101. Microbial Construction Of Siliceous Stalactites At Geysers And Hot Springs: Exam These waters mainly originate from geyser or hot spring discharge. The microbespreserved in the stalactites, however, imply that silica precipitation took http://palaios.geoscienceworld.org/cgi/content/abstract/16/1/73

Quick Search: advanced search GSW Home GeoRef Home My GSW Alerts ... TABLE OF CONTENTS Palaios ; February 2001; v. 16; no. 1; p. 73-94; DOI: 10.1669/0883-1351(2001)016 2.0.CO;2 SEPM Society for Sedimentary Geology This Article Figures Only Full Text Full Text (PDF) ... Citation Map Services Email this article to a friend Alert me to new issues of the journal Download to citation manager Cited by other online articles Search for citing articles in: ISI Web of Science (12) GeoRef GeoRef Citation Microbial Construction of Siliceous Stalactites at Geysers and Hot Springs: Examples from the Whakarewarewa Geothermal Area, North Island, New Zealand BRIAN JONES ROBIN W. RENAUT and MICHAEL R. ROSEN Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada Wairakei Research Centre, Institute of Geological and Nuclear Sciences, Wairakei Research Centre, Private Bag 2000, Taupo, New Zealand Siliceous stalactites, formed of opal-A laminae that are concentrically

102. Norris Geyser Basin It is the location of the tallest active geyser, colorful hot springs, If the mineral seals off a hot spring or geyser by accumulating in its vent, http://www.yellowstone.cc/norris.htm

Yellowstone National Park Norris Geyser Basin Norris Geyser Basin is the hottest and most changeable thermal area in Yellowstone. It is the location of the tallest active geyser, colorful hot springs, and microscopic life in one of the most extreme environments on earth. Rainbow Colors, hissing steam, and pungent odors combine to create an experience unique in Yellowstone. Porcelain Basin is open terrain with hundreds of densely packed geothermal features; in contrast, Back Basin is forested and its features are more scattered and isolated. The Norris Geyser Basin is made up of two major parts: the Porcelain Basin and the Back Basin. Porcelain Basin: This basin consists of a whitish rock-sheet that pulsates from the pressure of steam and boiling water beneath it. A number of its geysers and other features have been born suddenly in small hydrothermal explosions. Some features are ephemeral, their activity lasting a few hours, days, or even weeks. The hottest of Yellowstone's geothermal features are steam vents (fumaroles). Black Growler Steam Vent, on the hillside in front of you, has measured 199 to 280 degrees F (93 to 138 degrees C). A plentiful water supply would help cool these features; however, steam vents are usually found on hillsides or higher ground, above the basin's water supply. They rapidly boil away what little water they contain, releasing steam and other gases forcefully from underground. Ledge is the second largest geyser in the Norris Geyser Basin, capable of shooting water125 feet into the air. Because it erupts at an angle, however, the water will sometimes reach the ground 220 feet away. It has at times in the past erupted at regular intervals of 14 hours. The geyser became inactive between 1979 and late 1993. It erupted on a fairly regular cycle of every four to six days in 1994 and 1995.

103. Yellowstone National Park Hot Springs or sinter, creating the massive geyser cones; the scalloped edges of hot springs; hot springs with names like Morning Glory, Grand Prismatic, Abyss, http://www.yellowstoneparknet.com/geothermal_features/hot_springs.php

TRAVEL GUIDES : Yellowstone Grand Teton Big Sky Bozeman Cody Jackson Hole Red Lodge West Yellowstone Yellowstone National Park Hot Springs home site map about us request a link ... WIN A TRIP! supporters Snowmobile Tours, JH RV Parks / Campgrounds Yellowstone Lodging Attractions ... SEND THIS PAGE TO A FRIEND Hot Springs In the high mountains surrounding the Yellowstone Plateau, water falls as snow or rain and slowly percolates through layers of porous rock, finding its way through cracks and fissures in the earth's crust created by the ring fracturing and collapse of the caldera. Sinking to a depth of nearly 10,000 feet, this cold water comes into contact with the hot rocks associated with the shallow magma chamber beneath the surface. As the water is heated, its temperatures rise well above the boiling point to become superheated. This superheated water, however, remains in a liquid state due to the great pressure and weight pushing down on it from overlying rock and water. The result is something akin to a giant pressure cooker, with water temperatures in excess of 400°F. Hot Spring The highly energized water is less dense than the colder, heavier water sinking around it. This creates convection currents that allow the lighter, more buoyant, superheated water to begin its slow, arduous journey back toward the surface through rhyolitic lava flows, following the cracks, fissures, and weak areas of the earth's crust. Rhyolite is essential to geysers because it contains an abundance of silica, the mineral from which glass is made. As the hot water travels through this "natural plumbing system," the high temperatures dissolve some of the silica in the rhyolite, yielding a solution of silica within the water.

