Panhandle is very nearly the same. During the winter time the islands are the centre for the semipermanent low-pressure area called Aleutian low . The mean annual temperature for Unalaska, the most populated island of the group, is about 38 °F (3.4 °C), being about 30 °F (−1.1 °C) in January and about 52 °F (11.1 °C) in August. The highest and lowest temperatures recorded on the islands are 78 °F (26 °C) and 5 °F (−15 °C) respectively. The average annual rainfall is about 80 in (2,030 mm), and Unalaska, with about 250 rainy days per year, is said to be one of the rainiest places within the United States .

Flora Cape Promontory, Cape Lutkes in the Aleutian Islands, Alaska The growing season lasts about 135 days, from early in May till late in September, but agriculture is limited to the raising of a few vegetables. With the exception of some stunted willows , the vast majority of the chain is destitute of native trees. On some of the islands, such as Adak and Amaknak , there are a few coniferous trees growing, remnants of the Russian period . While tall trees grow in many cold climates, Aleutian conifers—some of them estimated to be two hundred years old—rarely reach a height of even ten feet, and many of them are still less than five feet tall. This is because the islands, much like the Falklands and other islands of similar latitudes , experience such strong winds that taller trees are vulnerable to snapping off. Instead of trees, the islands are covered with a luxuriant, dense growth of herbage, including grasses , sedges , and many flowering plants. Economy On the less mountainous islands, the raising of sheep and reindeer was once believed to be practicable. There are Bison on islands near Sand Point.

Sheep raising seems to have died off with the advent of synthetic fibers which lowered the value of wool. During the 1980s, there were some llama being raised on Unalaska . Today, the economy is primarily based upon fishing , and, to a lesser extent, the presence of American military. The only crop is potato . Chickens are raised in barns under protection from cold. Demographics The native people refer to themselves as Unangan, and are now generally known by most non-natives as the " Aleut ". The Aleut language is one of the two main branches of the Eskimo-Aleut language family. This family is not known to be related to any others. In the 2000 census , there was a population of 8,162 on the islands, of whom 4,283 were living in the main settlement of Unalaska . History Prehistory Because of the location of the islands, stretching like a broken bridge from Asia to America, many anthropologists believe they were a route of the first human occupants of the Americas.

The earliest known evidence of human occupation in the Americas is much further south; the early human sites in Alaska have probably been submerged by rising waters during the current interglacial period.People living in the Aleutian Islands developed fine skills in hunting, fishing, and basketry. Hunters made their weapons and watercraft. The baskets are noted for being finely woven with carefully shredded stalks of beach rye. Russian period Explorers, traders and missionaries arrived from Russia beginning in 1741. In 1741 the Russian government sent Vitus Bering , a Dane in the service of Russia, and Aleksei Chirikov , a Russian, in the ships Saint Peter and Saint Paul on a voyage of discovery in the Northern Pacific . After the ships were separated by a storm, Chirikov discovered several eastern islands of the Aleutian group, and Bering discovered several of the western islands, finally being wrecked and losing his life on the island of the Komandorskis ( Commander Islands ) that now bears his name ( Bering Island ).

The survivors of Bering's party reached the Kamchatka Peninsula in a boat constructed from the wreckage of their ship, and reported that the islands were rich in fur-bearing animals. Siberian fur hunters flocked to the Commander Islands and gradually moved eastward across the Aleutian Islands to the mainland. In this manner, Russia gained a foothold on the northwestern coast of North America. The Aleutian Islands consequently belonged to Russia, until that country transferred all its possessions in North America to the United States in 1867. The Russians were ruthless in their expansion, using technology and cruelty to enslave the Aleuts, especially for sea otter hunting. The Russians captured otter pelts from the Aleutian Islands, through the Gulf of Alaska , along the Alaska Panhandle, and south, even to California . Some Aleuts were moved to the Pribilof Islands so that fur seals could be captured there as well. By 1760, the Russian merchant Andrian Tolstykh had made a detailed census in the vicinity of Adak and extended Russian citizenship to the Aleuts.

Despite some attempts to eliminate slavery and reduce cruel treatment in the 1790s, the Shelikhov company depended on the labor of Aleut hunters to collect sea otter pelts. During his third and last voyage, in 1778, Captain James Cook surveyed the eastern portion of the Aleutian archipelago, accurately determined the position of some of the more important islands, and corrected many errors of former navigators. Christian influences Among the first Christian missionaries to arrive in the Aleutian Islands was a party of ten Russian Orthodox monks and priests, who arrived in 1793. Within two years, a monk named Herman was the only survivor of that party. He settled on Spruce Island , and often defended the rights of the Aleuts against the Russian trading companies. He is now known in the Orthodox Church as Saint Herman of Alaska . Another early Christian missionary of the Russian Orthodox Church was Father Veniaminov who arrived in Unalaska in 1824. He was named Bishop Innokentii in 1840 and moved to Sitka . He is now known in the Orthodox Church as Saint Innocent of Alaska . The principal settlements were on Unalaska Island.

The oldest was Iliuliuk (also called Unalaska), settled in 1760-1775, with a customs house and an Orthodox church. U.S. possession After the American purchase of Alaska from Russia in 1867, further development took place. New buildings included a Methodist mission and orphanage, and the headquarters for a considerable fleet of United States revenue cutters which patrolled the sealing grounds of the Pribilof Islands . The first public school in Unalaska opened in 1883. The U.S. Congress extended American citizenship to all Natives (and this law has been held to include the indigenous peoples of Alaska) in 1924. A hospital was built in Unalaska in 1933 by the U.S. Bureau of Indian Affairs . World War II and Kiska were invaded in order to divert American forces away from the main Japanese attack at Midway Atoll . The U.S. Navy, having broken the Japanese naval codes , knew that this was just a diversion, and it did not expend large amounts of effort in defending the islands. A few Americans were taken to Japan as prisoners of war.

