auto-update week 46

oceans/zn.json

@@ -29,9 +29,6 @@
     "Climate": {
       "text": "planetary air pressure systems and resultant wind patterns exhibit remarkable uniformity in the south and east; trade winds and westerly winds are well-developed patterns, modified by seasonal fluctuations; tropical cyclones (hurricanes) may form south of Mexico from June to October and affect Mexico and Central America; continental influences cause climatic uniformity to be much less pronounced in the eastern and western regions at the same latitude in the North Pacific Ocean; the western Pacific is monsoonal - a rainy season occurs during the summer months, when moisture-laden winds blow from the ocean over the land, and a dry season during the winter months, when dry winds blow from the Asian landmass back to the ocean; tropical cyclones (typhoons) may strike southeast and east Asia from May to December"
     },
-    "Terrain": {
-      "text": "<p>surface dominated by two large gyres (broad, circular systems of currents), one in the northern Pacific and another in the southern Pacific; in the northern Pacific, sea ice forms in the Bering Sea and Sea of Okhotsk in winter; in the southern Pacific, sea ice from Antarctica reaches its northernmost extent in October; the ocean floor in the eastern Pacific is dominated by the East Pacific Rise, while the western Pacific is dissected by deep trenches, including the Mariana Trench, which is the world's deepest at 10,924 m</p> <p><strong>major surface currents:</strong> 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</p>"
-    },
     "Ocean volume": {
       "ocean volume": {
         "text": "669.88 million cu km"
@@ -40,6 +37,32 @@
         "text": "50.1%"
       }
     },
+    "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"
+    },
+    "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>"
+      },
+      "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>"
+      },
+      "abyssal plains": {
+        "text": "The a<em>byssal 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 Pacific Ocean.<br> <p>Aleutian Basin (Figure 2)<br>Central Pacific Basin (Figure 2)<br>Northeast Pacific Basin (Figure 2)<br>Northwest Pacific Basin (Figure 2)<br>Philippine Basin (Figure 4)<br>Southwest Pacific Basin (Figure 4)<br>Tasman Basin (Figure 4)</p>"
+      },
+      "mid-ocean ridge": {
+        "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>"
+      },
+      "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>"
+      },
+      "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"
+      }
+    },
     "Elevation": {
       "highest point": {
         "text": "sea level"