Hot spot: scientists prove beneath Yellowstone and find a seething volcanic basin that could one day blow its top. (Earth Science Volcanoes).TOWERS OF scalding scalding plunging of pig or poultry carcasses into very hot water to facilitate scraping and dehairing and plucking. Chicken scalding water is 130°F for broilers (larger birds higher) applied for 1 to 2 minutes. Modern pig abattoirs use steam at 144 to 147°F for about 3 minutes. water gush up from the ground hundreds of meters into the sky. Bubbling mud ponds belch belch v. To expel stomach gas noisily through the mouth; burp. steaming gases from below. A scene from Middle Earth in the movie Lord of the Rings? No, it's Yellowstone National Park Yellowstone National Park, 2,219,791 acres (899,015 hectares), the world's first national park (est. 1872), NW Wyo., extending into Montana and Idaho. It lies mainly on a broad plateau in the Rocky Mts., on the Continental Divide, c. , home to more than 10,000 hot springs and geysers The examples and perspective in this USA may not represent a worldwide view of the subject. Please [ improve this article] or discuss the issue on the talk page. This is an alphabetical list of notable geysers, a type of erupting hot spring: tr.v. su·per·heat·ed, su·per·heat·ing, su·per·heats 1. To heat excessively; overheat. 2. fountains) that draw hordes of gaping tourists from all over the world. What many tourists don't realize is that cradling this awesome landscape is a caldera caldera: see crater. caldera Large, bowl-shaped volcanic depression that forms when the top of a volcanic cone collapses into the space left after magma is ejected during a violent volcanic eruption. The term is Spanish for “caldron. , the craterlike basin of a volcano, that is still active--and could one day explode again. Feeding the volcano is the "Yellowstone hot spot," a sizzling column of partly melted rock that extends about 20 kilometers (12.5 miles) across and 2,900 km (1,802 mi) down, nearly halfway to the center of Earth. This hot spot created the caldera and provides the heat source that fuels the park's famed geysers and hot springs. Scientists are taking a closer look at the hot spot (one of about 40 in the world) to learn how Earth's heated interior molds the planet's surface. One surprising discovery to date: The hot spot actually causes the volcanic basin to "breathe," or rise and sink in cycles, like a poorly baked cake in an oven. Even the bottom of tranquil Yellowstone Lake, where tourists lazily fish trout, bulges and deflates. In other words Adv. 1. in other words - otherwise stated; "in other words, we are broke" put differently , the rise and fall triggered by the Yellowstone hot spot could one day lead to a monster explosion of steam from many geysers and a tidal wave in the lake. "You don't want to be around when something happens," says Ken Pierce of the U.S. Geological Survey (USGS USGS United States Geological Survey (US Department of the Interior) ) in Denver. RESTLESS GIANT Three major volcanic explosions gave birth to Yellowstone as it exists today. The first one, more than 2 million years ago, was one of the largest eruptions in the planet's history, blanketing the entire Western U.S. with ash nearly one meter (3.3 feet) thick. A second eruption took place about 1.3 million years ago, followed by a third, 640,000 years ago, which formed the present-day caldera. Extending about 48 km (30 mi) across, the caldera now occupies center stage at Yellowstone (see map, p. 18). [ILLUSTRATION OMITTED] "The caldera was like a blister underneath Earth's crust [outermost out·er·most adj. Most distant from the center or inside; outmost. outermost Adjective furthest from the centre or middle Adj. 1. layer]," explains park ranger Mark Williams. A mass of molten rock, or magma, heated deep within Earth, thrust up the crust and formed a bulge. When the pressure got too great, the magma exploded and the dome collapsed in on itself to create a caldera. But the Yellowstone hot spot continues to push up against the crust, causing the caldera to heave and sink (see diagrams, p. 19). [ILLUSTRATION OMITTED] HEAVY BREATHER With the lung capacity of a whale five times the size of New York City New York City: see New York, city. New York City City (pop., 2000: 8,008,278), southeastern New York, at the mouth of the Hudson River. The largest city in the U.S. , an "inhaling" (rising) caldera can lift 320 sq km (124 sq mi) of land as much as 30.5 m (100 ft). In the last 9,000 years the caldera has "inhaled" and "exhaled" about five times, says Pierce. By measuring the ancient shorelines of Yellowstone Lake, he determined that the caldera rose and fell each time by an average of 7.6 m (25 ft). Pierce says it's currently exhaling ex·hale v. ex·haled, ex·hal·ing, ex·hales v.intr. 1. a. To breathe out. b. To emit air or vapor. 