Most of the civilian population of the Aleutians were interned by the United States in camps in the Alaska Panhandle . During the Aleutian Islands Campaign , American and Canadian forces invaded Japanese-held Attu and defeated the Japanese, and subsequently regained control of all the islands. The islands were also a stopping point for hundreds of aircraft sent from California to Russia as part of the war effort. Monday, June 3, 2002 was celebrated as Dutch Harbor Remembrance Day. The governor of Alaska ordered state flags lowered to half-staff to honor the 78 soldiers who died during the two-day Japanese air attack in 1942. The Aleutian World War II National Historic Area Visitors Center opened in June 2002. Recent and miscellaneous developments The Alaska Native Claims Settlement Act became law in 1971. In 1977, the Ounalashka Corporation (from Unalaska) declared a dividend . This was the first village corporation to declare and pay a dividend to its shareholders. In 1906 a new volcanic cone rose between the islets of Bogoslof and Grewingk, near Unalaska, followed by another in 1907.

These cones were nearly demolished by an explosive eruption on September 1, 1907. Nuclear Testing on Amchitka from 1965 to 1971 as part of the Vela Uniform program. The final detonation, the Cannikin, was the largest underground nuclear explosion by the United States. See also THE BERING SEA AND ALEUTIAN ISLANDS Map of the Bering Sea and Aleutian Islands THE BERING SEA The Bering Sea is a marginal sea of the Pacific Ocean. It comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelves. The Bering Sea is separated from the Gulf of Alaska by the Alaska Peninsula. It covers over 2,000,000 square kilometres (770,000 sq mi) bordered on the east and northeast by Alaska , on the west by Russia's Far East and Kamchatka Peninsula, on the south by the Alaska Peninsula and the Aleutian Islands and on the far north by the Bering Strait, which connects the Bering Sea to the Arctic Ocean's Chukchi Sea.

Bristol Bay is the portion of the Bering Sea which separates the Alaska Peninsula from mainland Alaska. The Bering Sea is named for Vitus Bering, a Danish navigator in Russian service, who in 1728 was the first European to systematically explore it, sailing from the Pacific Ocean northward to the Arctic Ocean. The Bering Sea ecosystem includes resources within the jurisdiction of the United States and Russia , as well as international waters in the middle of the sea (known as the "Donut Hole"). The interaction between currents, sea ice, and weather makes for a vigorous and productive ecosystem. THE BERING STRAIGHT The Bering Strait (Russian: Берингов пролив, Beringov proliv, Yupik: Imakpik) is a strait 82 kilometres (51 mi; 44 nmi) wide at its narrowest point, between Cape Dezhnev, Chukchi Peninsula, Russia, the easternmost point (169ï¿½ 43' W) of the Asian continent and Cape Prince of Wales, Alaska, USA, the westernmost point (168ï¿½ 05' W) of the North American continent.

Named after Vitus Bering, a Russian explorer born in Denmark , it lies slightly south of the polar circle at approximately 65ï¿½ 40' N latitude, with the present US-Russia east-west boundary, agreed to only by the USA, at 168ï¿½ 58' 37" W. The Strait has been the subject of scientific speculation that humans migrated from Asia to North America across a land bridge known as Beringia when lower ocean levels ï¿½ perhaps a result of glaciers locking up vast amounts of water ï¿½ exposed a wide stretch of the sea floor, both at the present strait and in the shallow sea north and south of it. This view of how paleo-indians entered America has been the dominant one for several decades and continues to be the most accepted one. As of 2014, the Russian coast of the Bering Strait has been a closed military zone since 2012. Through organised trips and the use of special permits, it is possible for foreigners to visit. All arrivals must be through an airport or a cruise port.

Unauthorized travelers who arrive on shore after crossing the strait, even those with visas, may be arrested, imprisoned briefly, fined, deported and banned from future visas. The Bering Strait is approximately 82 kilometres (51 mi; 44 nmi) wide at its narrowest point, with depth varying between 30 metres (98 ft) and 50 metres (160 ft). It connects the Chukchi Sea (part of the Arctic Ocean) to the north with the Bering Sea (part of the Pacific Ocean) to the south. The International Date Line runs equidistant between the Strait's Diomede Islands at a distance of 1.5 km (1 mi), leaving the Russian and American sides usually on different calendar days, with Cape Dezhnev 21 hours ahead of the American side (20 hours during daylight saving time). The Humpback whale is one of the most prolific cetaceans to frequent these rich feeding grounds, also one of the most playful. Broaching is a spectacular treat for visitors. Kulo Luna is shown above as a calf.

BIODIVERSITY The sea supports many endangered whale species including Bowhead Whale, Blue Whale , Fin Whale, Sei Whale, Humpback Whale , Sperm Whale and the rarest in the world, the North Pacific Right Whale . Other marine mammals include walrus, Steller Sea Lion, Northern Fur Seal , Beluga, Orca and polar bear . The Bering Sea is very important to the seabirds of the world. Over 30 species of seabirds and approximately 20 million individuals breed in the Bering Sea region. Seabird species include Tufted Puffins, the endangered Short-tailed Albatross, Spectacled Eider, and Red-legged Kittiwakes. Many of these species are unique to the area, which provides highly productive foraging habitat, particularly along the shelf edge and in other nutrient-rich upwelling regions, such as the Pribilof, Zhemchug, and Pervenets canyons. The Bering Sea is also home to colonies of Crested Auklets, with upwards of a million individuals.

