auto-update week 48

oceans/oo.json

@@ -38,7 +38,30 @@
       }
     },
     "Major ocean currents": {
-      "text": "<p>The cold, clockwise-flowing Antarctic Circumpolar Current (West Wind Drift; 21,000 km long) moves perpetually eastward around the continent and is the world's largest and strongest ocean current, transporting 130 million cubic meters of water per second - 100 times the flow of all the world's rivers; it is also the only current that flows all the way around the planet and connects the Atlantic, Pacific, and Indian Oceans; the cold Antarctic Coastal Current (East Wind Drift) is the southernmost current in the world, flowing westward and parallel to the Antarctic coastline</p>"
+      "text": "<p>the cold, clockwise-flowing Antarctic Circumpolar Current (West Wind Drift; 21,000 km long) moves perpetually eastward around the continent and is the world's largest and strongest ocean current, transporting 130 million cubic meters of water per second - 100 times the flow of all the world's rivers; it is also the only current that flows all the way around the planet and connects the Atlantic, Pacific, and Indian Oceans; the cold Antarctic Coastal Current (East Wind Drift) is the southernmost current in the world, flowing westward and parallel to the Antarctic coastline</p>"
+    },
+    "Bathymetry": {
+      "continental shelf": {
+        "text": "The <em>continental shelf </em>(see Figure 1), a rather flat area of the sea floor adjacent to the coast that gradually slopes down from the shore to water depths of about 200 m (660 ft). Dimensions can vary: they may be narrow or nearly nonexistent in some places or extend for hundreds of miles in others. The waters along the continental shelf are usually productive in both plant and animal life, both from sunlight and nutrients from ocean upwelling and terrestrial runoff. Compared to the <em>continental shelf</em> found in other oceans, in Antarctica the continental shelf is narrower and much deeper. In addition, the <em>continental shelf</em> has been deeply scoured by glacial action. The following are examples of features found on the <em>continental shelf</em> of the Southern Ocean (see Figure 2).<br>Astrid Ridge (see also Figure 4)<br>Belgrano Bank<br>Gunnerus Ridge (see also Figure 4)<br>Hayes Bank<br>Iselin Bank"
+      },
+      "continental slope": {
+        "text": "The <em>continental slope</em> (see Figure 1) is where the ocean bottom drops off more rapidly until it meets the deep-sea floor (abyssal plain) at about 3,200 m (10,500 ft) water depth. The deep waters of the continental slope are characterized by cold temperatures, low light conditions, and very high pressures. Sunlight does not penetrate to these depths, having been absorbed or reflected in the water above. The <em>continental slope</em> can be indented by submarine canyons, often associated with the outflow of major rivers. In the case of Antarctica, the <em>continental slope</em> has been scoured by glacial action cutting troughs and canyons down the slope. Another feature of the continental slope are alluvial fans or cones of sediments carried downstream to the ocean by major rivers and deposited down the slope. The following are examples of features found on the <em>continental slope</em> of the Southern Ocean (see Figure 2).<br>Amery Basin (see also Figure 4)<br>Filchner Trough<br>Hillary Canyon<br>Pobeda Canyon (Figure 3)"
+      },
+      "abyssal plains": {
+        "text": "The <em>abyssal plains </em>(see Figure 1), at depths of over 3,000 m (10,000 ft) and covering 70% of the ocean floor, are the largest habitat on earth. Sunlight does not penetrate to the sea floor, making these deep, dark ecosystems less productive than those along the continental shelf. Despite their name, these “plains” are not uniformly flat; they are interrupted by features like hills, valleys, and seamounts. The following are examples of features found on the <em>abyssal plains</em> of the Southern Ocean (see Figures 2, 3, and 4).<br>Amundsen (Abyssal) Plain<br>Enderby (Abyssal) Plain<br>South Indian/Australian-Antarctic Basin<br>Southeast Pacific/Bellinghausen Basin<br>Weddell (Abyssal) Plain"
+      },
+      "mid-ocean ridge": {