104. Molossian Institute Of Volcanology - Long Valley Caldera Within weeks geyser activity had waned, but the hot springs remain today.The origin of the new hot springs remains unclear, but it has been noted that they http://www.molossia.org/volcanology/longvalley.html

Molossian Institute of Volcanology LONG VALLEY CALDERA California Geologic Background of the Long Valley Caldera Mammoth Mountain, at 3389 meters (11,050 feet), is a composite volcano made up of about 12 rhyodacite and quartz latite domes extruded along the southwest rim of Long Valley caldera from 200,000 to 50,000 years ago. Mammoth Mountain is one of the eruptive centers that developed late in the evolutionary cycle of the Long Valley caldera complex. Volcanic unrest continues at Long Valley. Earthquake activity began in 1978 and culminated in mid-May 1980 when four magnitude 6 events were recorded in a 2-day period. Volcanologists interpreted the earthquakes, accompanying ground deformation, and an increase in activity at fumaroles as an indication of magma movement beneath the caldera. U.S. Geological Survey continues to monitor the caldera. Inyo Craters Three large craters comprise the Inyo Craters: Two lake-filled craters (North and South Inyo Craters) and another crater at the summit of Deer Mountain (Summit Crater), the peak to the north. The two craters with lakes (North and South Inyo Craters) are over 184 meters (600 feet) in diameter. The northern crater is about 46 meters (150 feet) deep and the southern one over 61 meters (200 feet) deep. The Inyo Craters chain also includes nine much smaller craters and at least five volcanic domes. Inyo Craters are phreatic explosion craters. They were created about 500 years ago as phreatic explosion pits, rather than typical ash eruptions. The explosive formation of the craters was probably triggered when circulating groundwater was heated by the underlying magma to the point that fluid pressure exceeded confining pressure. The superheated water vaporized and the expanding steam hurled the overlying material upward and outward blanketing the area with a layer of debris up to 15 meters (50 feet) thick. No lava was emitted from this eruption. Such eruptions are termed hydroclastic eruptions because they involve rock fragmented rocks and water.

105. Geysers And Hot Springs The Universe Theater Hotsprings and geysersFor more information on this subject visit our Weird Geology geysers page.and the Geyser Field Formations page. This movie requires the FLASH plug-in. http://library.thinkquest.org/17457/volcanoes/features.geysers.php?tqskip1=1

106. Hot Spring - Wikipedia, The Free Encyclopedia Green Dragon Spring at Norris Geyser. A hot spring or a hydrothermal spring isa place where warm or hot groundwater issues from the ground on a regular http://en.wikipedia.org/wiki/Hot_spring

Hot spring From Wikipedia, the free encyclopedia. Green Dragon Spring at Norris Geyser A hot spring or a hydrothermal spring is a place where warm or hot groundwater issues from the ground on a regular basis for at least a predictable part of the year , and is significantly above the ambient ground temperature (which is usually around 55–57 °F or 13–14 °C in the eastern United States Contents Sources of heat Therapeutic uses North American hot springs Native Americans and hot springs ... edit Sources of heat The water issuing from a hot spring is heated by geothermal heat, essentially heat from the Earth 's interior. In general, the temperature of rocks within the earth increases with depth. The rate of temperature increase with depth is known as the geothermal gradient . If water percolates deeply enough into the crust, it will be heated as it comes into contact with hot rocks. The water from hot springs in non- volcanic areas is heated in this manner. In volcanic zones such as Yellowstone National Park , water may be heated by coming into contact with magma (molten rock). The high temperature gradient near magma may cause water to be heated enough that it boils or becomes

107. GOSA Transactions Volume IV, Abstracts s of the Geyser Hill Wave,......Cyclic hot Spring Activity on Geyser Hill, Upper Geyser Basin, Yellowstone NationalPark—Graphical and Interpretive http://www.geyserstudy.org/t4_abstracts.htm