Two Bering Sea species, the Steller's Sea Cow (Hydrodamalis gigas) and Spectacled Cormorant (Phalacrocorax perspicillatus), are extinct because of overexploitation by man. In addition, a small subspecies of Canada goose, the Bering Canada goose (Branta canadensis asiatica) is extinct due to overhunting and introduction of rats to their breeding islands. The Bering Sea supports many species of fish. Some species of fish support large and valuable commercial fisheries. Commercial fish species include 6 species of Pacific Salmon, Alaska Pollock, Red King Crab, Chionoecetes Pacific cod, Pacific halibut, Yellowfin Sole, Pacific ocean perch and sablefish. Fish biodiversity is high, and at least 419 species of fish have been reported from the Bering Sea. The Bering Sea is world renowned for its enormously productive and profitable fisheries, such as King Crab, opilio and tanner crabs, Bristol Bay salmon, pollock and other groundfish. These fisheries rely on the productivity of the Bering Sea via a complicated and little understood food web. The continued existence of these fisheries requires an intact, healthy, and productive ecosystem.

Commercial fishing is big business in the Bering Sea, which is relied upon by the largest seafood companies in the world to produce fish and shellfish. On the U.S. side, commercial fisheries catch approximately $1 billion worth of seafood annually, while Russian Bering Sea fisheries are worth approximately $600 million annually. The Bering Sea also serves as the central location of the Alaskan king crab and Opilio crab seasons, which are chronicled on the Discovery Channel television program Deadliest Catch. Landings from Alaskan waters represents half the U.S. catch of fish and shellfish. THE ALEUTIAN ISLANDS The Aleutian Islands (/əˈl(j)uːʃən/; possibly from Chukchi aliat, "island") are a chain of 14 large volcanic islands and 55 smaller ones belonging to both the United States and Russia.

They form part of the Aleutian Arc in the Northern Pacific Ocean, occupying an area of 6,821 sq mi (17,666 kmï¿½) and extending about 1,200 mi (1,900 km) westward from the Alaska Peninsula toward the Kamchatka Peninsula in Russia, and mark a dividing line between the Bering Sea to the north and the Pacific Ocean to the south. Crossing longitude 180ï¿½, at which point east and west longitude end, the archipelago contains both the westernmost part of the United States by longitude (Amatignak Island) and the easternmost by longitude (Semisopochnoi Island). The westernmost U.S. island in real terms, however, is Attu Island, west of which runs the International Date Line. While nearly all the archipelago is part of Alaska and is usually considered as being in the "Alaskan Bush", at the extreme western end, the small, geologically related Commander Islands belong to Russia. The islands, with their 57 volcanoes , are in the northern part of the Pacific Ring of Fire.

Physiographically, they are a distinct section of the larger Pacific Border province, which in turn is part of the larger Pacific Mountain System physiographic division. * Rat; and * Near. All five are located between 51ï¿½ and 55ï¿½ N latitude and 172ï¿½ E and 163ï¿½ W longitude. The largest islands in the Aleutians are Attu (the furthest from the mainland), and Unalaska, Umnak, and Akun in the Fox Islands. The axis of the archipelago near the mainland of Alaska has a southwest trend, but near 179ï¿½ its direction changes to the northwest. This change of direction corresponds to a curve in the line of volcanic fissures that have contributed their products to the building of the islands. Such curved chains are repeated about the Pacific Ocean in the Kuril Islands, the Japanese chain, and in the Philippines . All these island arcs are at the edge of the Pacific Plate and experience much seismic activity, but are still habitable; the Aleutians lie between the Pacific and North American tectonic plates. The general elevation is greatest in the eastern islands and least in the western.

The island chain is a western continuation of the Aleutian Range on the mainland. The great majority of the islands bear evident marks of volcanic origin, and there are numerous volcanic cones on the north side of the chain, some of them active; many of the islands, however, are not wholly volcanic, but contain crystalline or sedimentary rocks, and also amber and beds of lignite. The coasts are rocky and surf-worn, and the approaches are exceedingly dangerous, the land rising immediately from the coasts to steep, bold mountains. These volcanic islands reach heights of 6,200 feet (1,900 m). Makushin Volcano (5,691 feet (1,735 m)) located on Unalaska Island, is not quite visible from within the town of Unalaska, though the steam rising from its cone is visible on a (rare) clear day. Residents of Unalaska need only to climb one of the smaller hills in the area, such as Pyramid Peak or Mt. Newhall, to get a good look at the snow-covered cone.

The volcanic Bogoslof and Fire Islands, which rose from the sea in 1796 and 1883 respectively, lie about 30 miles (50 km) west of Unalaska Bay. (extract from: Kulo Luna The $Billion Dollar Whale by Jameson Hunter ) The Arctic region is a vast region of icy seas and snow covered lands where the sun does not set in summer, nor rise in winter. This desolate expanse is home to hardy Eskimos, a race of superbly adapted nomadic aboriginal flesh eaters, polar bears and seals. Around the North Pole, the waters are permanent sheet or pack ice. Further south, the ice melts in summer, which melt is gradually creeping north as the earth is warming. In winter Eskimos shelter in igloos, in summer in animal skin tents. They live on a mixture of fish, seals and the occasional whale, when meat is plentiful. Their clothes are fashioned from furs and they are skilled artisans. Further south at the rim of the Bering Sea, the Aleutian Islands are the feeding grounds for the humpback whale, giant rorqual acrobats and accomplished vocalists.

Humpback whales have strange white patch splashes on their unusually large front flippers and body undersides, presumably as camouflage. The flippers are roughly a third of body length and irregular shaped with round knob like projections on their large upper and lower jaws, and long head. Humpbacks are fond of leaping out of the water in a display called broaching, when their deeply notched tail flukes are a distinguishing feature. Humpbacks have widely spaced throat grooves that expand in billows fashion to allow them to intake large volumes of water. They have no teeth, but feed by filling their mouths with water containing zooplankton, krill and fish, then filtering out the water, expelling it through flexible baleen strips made of keratin, a strong fingernail like substance, which hang in closely packed rows, curtain fashion from the upper jaw. The small animals trapped in their mouths by this sieving process are then swallowed. Groups of Humpbacks hunt in teams, swimming in circles around a fish shoal making bait balls in a technique known as bubble net feeding. A dozen or so whales work together to harvest the bonanza of shoals.