+        "text": "The <em>mid-ocean ridge </em>(see Figure 1), rising up from the abyssal plain, is an underwater mountain range, over 64,000 km (40,000 mi) long, rising to an average depth of 2,400 m (8,000 ft). <em>Mid-ocean ridges</em> form at divergent plate boundaries where two tectonic plates are moving apart and new crust is created by magma pushing up from the mantle. Tracing their way around the global ocean, this system of underwater volcanoes forms the longest mountain range on Earth. Fracture Zones are linear transform faults that develop perpendicular to the line of the mid-ocean ridge which can offset the ridge line and divide it into segments. The following are examples of <em>mid-ocean ridges</em> found on the floor of the Southern Ocean (see Figure 2).<br>Pacific-Antarctic Ridge (see also Figure 3)"
+      },
+      "seamounts": {
+        "text": "<em>Seamounts</em> (see Figure 1) are submarine mountains at least 1,000 m (3,300 ft) high formed from individual volcanoes on the ocean floor. They are distinct from the plate-boundary volcanic system of the mid-ocean ridges, because <em>seamounts</em> tend to be circular or conical. A circular collapse caldera is often centered at the summit, evidence of a magma chamber within the volcano. Flat topped <em>seamounts</em> are known as <em>guyots</em>. Long chains of <em>seamounts</em> are often fed by \"hot spots\" in the deep mantle. These hot spots are associated with stationary plumes of molten rock rising from deep within the Earth's mantle. These hot spot plumes melt through the overlying tectonic plate as it moves and supplies magma to the active volcanic island at the end of the chain of volcanic islands and <em>seamounts</em>. The following are examples of <em>seamounts</em> found on the floor of the Southern Ocean (see Figure 2).<br>Akopov Seamounts (Figure 3)<br>De Gerlache Seamounts (see also Figure 3, 4)<br>Endurance Ridge (Figure 4)<br>Marie Byrd Seamount (see also Figure 3)<br>Maud Rise (see also Figure 4)<br>Scott Seamounts (see also Figure 3)"
+      },
+      "ocean trenches": {
+        "text": "<em>Ocean trenches</em> (see Figure 1) are the deepest parts of the ocean floor and are created by the process of subduction. Trenches form along convergent boundaries where tectonic plates are moving toward each other, and one plate sinks (is subducted) under another. The location where the sinking of a plate occurs is called a subduction zone. Subduction can occur when oceanic crust collides with and sinks under (subducts) continental crust resulting in volcanic, seismic, and mountain-building processes. Subduction can also occur in the convergence of two oceanic plates where one will sink under the other and in the process create a deep ocean trench. Subduction processes in oceanic-oceanic plate convergence also result in the formation of volcanoes. Over millions of years, the erupted lava and volcanic debris pile up on the ocean floor until a submarine volcano rises above sea level to form a volcanic island. Such volcanoes are typically strung out in chains called island arcs. As the name implies, volcanic island arcs, which closely parallel the trenches, are generally curved. The following are examples of <em>ocean trenches</em> found on the floor of the Southern Ocean (see Figure 2).<br>South Sandwich Trench (also see Figure 4); note - the deepest location in the Southern Ocean"
+      },
+      "atolls": {
+        "text": "note - due to the extremely cold water there are no atolls in the Southern Ocean"
+      }
     },
     "Elevation": {
       "highest point": {

oceans/xo.json

@@ -38,7 +38,7 @@
       }
     },
     "Major ocean currents": {
-      "text": "The counterclockwise Indian Ocean Gyre comprised of the southward flowing warm Agulhas and East Madagascar Currents in the west, the eastward flowing South Indian Current in the south, the northward flowing cold West Australian Current in the east, and the westward flowing South Equatorial Current in the north; a distinctive annual reversal of surface currents occurs in the northern Indian Ocean; low atmospheric pressure over southwest Asia from hot, rising, summer air results in the southwest monsoon and southwest-to-northeast winds and clockwise currents, while high pressure over northern Asia from cold, falling, winter air results in the northeast monsoon and northeast-to-southwest winds and counterclockwise currents"