2. To be given off or emitted. v.tr. , deflating at a rate of about 1 cm (0.4 in.) a year. (Yet other evidence is contradictory. Newly installed sensors suggest the caldera may continuously rise and fall. The sensors reveal that in 1987 the caldera started to fall by 2.5 cm, or 1 in., a year. But in 1995 the caldera began to bulge again.) Pierce is waiting to see if the current release of pressure could result in a violent explosion at the surface. An exhale exhale /ex·hale/ (eks´hal) to breathe out. ex·hale v. 1. To breathe out. 2. To emit a gas, vapor, or odor. sometimes triggers a blast of boiling hot water and steam that might scald an area about 1.6 to 3.2 km (1 to 2 mi) across. Meanwhile, scientists watch for other signs of volcanic eruption. Geologists have scanned 40 percent of the Yellowstone Lake bottom with sound waves, remote-control devices, and scuba gear. Their discovery: The lake bed's rise and fall could also unleash steam explosions and wild waves. And a fault line (crack in Earth's crust) has been found to run right into the lake bed. "We could see earthquakes, and the ground would swell tens of meters," says USGS geologist Robert Christiansen. "There's no reason for tourists not to go to Yellowstone right now," he quickly adds. "But another eruption will occur sometime within the next 100,000 years." [ILLUSTRATION OMITTED] Cross-Curricular Connection History: Research and report on some of the most disastrous volcanic eruptions in history. Did You Know? * Each year Yellowstone's caldera emits as much carbon dioxide as 10 to 20 fossil fuel plants, killing many animals and small patches of forest. * Most hot spots lie beneath the ocean floor. Island chains, like the Hawaiian Islands, are often formed when magma erupts from underwater hot spots. * In May 2001, Yellowstone was made one of the nation's official volcano observatories. Together with four other U.S. Geological Survey observatories in Alaska, California, the Pacific Northwest, and Hawaii, it monitors 43 of approximately 70 potentially hazardous volcanoes in the U.S. Directions: Circle the correct word in the parentheses See parenthesis. parentheses - See left parenthesis, right parenthesis. . 1. Cradling Yellowstone National Park is a (caldera, geyser geyser (gī`zər) [Icel.], hot spring from which water and steam are ejected periodically to heights ranging from a few to several hundred feet. , hot spring). 2. There are approximately (20, 40, 70) volcanic hot spots in the world. 3. The center of the Earth is approximately (20, 3,000, 6,400) kilometers below the (shell, crust, coat). 4. Molten rock under Earth's surface is called (lava, magma, ooze). 5. A(n) (inhaling, exhaling, pregnant) caldera is one that is rising. ANSWERS 1. caldera 2. 40 3. 6,400, crust 4. magma 5. inhaling National Science Education Standards The National Science Education Standards (NSES) are a set of guidelines for the science education in primary and secondary schools in the United States, as established by the National Research Council in 1996. Grades 5-8: structure of the Earth system * Earth's history * natural hazards Grades 9-12: energy in the Earth system * natural and human-induced hazards Resources Visit the Yellowstone Volcano Observatory: volcanoes.usgs.gov/yvo/ The University of North Dakota's Volcano World Web site is packed with information and teaching tips: volcano.und.nodak.edu HANDS-ON SCIENCE GASSY gas·sy adj. gas·si·er, gas·si·est 1. Containing or full of gas. 2. Resembling gas. 3. Slang Bombastic; boastful. BLOW-UP How can gas in soda blow up a balloon? Find out! YOU NEED: unopened 1-liter plastic bottle of cola * round balloon * tape TO DO: 1 Slowly unscrew the cap on the soda bottle. You'll notice some bubbles appear on the soda as you release the pressure inside the bottle by opening the cap. These bubbles come from carbon dioxide that was dissolved in the soda under pressure. 2 Fasten the balloon's mouth to the bottle's neck. Secure the balloon with tape. 3 Press your hand over the bottle's mouth so that the balloon hangs to the side as shown. Gently shake the bottle to dissolve gas into the soda. 4 Take your hand off the bottle. What happens to the soda? To the balloon? CONCLUSIONS: How is the soda similar to magma? How is the balloon similar to Yellowstone's caldera? DON'T STOP NOW! Observe the balloon. How long does it take for the balloon to deflate (file format, compression) deflate - A compression standard derived from LZ77; it is reportedly used in zip, gzip, PKZIP, and png, among others. Unlike LZW, deflate compression does not use patented compression algorithms. ? |
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