This requires a high degree of intelligence, good timing and communication; the water equivalent of pack hunting. The lead whale dives first and locates a shoal, then swims around it in a circle releasing air bubbles to create a theoretical spiral curtain. The other whales join the leader from underneath in a tight formation, singing to confuse the fish. The fish are then panicked to swim ahead reluctant to enter the bubble curtain barrier, so swim upwards, followed by the whales who all surface mouths agape to net a concentrated fish mouthful. Using this method the whales can easily take a ton of fish a day. Humpback whales can vocalise for up to thirty minutes at a time. Each song is complicated and unique when compared to songs from other whales in their group. Clearly, singing is a means of communication. They are the longest most complex sound sequences of any animal, save for the vocalisations performed by humans supported by orchestras in operas. These songs can be heard many miles away and each regional population has its own song, sung only during the breeding season. To sing, the whale vibrates air inside itself, in a chamber of bone, but how they achieve this is a mystery, since they have no vocal chords.

The bone chamber appears to be a natural harmonic wind instrument. The Greek philosopher Aristotle recognised that whales breathed air and bore live young as far back as 310BC. Cetaceans are divided into two suborders: Odontceti (toothed) and Mysticeti (baleen) whales, with two blowholes on top of their heads. There are 12 baleen species divided into 4 families. Humpbacks are rorqual whales belonging to the ï¿½balaenopteridaeï¿½ family. Mothers are protective of calves which they suckle for 10-11 months weaning at about 12 months. The calves reach maturity at around 5 years. They can weigh up to 45 tonnes and grow up to 19 metres in length. Kulo is considerably heavier, a veritable giant weighing nearly 60 tons. Female Humpbacks typically breed every 2-3 years. It was early in the fall and the beginning of the annual migration from the Gulf of Alaska to the Philippines.

One group of North Pacific humpback whales had already started the 3,500 kilometre journey to warmer waters, a grand summer migration, to complete the reproduction cycle; and a very necessary adventure to allow calves to be born in more comfortable surroundings. Migrations are thought to have developed when the food whales fed on moved to cooler waters as changes in continental drifts and ocean currents took place. whales simply followed the food supply as they moved to polar regions, but habitually returned to warmer sheltered waters to provide a suitable environment to give birth. Their migrations often extend to 16 to 20,000 kilometres in total in a year, so this is just one small leg of their journey. The young and mature males were always the first to leave the group, eager to mark their territory. The adult females joined in, as a trickle herd, out to stretch their muscles after many months of gorging in the rich feeding grounds that are the trademark of the northern waters. Many land mammals and birds, make long treks to reach seasonal feeding grounds, but these treks are dwarfed by the vast annual journeys made by whales.

The last to leave, is the giant female named Kulo, shadowing her young female friend called Kana. These two whales had been identified and tagged by SPLASH project volunteers (Structure of Populations, Levels of Abundance and Status of Humpbacks). Their names had been given to them after deciphering of their grunts and singing, by a computer sampler linked to a hydrophone. Kulo and Kana had become great friends despite their disparity in size. Kulo was by far the largest whale in the group and a gentle giant, even bigger than her male counterparts. She is very strong and confident and well respected because she is also clever. She has a temper, which very occasionally snaps; then watch out. Many a male humpback taking liberties had been chased, caught and bruised for their troubles. If a human, sheï¿½d have been a redhead, Maureen Oï¿½Hara. Kana, is the smallest and youngest of the group, so a slow swimmer, but intent on meeting her sisters at the other end of the migration route. The epic exodus normally lasts from 4 to 8 weeks, depending on the rate of swim and currents.

Kulo was in no particular hurry as she set a southerly bearing for the Babuyan Islands, just north of Luzon, in the Philippines. Although of course, she did no know the Islandï¿½s name, nor the compass bearing. She just knew the Island by its taste, warm clear, sheltered waters and the feeling of well being when she reached that location. Humpback whales navigate by sensing Earthï¿½s geomagnetic field. The tissues around their brains contain an iron oxide concentration called magnetite, allowing them to sense gradients. There are many different groups of whales in three populations spread about the globe, each with their own familiar pattern and customs. Some are North Atlantic and others cruise the Southern Hemisphere. Kulo and Kana are from a northern Pacific group, by far the biggest group of whales, making up approximately 60% of the worldï¿½s humpback whale population. Kulo has eaten her fair share of schooling fish and krill and packed it all away in natureï¿½s larder as blubber, which stores and releases energy on demand to sustain these wonderful animals on their travels.

As she swam along she thought of all those long summer days chasing and being chased by the adult males, in a ritual as old as time itself, but none the less enjoyable for that. All the while the sun shone, providing the energy for photosynthesis, the basis of nearly all life on earth. This chemical reaction makes the algae bloom aplenty as they manufacture carbohydrates, which in turn provides food for the next in line in the food chain. Humpback adults can eat up to 2,000 pounds of krill in a single day. Every food chain eventually comes to a halt with the dominant animal it supports, in this case the humpback. Food chains as with any other form of energy conversion are dreadfully inefficient when viewed clinically. When man broke the back of the food chain by growing his own crops, on which to rely, he accidentally improved the efficiency of the supply chain and gave humans a huge advantage over other species. The invention of cooking, further improved the digestive conversion ratio, then man farmed animals intensively, since he had the crops to feed them and control of the environment, to include controlling his meat supply. But that didnï¿½t matter to our friendly whales.