+      "text": "the counterclockwise Indian Ocean Gyre comprised of the southward flowing warm Agulhas and East Madagascar Currents in the west, the eastward flowing South Indian Current in the south, the northward flowing cold West Australian Current in the east, and the westward flowing South Equatorial Current in the north; a distinctive annual reversal of surface currents occurs in the northern Indian Ocean; low atmospheric pressure over southwest Asia from hot, rising, summer air results in the southwest monsoon and southwest-to-northeast winds and clockwise currents, while high pressure over northern Asia from cold, falling, winter air results in the northeast monsoon and northeast-to-southwest winds and counterclockwise currents"
     },
     "Bathymetry": {
       "continental shelf": {

oceans/xq.json

@@ -38,7 +38,30 @@
       }
     },
     "Major ocean currents": {
-      "text": "<p>Two major, slow-moving, wind-driven currents (drift streams) dominate: a clockwise drift pattern in the Beaufort Gyre in the western part of the Arctic Ocean and a nearly straight line Transpolar Drift Stream that moves eastward across the ocean from the New Siberian Islands (Russia) to the Fram Strait (between Greenland and Svalbard); sea ice that lies close to the center of the gyre can complete a 360 degree circle in about 2 years, while ice on the gyre periphery will complete the same circle in about 7-8 years; sea ice in the Transpolar Drift crosses the ocean in about 3 years</p>"
+      "text": "<p>two major, slow-moving, wind-driven currents (drift streams) dominate: a clockwise drift pattern in the Beaufort Gyre in the western part of the Arctic Ocean and a nearly straight line Transpolar Drift Stream that moves eastward across the ocean from the New Siberian Islands (Russia) to the Fram Strait (between Greenland and Svalbard); sea ice that lies close to the center of the gyre can complete a 360 degree circle in about 2 years, while ice on the gyre periphery will complete the same circle in about 7-8 years; sea ice in the Transpolar Drift crosses the ocean in about 3 years</p>"
+    },
+    "Bathymetry": {
+      "continental shelf": {
+        "text": "The <em>continental shelf </em>(see Figure 1), a rather flat area of the sea floor adjacent to the coast that gradually slopes down from the shore to water depths of about 200 m (660 ft). Dimensions can vary: they may be narrow or nearly nonexistent in some places or extend for hundreds of miles in others. The waters along the continental shelf are usually productive in both plant and animal life, both from sunlight and nutrients from ocean upwelling and terrestrial runoff. More than one quarter of the Arctic sea floor is <em>continental shelf</em>. The Eurasian shelf is very wide extending out 1,500 km (930 mi) and is the largest <em>continental shelf</em> in the World. The following are examples of features found on the <em>continental shelf</em> of the Arctic Ocean (see Figure 2).<br>Barents Shelf<br>Beaufort Shelf<br>Davis Sill<br>Chukchi Shelf<br>East Siberian Shelf<br>Kara Shelf<br>Laptev Shelf<br>Lincoln Shelf"
+      },
+      "continental slope": {
+        "text": "The <em>continental slope</em> (see Figure 1) is where the ocean bottom drops off more rapidly until it meets the deep-sea floor (abyssal plain) at about 3,200 m (10,500 ft) water depth. The deep waters of the continental slope are characterized by cold temperatures, low light conditions, and very high pressures. Sunlight does not penetrate to these depths, having been absorbed or reflected in the water above. The <em>continental slope</em> can be indented by submarine canyons, often associated with the outflow of major rivers. Another feature of the continental slope are alluvial fans or cones of sediments carried downstream to the ocean by major rivers and deposited down the slope. The following are examples of features found on the <em>continental slope</em> of the Arctic Ocean (see Figure 2).<br>Litke Trough<br>Novaya Zemlya Trough<br>Svyataya Anna Trough (Saint Anna Trough)<br>Voronin Trough"