GOSA Transactions Volume IV Abstracts About GOSA GOSA Press Ordering Information GOSA Home Page ... GOSA Transactions Yellowstone Geysers Known Active in 1992 T. Scott Bryan Transactions Ordering Information T. Scott Bryan Abstract: In an effort to better understand the complex relationships between geysers and other thermal features on Geyser Hill, a comprehensive study of eruptive and water level variations was conducted during July, 1992. The results show that there are both long-term and daily (diurnal) cycles superimposed on a general but slight randomness. The causes of these apparently independent cycles are speculated on. Transactions Ordering Information Evidence for the Geyser Hill Wave and Diurnal Effects on Geyser Hill During the 1980s T. Scott Bryan Abstract: An examination of eruption interval data for Giantess and Beehive Geysers during 1981-1983 and for Plume Geyser during 1989-1990 indicates that the Geyser Hill Wave has been in operation during this entire span of time in a fashion similar to that observed during 1992. A similar look at miscellaneous Plume Geyser data shows that its diurnal effect was either absent or only weakly present until 1989. Transactions Ordering Information Why Mortar is Fan: An Analysis of the History of the Fan and Mortar Geyser Complex Paul Strasser Abstract: Most geyser aficionados have considered the historic record of the section of the Upper Geyser Basin extending from Fan Geyser to Riverside Geyser as essentially complete and understood. Specific records of geyser activity in this area extend back to the Washbum-Langford- Doane expedition of 1870; members of this expedition named a feature "Fan Geyser" and reported one of its displays.

108. Hot Spring: Definition And Much More From Answers.com Green Dragon Spring at Norris Geyser. A hot spring is a place where warm or hotgroundwater issues from the ground on a regular basis for at least a http://www.answers.com/topic/hot-spring

showHide_TellMeAbout2('false'); Business Entertainment Games Health ... More... On this page: Dictionary Encyclopedia WordNet Wikipedia Mentioned In Or search: - The Web - Images - News - Blogs - Shopping hot spring Dictionary hot spring n. A natural spring producing warm water, usually at a temperature above that of the human body. var tcdacmd="cc=edu;dt"; Encyclopedia hot spring, natural discharge of groundwater having an elevated temperature. Most hot springs result from the emergence of groundwater that has passed through or near recently formed, hot, igneous rocks. Iceland, Yellowstone Park in the United States, and North Island of New Zealand are noted for their hot springs. In recent years the depletion of fossil fuels has resulted in a renewed interest in utilizing the energy contained in hot springs. This type of geothermal energy is already being utilized in California, Italy, and Iceland. See energy, sources of WordNet Note: click on a word meaning below to see its connections and related words. The noun hot spring has one meaning: Meaning #1 a natural spring of water at a temperature of 70 F or above Synonym: thermal spring Wikipedia hot spring Green Dragon Spring at Norris Geyser A hot spring is a place where warm or hot groundwater issues from the ground on a regular basis for at least a predictable part of the year , and is significantly above the ambient ground temperature (which is usually around 55~57°F or 13~14°C in the eastern United States Sources of heat The water issuing from a hot spring is heated by

109. NOMINATION OF E He also measured hot spring and geyser activity for several years at Taupo Spa,and observed the obvious decline in activity due to exploitation of the http://www.gsnz.org.nz/gs_archive/gsprlk.htm

NOMINATION OF E.F.LLOYD AND R.KEAM FOR NEW ZEALAND SCIENCE AND TECHNOLOGY MEDALS The Geological Society of New Zealand is pleased to nominate E.F. (Ted) Lloyd and R.F (Ron) Keam jointly for their outstanding contribution to geothermal and volcanological science over a period of 50 years. During this time they have mapped, described and analysed geothermal fields and volcanic areas in the Rotorua-Taupo area, and actively applied this knowledge to the conservation of geothermal features. New Zealand is recognised worldwide as an area of outstanding geothermal attractions, including surface phenomena such as geysers and hot springs. On a worldwide scale, it is only surpassed by Yellowstone National Park in the USA. The geothermal features are important as unique scenic attractions, for their cultural significance, as sources of energy, and as scientific phenomena. Over the years there have been clashes of interest in these values. Without the advocacy of Lloyd and Keam, sometimes at considerable personal difficulty, it is likely that there would be no geysers remaining in this country, and that the number of hot springs would be far fewer. Since European colonisation many geothermal features have been lost, and most of the remainder are under threat. As an illustration, of the five major geyser fields in existence 120 years ago (Rotomahana, Whakarewarewa, Orakeikorako, Wairakei, and Taupo Spa), only Whakarewarewa survives with any significant number of active geysers. Rotomahana was destroyed by the 1886 Tarawera eruption, but Orakeikorako, Wairakei, and Taupo Spa were eliminated as geyser fields by human activity. Of the 130 significant geysers known to be active in 1950, fewer than 15 (mostly at Whakarewarewa) are still erupting today.

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