What mattered was when man became master of the oceans and greedy for energy. Whole towns were built up specifically to hunt for whales and the precious oils they could provide. This was before the discovery of petroleum in vast subterranean lakes, fractional distillation and the invention of the motor car. A large whale could be reduced to around 100 barrels of oil at about 10 barrels to the ton, plus other exotic compounds used as perfumes and lubricants, such as ambergris. The oil in the head of the Sperm Whale has such fine lubricating qualities, that only up until recently did NASA use it for their space programme. At first the herds of these giant gray animals must have seemed an inexhaustible bonanza. But just as with the Bison of North America, slowly but steadily the population dwindled, until many species were on the verge of extinction. For this reason laws were introduced banning whaling, to prevent extinction. The International Whaling Commission was established in 1946 to conserve what stocks remained. An indefinite moratorium on all commercial whaling was imposed in 1982.

The Convention of International Trade in Endangered Species of Wild Fauna and Flora, prohibits trade in whale products, formerly used extensively in cosmetics and for ornamental carvings. The measures which are now taken to protect whales, has seen a revival of numbers, but the population is still only about a fifth of the pre-whaling days. Where the people of Iceland, Japan and China traditionally included whale meat in their diet, the whaling ban has hit them hard. Eskimos still hunt whales in limited fashion, but they are not an industrialised nation, thus the impact on whale stocks is negligible. Very occasionally, Iceland has taken a few whales to a strict quota, but Japan operates large mechanised whaling ships, claiming that whales taken are for scientific research, which many authorities allege, due to the numbers, is in defiance of international treaties. For this reason fisheries protection agencies shadow such ships, to ensure there is no refueling at sea, which is prohibited to in some measure limit hunting locations. Purpose designed whaling ships are more readily detectable by their size and shadowed by fisheries authorities and animal rights protection groups.

Smaller privately owned fishing vessels are not so easy to keep track of, since they may be general purpose boats, converted from trawlers or other working ships. These opportunistic brigands are more dangerous to Kulo and her group, as they mingle with other marine transport. Advances in marine electronics, such as echo location fish finders and other sonar devices, makes the job of trawler captains that much easier. The problem though for modern whalers, is oddly enough, not one that the Captain Ahabs of yesteryear faced. It is the price of fuel and range limitations of the modern diesel engine powered boat. Kulo is not thinking of any of these issues which affect the survival of her species. She is happy to be watching her friend Kana stretching her flippers, rising and leaping from the sea and falling back amid a wave of silver froth and slapping her tail flukes, which is a sign of whale happiness. Kulo is thinking of meeting up with her mate Buka, himself a bigger than normal male humpback, who courted her for most of the winter, until finally they had a meeting of minds.

Aleutian Islands - Wikipedia, the free encyclopedia Aleutian Islands Jump to: navigation , search This article needs additional citations for verification . Please help improve this article by adding reliable references . Unsourced material may be challenged and removed . (October 2008) Aleutian Islands 6,821 sq mi (17,666 km2) Length Aleut The Aleutian Islands (possibly from Chukchi aliat, " island ") are a chain of more than 300 small volcanic islands forming part of the Aleutian Arc in the Northern Pacific Ocean , occupying an area of 6,821 sq mi (17,666 km²) and extending about 1,200 mi (1,931 km) westward from the Alaska Peninsula toward the Kamchatka Peninsula . Crossing longitude 180° , they are the westernmost part of the United States (and by one definition the easternmost; see Extreme points of the United States ).

Nearly all the archipelago is part of Alaska and usually considered as being in the " Alaskan Bush ", but at the extreme western end the small, geologically-related, and remote Commander Islands are in Russia . The islands, with their 57 volcanoes, are in the northern part of the Pacific Ring of Fire . The Alaska Marine Highway passes through the islands. Physiographically, they are a distinct section of the larger Pacific Border province, which in turn is part of the larger Pacific Mountain System physiographic division. Contents Unalaska Island in the Aleutian Islands. Active Aleutian volcanoes. The islands, known before 1867 as the Catherine Archipelago, comprise five groups (east to west): the Fox , Islands of Four Mountains , Andreanof , Rat , and Near island groups (with Buldir Island halfway between Favian and Diana Islands, but part of neither group). They are all located between 52° and 55°N latitude and 172°E and 163°W longitude . The axis of the archipelago near the mainland of Alaska has a southwest trend, but near the 179th meridian east its direction changes to the northwest.

This change of direction corresponds to a curve in the line of volcanic fissures that have contributed their products to the building of the islands. Such curved chains are repeated about the Pacific Ocean in the Kuril Islands , the Japanese chain, and in the Philippines . All these island arcs are at the edge of the Pacific Plate and experience much seismic activity, but are still habitable; the Aleutians lie between the Pacific and North American tectonic plates . The general elevation is greatest in the eastern islands and least in the western. The island chain is a western continuation of the Aleutian Range on the mainland. The great majority of the islands bear evident marks of volcanic origin, and there are numerous volcanic cones on the north side of the chain, some of them active; many of the islands, however, are not wholly volcanic, but contain crystalline or sedimentary rocks, and also amber and beds of lignite . The coasts are rocky and surf-worn, and the approaches are exceedingly dangerous, the land rising immediately from the coasts to steep, bold mountains.

Makushin Volcano (5,691 feet (1,735 m)) located on Unalaska Island, is not quite visible from within the town of Unalaska , though the steam rising from its cone is visible on a (rare) clear day. Denizens of Unalaska need only to climb one of the smaller hills in the area, such as Pyramid Peak or Mt. Newhall, to get a good look at the snow-covered cone. The volcanic Bogoslof and Fire Islands , which rose from the sea in 1796 and 1883 respectively, lie about 30 miles (48 km) west of Unalaska Bay. The Aleutians seen from space Image of the islands taken by the STS-56 crew. These cloud formations were seen over the western Aleutian Islands. Aster image of the islands. [ edit ] Climate The climate of the islands is oceanic, with moderate and fairly uniform temperatures and heavy rainfall. Fogs are almost constant. Summer weather is much cooler than Southeast Alaska ( Sitka ), but the winter temperature of the islands and of the Alaska Panhandle is very nearly the same.