+      },
+      "abyssal plains": {
+        "text": "The <em>abyssal plains </em>(see Figure 1), at depths of over 3,000 m (10,000 ft) and covering 70% of the ocean floor, are the largest habitat on earth. Sunlight does not penetrate to the sea floor, making these deep, dark ecosystems less productive than those along the continental shelf. Despite their name, these “plains” are not uniformly flat; they are interrupted by features like hills, valleys, and seamounts. The following are examples of features found on the <em>abyssal plains</em> of the Arctic Ocean (see Figure 2).<br>Baffin Basin<br>Canada Basin<br>Fram/Amundsen Basin<br>Greenland Abyssal Plain<br>Iceland Basin<br>Makarov Basin<br>Molloy Deep; note - deepest point in the Arctic Ocean<br>Nansen Basin<br>Norwegian Basin"
+      },
+      "mid-ocean ridge": {
+        "text": "The <em>mid-ocean ridge </em>(see Figure 1), rising up from the abyssal plain, is an underwater mountain range, over 64,000 km (40,000 mi) long, rising to an average depth of 2,400 m (8,000 ft). <em>Mid-ocean ridges</em> form at divergent plate boundaries where two tectonic plates are moving apart and new crust is created by magma pushing up from the mantle. Tracing their way around the global ocean, this system of underwater volcanoes forms the longest mountain range on Earth. Fracture Zones are linear transform faults that develop perpendicular to the line of the mid-ocean ridge which can offset the ridge line and divide it into segments. The following are examples of <em>mid-ocean ridges</em> found on the floor of the Arctic Ocean (see Figure 2).<br>Gakkel Ridge<br>Mohns Ridge"
+      },
+      "seamounts": {
+        "text": "<em>Seamounts</em> (see Figure 1) are submarine mountains at least 1,000 m (3,300 ft) high formed from individual volcanoes on the ocean floor. They are distinct from the plate-boundary volcanic system of the mid-ocean ridges, because <em>seamounts</em> tend to be circular or conical. A circular collapse caldera is often centered at the summit, evidence of a magma chamber within the volcano. Flat topped <em>seamounts</em> are known as <em>guyots</em>. Long chains of <em>seamounts</em> are often fed by \"hot spots\" in the deep mantle. These hot spots are associated with stationary plumes of molten rock rising from deep within the Earth's mantle. These hot spot plumes melt through the overlying tectonic plate as it moves and supplies magma to the active volcanic island at the end of the chain of volcanic islands and <em>seamounts</em>. The following are examples of <em>seamounts</em> found on the floor of the Arctic Ocean (see Figure 2).<br>Alpha Ridge<br>Chukchi Plateau<br>Iceland Plateau<br>Lomonosov Ridge<br>Mendeleev Rise<br>Voring Plateau<br>Yermak Plateau"
+      },
+      "ocean trenches": {
+        "text": "note - there are no oceanic trenches on the Arctic sea floor"
+      },
+      "atolls": {
+        "text": "note - there are no atolls found in the Arctic Ocean"
+      }
     },
     "Elevation": {
       "highest point": {

oceans/zh.json

@@ -38,7 +38,7 @@
       }
     },
     "Major ocean currents": {
-      "text": "Clockwise North Atlantic Gyre consists of the northward flowing, warm Gulf Stream in the west, the eastward flowing North Atlantic Current in the north, the southward flowing cold Canary Current in the east, and the westward flowing North Equatorial Current in the south; the counterclockwise South Atlantic Gyre composed of the southward flowing warm Brazil Current in the west, the eastward flowing South Atlantic Current in the south, the northward flowing cold Benguela Current in the east, and the westward flowing South Equatorial Current in the north"
+      "text": "clockwise North Atlantic Gyre consists of the northward flowing, warm Gulf Stream in the west, the eastward flowing North Atlantic Current in the north, the southward flowing cold Canary Current in the east, and the westward flowing North Equatorial Current in the south; the counterclockwise South Atlantic Gyre composed of the southward flowing warm Brazil Current in the west, the eastward flowing South Atlantic Current in the south, the northward flowing cold Benguela Current in the east, and the westward flowing South Equatorial Current in the north"