During the winter time the islands are the center for the semipermanent low-pressure area called Aleutian low . The mean annual temperature for Unalaska, the most populated island of the group, is about 38°F (3.4°C), being about 30°F (−1.1°C) in January and about 52 °F (11.1 °C) in August. The highest and lowest temperatures recorded on the islands are 78°F (26°C) and 5°F (−15°C) respectively. The average annual rainfall is about 80 in (2,030 mm), and Unalaska, with about 250 rainy days per year, is said to be one of the rainiest places within the United States . Cape Promontory, Cape Lutkes on Unimak Island in the Aleutian Islands, Alaska. The growing season lasts about 135 days, from early in May till late in September, but agriculture is limited to the raising of a few vegetables. With the exception of some stunted willows , the vast majority of the chain is destitute of native trees.

On some of the islands, such as Adak and Amaknak , there are a few coniferous trees growing, remnants of the Russian period . While tall trees grow in many cold climates, Aleutian conifers—some of them estimated to be two hundred years old—rarely reach a height of even ten feet, and many of them are still less than five feet tall. This is because the islands, much like the Falklands and other islands of similar latitudes , experience such strong winds that taller trees are vulnerable to snapping off. Instead of trees, the islands are covered with a luxuriant, dense growth of herbage, including grasses , sedges , and many flowering plants. [ edit ] Economy On the less mountainous islands, the raising of sheep and reindeer was once believed to be practicable. There are Bison on islands near Sand Point. Sheep raising seems to have died off with the advent of synthetic fibers which lowered the value of wool. During the 1980s, there were some llama being raised on Unalaska . Today, the economy is primarily based upon fishing , and, to a lesser extent, the presence of American military. The only crop is potato .

Chickens are raised in barns under protection from cold. [ edit ] Demographics The native people refer to themselves as Unangan, and are now generally known by most non-natives as the " Aleut ". The Aleut language is one of the two main branches of the Eskimo-Aleut language family. This family is not known to be related to any others. In the 2000 census , there was a population of 8,162 on the islands, of whom 4,283 were living in the main settlement of Unalaska . [ edit ] Prehistory Because of the location of the islands, stretching like a broken bridge from Asia to America, many anthropologists believe they were a route of the first human occupants of the Americas. The earliest known evidence of human occupation in the Americas is much farther south; the early human sites in Alaska have probably been submerged by rising waters during the current interglacial period. People living in the Aleutian Islands developed fine skills in hunting, fishing, and basketry. Hunters made their weapons and watercraft. The baskets are noted for being finely woven with carefully shredded stalks of beach rye.

[ edit ] Russian period Explorers, traders and missionaries arrived from Russia beginning in 1741. In 1741 the Russian government sent Vitus Bering , a Dane in the service of Russia, and Aleksei Chirikov , a Russian, in the ships Saint Peter and Saint Paul on a voyage of discovery in the Northern Pacific . After the ships were separated by a storm, Chirikov discovered several eastern islands of the Aleutian group, and Bering discovered several of the western islands, finally being wrecked and losing his life on the island of the Komandorskis ( Commander Islands ) that now bears his name ( Bering Island ). The survivors of Bering's party reached the Kamchatka Peninsula in a boat constructed from the wreckage of their ship, and reported that the islands were rich in fur-bearing animals. Siberian fur hunters flocked to the Commander Islands and gradually moved eastward across the Aleutian Islands to the mainland. In this manner, Russia gained a foothold on the northwestern coast of North America. The Aleutian Islands consequently belonged to Russia, until that country transferred all its possessions in North America to the United States in 1867.

During the consolidation of the Russian-American Company there was sporadic conflict with the native population (frequently disastrous to the poorly-armed and vastly-outnumbered Russians). The colonies soon entered a relatively stable state based on cooperation, intermarriage, and official policies that provided social status, education, and professional training to children of mixed Aleut-Russian birth. [1] Within a generation or two the day-to-day administration of the Russian-American colonies was largely in the hands of native-born Alaskans. Reversing the usual trend in colonization where indigenous technologies are replaced, the Russians adopted the Aleut kayak, or baidarka , sea otter hunting techniques, and the working of native copper deposits. The Russians instituted public education, preservation of the Aleut language through transliteration of religious and other texts into Aleut via an adaptation of the Cyrillic alphabet, vaccination of the native population against smallpox , and science-based sea mammal conservation policies that were far ahead of their time. [2] By 1760, the Russian merchant Andrian Tolstykh had made a detailed census in the vicinity of Adak and extended Russian citizenship to the Aleuts.

During his third and last voyage, in 1778, Captain James Cook surveyed the eastern portion of the Aleutian archipelago, accurately determined the position of some of the more important islands, and corrected many errors of former navigators. [ edit ] Christian influences Among the first Christian missionaries to arrive in the Aleutian Islands was a party of ten Russian Orthodox monks and priests, who arrived in 1793. Within two years, a monk named Herman was the only survivor of that party. He settled on Spruce Island , near Kodiak Island , and often defended the rights of the Aleuts against the Russian trading companies. He is now known in the Orthodox Church as Saint Herman of Alaska . Another early Christian missionary of the Russian Orthodox Church was Father Veniaminov who arrived in Unalaska in 1824. He was named Bishop Innokentii in 1840 and moved to Sitka . He is now known in the Orthodox Church as Saint Innocent of Alaska . The principal settlements were on Unalaska Island. The oldest was Iliuliuk (also called Unalaska), settled in 1760-1775, with a customs house and an Orthodox church.