     },
     "Bathymetry": {
       "continental shelf": {

oceans/zn.json

@@ -38,11 +38,11 @@
       }
     },
     "Major ocean currents": {
-      "text": "The clockwise North Pacific Gyre formed by the warm northward flowing Kuroshio Current in the west, the eastward flowing North Pacific Current in the north, the southward flowing cold California Current in the east, and the westward flowing North Equatorial Current in the south; the counterclockwise South Pacific Gyre composed of the southward flowing warm East Australian Current in the west, the eastward flowing South Pacific Current in the south, the northward flowing cold Peru (Humbolt) Current in the east, and the westward flowing South Equatorial Current in the north"
+      "text": "the clockwise North Pacific Gyre formed by the warm northward flowing Kuroshio Current in the west, the eastward flowing North Pacific Current in the north, the southward flowing cold California Current in the east, and the westward flowing North Equatorial Current in the south; the counterclockwise South Pacific Gyre composed of the southward flowing warm East Australian Current in the west, the eastward flowing South Pacific Current in the south, the northward flowing cold Peru (Humbolt) Current in the east, and the westward flowing South Equatorial Current in the north"
     },
     "Bathymetry": {
       "continental shelf": {
-        "text": "The <em>continental shelf</em> (see Figure 1), a rather flat area of the sea floor adjacent to the coast that gradually slopes down from the shore to water depths of about 200 m (660 ft). Dimensions can vary: they may be narrow or nearly nonexistent in some places or extend for hundreds of miles in others. The waters along the <em>continental shelf</em> are usually productive in both plant and animal life, both from sunlight and nutrients from ocean upwelling and terrestrial runoff. The following are examples of features found on the <em>continental shelf</em> of the Pacific Ocean.<br> <p>Arafura Shelf (Figure 4B)<br>Sahul Shelf (Figure 4B)<br>Sunda Shelf (Figure 4B)<br>Taiwan Banks (Figure 4B)<br><br></p>"
+        "text": "The <em>continental shelf</em> (see Figure 1), a rather flat area of the sea floor adjacent to the coast that gradually slopes down from the shore to water depths of about 200 m (660 ft). Dimensions can vary: they may be narrow or nearly nonexistent in some places or extend for hundreds of miles in others. The waters along the <em>continental shelf</em> are usually productive in both plant and animal life, both from sunlight and nutrients from ocean upwelling and terrestrial runoff. The following are examples of features found on the <em>continental shelf</em> of the Pacific Ocean.<br> <p>Arafura Shelf (Figure 5)<br>Sahul Shelf (Figure 5)<br>Sunda Shelf (Figure 5)<br>Taiwan Banks (Figure 5)<br><br></p>"
       },
       "continental slope": {
         "text": "The c<em>ontinental slope</em> (see Figure 1) is where the ocean bottom drops off more rapidly until it meets the deep-sea floor (<em>abyssal plain</em>) at about 3,200 m (10,500 ft) water depth. The deep waters of the <em>continental slope</em> are characterized by cold temperatures, low light conditions, and very high pressures. Sunlight does not penetrate to these depths, having been absorbed or reflected in the water above. The <em>continental slope</em> can be indented by submarine canyons, often associated with the outflow of major rivers. Another feature of the <em>continental slope</em> are alluvial fans or cones of sediments carried downstream to the ocean by major rivers and deposited down the slope. The following are examples of features found on the <em>continental slope</em> of the Pacific Ocean.<br> <p>Pribilof Canyon (Figure 2)<br>Zhemchug Canyon (Figure 2); note - deepest submarine canyon</p>"
@@ -54,10 +54,10 @@