[ edit ] U.S. possession After the American purchase of Alaska from Russia in 1867, further development took place. New buildings included a Methodist mission and orphanage, and the headquarters for a considerable fleet of United States revenue cutters which patrolled the sealing grounds of the Pribilof Islands . The first public school in Unalaska opened in 1883. The U.S. Congress extended American citizenship to all Natives (and this law has been held to include the indigenous peoples of Alaska) in 1924. A hospital was built in Unalaska in 1933 by the U.S. Bureau of Indian Affairs . [ edit ] World War II Main article: Aleutian Islands Campaign During World War II , small parts of the Aleutian islands were occupied by Japanese forces, when Attu and Kiska were invaded in order to divert American forces away from the main Japanese attack at Midway Atoll . The U.S. Navy, having broken the Japanese naval codes , knew that this was just a diversion, and it did not expend large amounts of effort in defending the islands. A few Americans were taken to Japan as prisoners of war.

Most of the civilian population of the Aleutians were interned by the United States in camps in the Alaska Panhandle . During the Aleutian Islands Campaign , American and Canadian forces invaded Japanese-held Attu and defeated the Japanese, and subsequently regained control of all the islands. The islands were also a stopping point for hundreds of aircraft sent from California to Russia as part of the war effort.[ dubious – discuss ] Monday, June 3, 2002 was celebrated as Dutch Harbor Remembrance Day. The governor of Alaska ordered state flags lowered to half-staff to honor the 78 soldiers who died during the two-day Japanese air attack in 1942. The Aleutian World War II National Historic Area Visitors Center opened in June 2002. [ edit ] Recent and miscellaneous developments The Alaska Native Claims Settlement Act became law in 1971. In 1977, the Ounalashka Corporation (from Unalaska) declared a dividend . This was the first village corporation to declare and pay a dividend to its shareholders.

In 1906 a new volcanic cone rose between the islets of Bogoslof and Grewingk, near Unalaska, followed by another in 1907. These cones were nearly demolished by an explosive eruption on September 1, 1907. [ edit ] Nuclear Testing on Amchitka ^ Wikimedia Commons has media related to: Aleutian Islands This article incorporates text from a publication now in the public domain : Chisholm, Hugh, ed (1911). Encyclopædia Britannica (Eleventh ed.). Cambridge University Press. Total area of 6,821 sq mi (17,670 km2)from Encyclopædia Britannica Online [ edit ] Further reading Gibson, Daniel D., and G. Vernon Byrd. Birds of the Aleutian Islands, Alaska. Cambridge, Mass: Nuttall Ornthological Club, 2007. ISBN 9780943610733 Ivanov, Viacheslav Vsevolodovich.

The Russian Orthodox Church of Alaska and the Aleutian Islands and Its Relation to Native American Traditions—An Attempt at a Multicultural Society, 1794-1912. Washington, DC: Library of Congress, 1997. ISBN 0160487811 Jochelson, Waldemar. Archaeological Investigations in the Aleutian Islands. Washington: Carnegie Institution of Washington, 1925. Hotspots A weekly feature provided by scientists at the Hawaiian Volcano Observatory. Hotspots Many of the islands that dot the center of the Pacific Ocean are made up of active, dormant, or extinct volcanoes, whose geologic histories are characteristic of "hot spot" volcanism. The active volcanism is limited to a localized region (or "spot") of the volcanic chain. Hot-spot island chains include the Hawaiian, Marquesas, Society, Pitcairn, Samoan, and Galapagos archipelagos. Volcanoes are also common around the edge of the Pacific Ocean. Examples include the Cascade volcanoes (e.g., Mt. St. Helens), the Aleutians, the volcanoes in Japan (e.g., Mt.

Fuji), the volcanoes of the Philippines (e.g., Mt. Pinatubo), and many others. These volcanoes have earned the Pacific rim the nickname "the Pacific ring of fire". As the name "ring" implies, these volcanic islands are simultaneously active along a line, whereas hot spot volcanism is active only at small "spots." The Pacific rim volcanoes are related to plate boundary processes. The surface of the Earth is made up of about 14 rigid plates, which move relative to each other like boards floating on a pond. Where two plates collide, one plate usually sinks beneath the other deep into the mantle of the Earth. The sinking plate melts to form magma, which rises and forms volcanoes on the overriding plate. This process forms the ring of volcanoes around most of the Pacific Ocean. Where two plates move apart, magma rises and fills in the space. This kind of volcanism occurs deep on the ocean floor. Hot spot volcanoes are special because they can be found both within plates (e.g., Hawaii, Marquesas, and Society islands) and along or near plate boundaries (e.g., Galapagos, Iceland, and Azores islands). This is a map of the earth.

The thick dashed line shows the ridge formed by the Hawaiian hot spot during the last 80 million years. The arrows show the direction and rate of motion of selected plates relative to the hot spots. The plate boundaries are shown by the lines of medium weight, and the "Pacific ring of fire" plate boundaries by heavier lines. The dots mark the youngest islands of some hot spot island chains. Can you name the island groups? The answers can be found at the end of this "Volcano Watch" column. The basic characteristics of hot spot volcanism can be observed using the best scientific tool there is--your eyes! Think about the different Hawaiian islands you have visited. Which one appeared to be the youngest? (The Big Island appears to be the youngest because Kilauea is erupting now and Mauna Loa last erupted in 1984.) Which island is the oldest? (This is a trick question because there are many ways to answer it. Of the islands we can visit, Kauai has the deepest eroded valleys and the most coral reefs, which are indicative of age in the process of island formation and degradation.

The oldest rocks outcropping on Kauai are about 5 million years old--older than the oldest hominid fossils in Africa! The extinct volcano underlying the coral atoll of Midway is 26 million years old. If you could remove all of the water in the Pacific Ocean, you would find that the Hawaiian islands are peaks on a 10,000-foot-high ridge that extends 2,100 miles west-northwest from Hawaii, and then bends northward and extends for another 1,400 miles. The "elbow" in the ridge is about 43 million years old. The northernmost end is about 80 million years old and was formed during the time of the dinosaurs.) The Society Islands follow the same pattern as Hawaii, with the youngest volcano at the southeast end of the island group and the oldest volcano at the northwest end. These observations led to the idea that deep within the earth, well below the "plate traffic," are some sources of magma, called "hot spots", that are fixed relative to each other. Volcanoes form on the plate above the hot spot.

As the plate moves over the hot spot, new volcanoes form, and the old ones, which no longer overlie the hot spot, become extinct. In Hawaii, the hot spot is currently under the active volcanoes of Mauna Loa, Kilauea, and Loihi, a submarine volcano southeast of the Big Island. From the geometry of the islands and submarine ridges on the Pacific Plate, we know that the Pacific Plate has been moving west-northwest for the last 43 million years. The Pacific Plate moved directly northward from about 43 to 80 million years ago. Given the distances and times mentioned in this article, what is the average speed of the Pacific Plate relative to the Hawaii hot spot during the two time intervals? A hot spot volcano making news recently is Fogo in the Cape Verde Islands off of the west coast of Africa. Fogo is a volcanic island that began erupting last week after lying dormant since 1951. One of our HVO scientists is part of the international team assessing the volcanic hazards of Fogo.

The age relations in the Cape Verde Islands are somewhat confusing, but a basic observation is that Fogo and the other westernmost Cape Verde islands have active or dormant volcanoes. The easternmost islands are nearly flat and their volcanoes are extinct. Which direction is the African Plate moving relative to the Cape Verde hot spot? Now when you travel around Polynesia and other hot spot islands or just travel with a map and your imagination, you can observe the degree of erosion, reef growth, and the recency of volcanic activity and estimate which way the plates are moving relative to the hot spots. Note, this doesn't work well for Samoa, perhaps because the islands are near a place where the plates are coming together. Answers: For the last 43 million years the Pacific Plate has been moving an average of 49 miles per million year (or 3 inches per year) to the west-northwest, relative to the Hawaiian hot spot. From 43 to 80 million years ago, the Pacific Plate moved an average of 38 miles per million year (or 2.4 inches per year) to the north, relative to the Hawaiian hot spot. The African Plate moves roughly eastward relative to the Cape Verde hot spot.

Geography quiz: A, Marquesas; B, Society; C, Samoa; D, Eastern Caroline; E, Pitcairn; F, Guadalupe; G, Galapagos; H, Easter; I, Juan Fernandez; J, Iceland; K, Ascension; L, Madeira; M, Canary; N, Azores; O, Cape Verde; P, Fernando de Noronha; Q, Lord Howe; R, Martin Vaz; S, St. Helena; T, Tristan da Cunha; U, Reunion; V, Comores; W, Bouvet; and X, Kerguelen. How many do you know? The URL of this page is Alaska’s Aleutian Islands (Volcano Week 6) — Google Sightseeing Alaska’s Aleutian Islands (Volcano Week 6) Thursday, 25th August 2011 by Ian Brown The Aleutian Islands are the northern boundary of the Pacific Ocean’s ‘ring of fire’. Starting just off the Alaska Peninsula, an arc of more than 300 volcanic islands stretches for almost 2,000km across the Pacific.

While the majority of the islands are part of the state of Alaska, a few of the westernmost islands are Russian territory 1 . While the Aleutian arc continues on mainland Alaska, we’ll focus on a few of the more prominent volcanic islands and other points of note. The islands are generally clustered into five groups – Fox, Islands of Four Mountains, Andreanof, Rat and Near. The Fox group is closest to the Alaskan mainland. It includes Unimak which happens to be the largest island in the chain, and has the tallest volcano – Mount Shishaldin – as well as several other volcanic features. Mount Shishaldin reaches almost 2,900m and is a perfect example of the classic cone-shaped volcano. There appear to be some colour-matching issues with the satellite image, but does zooming in as far as possible really reveal glowing lava at the centre of the cone? This volcano last erupted in 1999, and it is still very seismically active. The Western end of Unimak island has a pair of volcanoes – Pogromni and Westdahl . In the centre of the island is Fisher Caldera , a volcanic zone with numerous small cones and a vivid blue lake.

At the eastern end of the island there is a small village called False Pass. It has less than a 100 residents, and is not visible on the low resolution image of the area. The islands are named for the Aleuts – the indigenous population of the islands and surrounding region. While at one time they may have numbered around 25,000, outside influences have reduced the population to approximately 2,000. The Aleut language, with 3 dialects, is thought to be dying out. Still within the Fox Islands group, Unalaska is another large island, with Makushin volcano dominating the northern coast. With frequent eruptions recorded in the 18th, 19th and 20th centuries, and regular earthquakes detected, it’s likely only a matter of time before Makushin erupts again. To the east of the volcano the island of Unalaska is connected by bridge to the small island of Amaknak and the town which shares the larger island’s name. Tere is also the port of Dutch Harbor which has become well-known for its crab-fishing fleet featured in the TV show Deadliest Catch .

The next group to the west is called Islands of Four Mountains , though there are actually eight islands in the cluster. Many of them are simple volcanic cones with no other land area. The satellite coverage of the area is patchy, with some, like Mount Cleveland , being split between high- and low-resolution images. Thankfully the lovely shadow of the peak of the cone is on the high-res side!

Question: Which chain of volcanic islands is the westernmost part of the USA and is in the northern end of the Pacific 'Ring of Fire'?
Answer: ALEUTIAN ISLANDS