         "text": "The <em>mid-ocean ridge </em>(see Figure 1), rising up from the <em>abyssal plain</em>, is an underwater mountain range, over 64,000 km (40,000 mi) long, rising to an average depth of 2,400 m (8,000 ft). <em>Mid-ocean ridges</em> form at divergent plate boundaries where two tectonic plates are moving apart and new crust is created by magma pushing up from the mantle. Tracing their way around the global ocean, this system of underwater volcanoes forms the longest mountain range on Earth. Fracture Zones are linear transform faults that develop perpendicular to the line of the mid-ocean ridge which can offset the ridge line and divide it into segments. The following are examples of <em>mid-ocean ridges</em> found on the floor of the Pacific Ocean.<br> <p>East Pacific Rise (Figure 3)<br>Pacific-Antarctic Ridge (Figure 3)</p>"
       },
       "seamounts": {
-        "text": "<em>Seamounts</em> (see Figure 1) are submarine mountains at least 1,000 m (3,300 ft) high formed from individual volcanoes on the ocean floor. They are distinct from the plate-boundary volcanic system of the <em>mid-ocean ridges</em>, because <em>seamounts</em> tend to be circular or conical. A circular collapse caldera is often centered at the summit, evidence of a magma chamber within the volcano. Flat topped <em>seamounts</em> are known as <em>guyots</em>. Long chains of <em>seamounts</em> are often fed by \"hot spots\" in the deep mantle. These hot spots are associated with stationary plumes of molten rock rising from deep within the Earth's mantle. These hot spot plumes melt through the overlying tectonic plate as it moves and supplies magma to the active volcanic island at the end of the chain of volcanic islands and <em>seamounts</em>. The following are examples of <em>seamounts</em> found on the floor of the Pacific Ocean.<br> <p>Caroline Seamounts (Figure 4B)<br>East Mariana Ridge (Figure 4)<br>Emperor Seamount Chain (Figure 2)<br>Hawaiian Ridge (Figure 2)<br>Lord Howe Seamount Chain (Figure 4)<br>Louisville Ridge (Figure 4)<br>Kapingamarangi (Ontong-Java) Rise (Figure 4B); note - largest submarine plateau<br>Macclesfield Bank (Figure 4B)<br>Marshall Seamounts (Figure 2)<br>Magellan Seamounts (Figure 2)<br>Mid-Pacific Seamounts (Figure 2)<br>Reed Tablemount (Figure 4B)<br>Shatsky Rise (Figure 2); note - third largest submarine plateau<br>Tonga-Kermadec Ridge (Figure 4)</p>"
+        "text": "<em>Seamounts</em> (see Figure 1) are submarine mountains at least 1,000 m (3,300 ft) high formed from individual volcanoes on the ocean floor. They are distinct from the plate-boundary volcanic system of the <em>mid-ocean ridges</em>, because <em>seamounts</em> tend to be circular or conical. A circular collapse caldera is often centered at the summit, evidence of a magma chamber within the volcano. Flat topped <em>seamounts</em> are known as <em>guyots</em>. Long chains of <em>seamounts</em> are often fed by \"hot spots\" in the deep mantle. These hot spots are associated with stationary plumes of molten rock rising from deep within the Earth's mantle. These hot spot plumes melt through the overlying tectonic plate as it moves and supplies magma to the active volcanic island at the end of the chain of volcanic islands and <em>seamounts</em>. The following are examples of <em>seamounts</em> found on the floor of the Pacific Ocean.<br> <p>Caroline Seamounts (Figure 5)<br>East Mariana Ridge (Figure 4)<br>Emperor Seamount Chain (Figure 2)<br>Hawaiian Ridge (Figure 2)<br>Lord Howe Seamount Chain (Figure 4)<br>Louisville Ridge (Figure 4)<br>Kapingamarangi (Ontong-Java) Rise (Figure 5); note - largest submarine plateau<br>Macclesfield Bank (Figure 5)<br>Marshall Seamounts (Figure 2)<br>Magellan Seamounts (Figure 2)<br>Mid-Pacific Seamounts (Figure 2)<br>Reed Tablemount (Figure 5)<br>Shatsky Rise (Figure 2); note - third largest submarine plateau<br>Tonga-Kermadec Ridge (Figure 4)</p>"
       },
       "ocean trenches": {
-        "text": "<em>Ocean trenches</em> (see Figure 1) are the deepest parts of the ocean floor and are created by the process of subduction. <em>Trenches</em> form along convergent boundaries where tectonic plates are moving toward each other, and one plate sinks (is subducted) under another. The location where the sinking of a plate occurs is called a subduction zone. Subduction can occur when oceanic crust collides with and sinks under (subducts) continental crust resulting in volcanic, seismic, and mountain-building processes. Subduction can also occur in the convergence of two oceanic plates where one will sink under the other and in the process create a deep <em>ocean trench</em>. Subduction processes in oceanic-oceanic plate convergence also result in the formation of volcanoes. Over millions of years, the erupted lava and volcanic debris pile up on the ocean floor until a submarine volcano rises above sea level to form a <em>volcanic island</em>. Such volcanoes are typically strung out in chains called island arcs. As the name implies, volcanic island arcs, which closely parallel the <em>trenches</em>, are generally curved. The following are examples of <em>ocean trenches</em> found on the floor of the Pacific Ocean.<br> <p>Aleutian Trench (Figure 2)<br>Chile Trench (Figure 3)<br>Izu-Ogasawara Trench (Figure 2)<br>Japan Trench (Figure 2)<br>Kermadec Trench (Figure 3, 4)<br>Kuril-Kamchatka Trench (Figure 2)<br>Manus Trench (Figure 4)<br>Mariana Trench (Figure 2, 4); note - deepest ocean trench<br>Middle America Trench (Figure 3)<br>Nansei-Shoto Trench (Figure 4B)<br>Palau Trench (Figure 2, 4)<br>Philippine Trench (Figure 4)<br>Peru-Chile Trench (Figure 3)<br>South New Hebrides Trench (Figure 4)<br>Tonga Trench (Figure 3, 4)<br>Yap Trench (Figure 2, 4)</p>"
+        "text": "<em>Ocean trenches</em> (see Figure 1) are the deepest parts of the ocean floor and are created by the process of subduction. <em>Trenches</em> form along convergent boundaries where tectonic plates are moving toward each other, and one plate sinks (is subducted) under another. The location where the sinking of a plate occurs is called a subduction zone. Subduction can occur when oceanic crust collides with and sinks under (subducts) continental crust resulting in volcanic, seismic, and mountain-building processes. Subduction can also occur in the convergence of two oceanic plates where one will sink under the other and in the process create a deep <em>ocean trench</em>. Subduction processes in oceanic-oceanic plate convergence also result in the formation of volcanoes. Over millions of years, the erupted lava and volcanic debris pile up on the ocean floor until a submarine volcano rises above sea level to form a <em>volcanic island</em>. Such volcanoes are typically strung out in chains called island arcs. As the name implies, volcanic island arcs, which closely parallel the <em>trenches</em>, are generally curved. The following are examples of <em>ocean trenches</em> found on the floor of the Pacific Ocean.<br> <p>Aleutian Trench (Figure 2)<br>Chile Trench (Figure 3)<br>Izu-Ogasawara Trench (Figure 2)<br>Japan Trench (Figure 2)<br>Kermadec Trench (Figure 3, 4)<br>Kuril-Kamchatka Trench (Figure 2)<br>Manus Trench (Figure 4)<br>Mariana Trench (Figure 2, 4); note - deepest ocean trench<br>Middle America Trench (Figure 3)<br>Nansei-Shoto Trench (Figure 5)<br>Palau Trench (Figure 2, 4)<br>Philippine Trench (Figure 4)<br>Peru-Chile Trench (Figure 3)<br>South New Hebrides Trench (Figure 4)<br>Tonga Trench (Figure 3, 4)<br>Yap Trench (Figure 2, 4)</p>"
       },
       "atolls": {
         "text": "<em>Atolls</em> are the remains of dormant volcanic islands. In warm tropical oceans, coral colonies establish themselves on the margins of the island. Then, over time, the high elevation of the island collapses and erodes away to sea level leaving behind an outline of the island in the form of the fringing coral reef. The resulting low island is typified by the coral reef surrounding a low elevation of sand and coral above sea level with an interior shallow lagoon. Often times the remaining dry land is broken into a ring of islets. Some lagoons can be hundreds of square kilometers. It may take as long as 300,000 years for an <em>atoll</em> formation to occur. <em>Guyots </em>are submerged atoll structures, which explains why they are flat topped seamounts. The following are examples of <em>atolls</em> found in the Pacific Ocean; for more information see the following entries in The World Factbook.<br><br>Federated States of Micronesia<br>French Polynesia<br>Kiribati<br>Marshall Islands<br>Midway Island<br>Tonga<br>Tuvalu<br>US Pacific Island Wildlife Refuges<br>Vanuatu<br>Wake Island"