Geysers and Hot springs,Wonders of Geology

Hot Springs

A hot spring is a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust. There are geothermal hot springs in many locations all over the crust of the earth.
The water issuing from a hot spring is heated by geothermal heat, i.e., heat from the Earth's mantle. 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.

Grand Prismatic Spring 

In active 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 superheated. If the water becomes so hot that it builds steam pressure and erupts in a jet above the surface of the Earth, it is called a geyser. If the water only reaches the surface in the form of steam, it is called a fumarole. If the water is mixed with mud and clay, it is called a mud pot.
Note that hot springs in volcanic areas are often at or near the boiling point. People have been seriously burned and even killed by accidentally or intentionally entering these springs.

Warm springs are sometimes the result of hot and cold springs mixing but may also occur outside of volcanic areas, such as Warm Springs, Georgia (frequented for its therapeutic effects by paraplegic U.S. President Franklin D. Roosevelt, who built the Little White House there).
Geysers and hot springs are natural features resulting when ground water is heated by geothermal forces and brought to the surface. They provide a spectacular sight of boiling water eruptions, vivid colors and strange formations. However, for the hot spring aficionado, the greatest pleasure comes not from just looking at the spring, but from getting into the water for its therapeutic powers. 

Hot springs are the areas where water is constantly boiling inside a hole or heated pond. While Geyser is a hole where water is always rising into the air and then rising up again.  Geysers   Geysers are hot springs with constrictions in their plumbing, usually near the surface, that prevent water from circulating freely to the surface where heat would escape. The deepest circulating water can exceed the surface boiling point (199°F/93°C). Surrounding pressure also increases with depth, much as it does with depth in the ocean. Increased pressure exerted by the enormous weight of the overlying water prevents the water from boiling. As the water rises, steam forms. Bubbling upward, the steam expands as it nears the top of the water column. At a critical point, the confined bubbles actually lift the water above, causing the geyser to splash or overflow. This decreases pressure on the system, and violent boiling results. Tremendous amounts of steam force water out of the vent, and an eruption begins. Water is expelled faster than it can enter the geyser's plumbing system, and the heat and pressure gradually decrease. The eruption stops when the water reservoir is depleted or when the system cools.   Gaysers    Geysers are some of the most unusual geologic phenomena in the world. They are incredible natural fountains that can shoot boiling hot water and steam hundreds of feet into the sky in violent eruptions. While most geyser eruptions last only a few minutes, some last for days. Some geysers almost never stop. Others erupt violently, then stay dormant for years or even decades. While geysers are rare (there are less than 700 known geysers in the world) they are not impossible for the average person to observe. They exist on every continent in the world, except Antarctica. The premiere place to see geysers, however, is Yellowstone National Park in the United States. Yellowstone is home to more than half of all the geysers on planet Earth. Technically the U.S. Geological Survey defines a geyser as: A hot spring characterized by intermittent discharge of water ejected turbulently and accomplished by a vapor phase. What makes a geyser act the way it does? In order for a geyser to exist, there are four specific conditions that must be met. First, there must be an abundant supply of surface water over a long period of time. It is estimated that Yellowstone's geysers discharge a staggering seventy-million gallons of water a day. The water a geyser ejects comes from snow and rain. When precipitation hits the ground, most of it runs off into rivers and streams. A small portion, perhaps five percent, soaks into the ground. Moving slowly through tiny cracks it finds its way into the underground tunnels that make up the plumbing of a geyser, then is shot to the surface during an eruption. Travel from the surface down through the rock and out through a geyser eruption can take 500 years. Water we see today shooting out of geysers fell from the sky in the time of Columbus.  Secondly, there must be a volcanic heat source. All geyser field sites are above recently active volcanic areas. The surface water works its way down to a depth of around 7,000 feet where it meets up with hot rocks. The water is heated up to 500 degrees Fahrenheit or more, but cannot turn into steam because of the pressure it is under. Though the water is hot and under pressure it would never be ejected from geysers with such tremendous force if it were not for the special quality of the rocks in the geyser fields. The rocks produce a material called geyserite. Geyserite, which is the third necessary condition, is mostly silicon dioxide, is dissolved from the rocks and deposited on the walls of the geyser's plumbing system and on the surface around the geyser. The deposits make the channels carrying the water up to the surface pressure-tight. This allows the pressure to be carried all the way to the top and not be leaked out into the loose gravel, soil or sand that are normally under the geyser fields.  The final condition needed to produce a geyser is a plumbing system below it with a special shape. All springs must have a set of channels below them that allow water to flow to the surface. In a geyser there must be a constriction at some point near the top. The water sitting in this narrow spot acts as a valve or lid that allows pressure to build up in the water below. When enough pressure builds up to overcome the constriction, the geyser erupts. The need for the right combination of conditions: abundant water, volcanic heat, geyserite and a special underground shape, are why geysers are so rare. If there is heat, but not enough water a fumarole appears. A fumarole is a steam vent. There is so little water in this type of hot spring that while coming to the surface it boils away, and all that you see is a hole in the ground with steam coming out of it, often accompanied by a roaring or rushing sound. Fumaroles often have the smell of "rotten eggs" because small amounts of hydrogen sulfide get mixed in with the steam. A fumarole that comes up in a wet surface area can become a mud pot. As the steam bubbles up through the water, the hydrogen coming up with the steam reacts with the water to form sulfuric acid. This melts the surrounding rock to turn the water into a muddy clay. Mud pots bubble and can throw lumps of clay for some distance when they are active. fumarole The Most Famous Gysers and Hotspring around world   They provide a spectacular sight of boiling water eruptions, vivid colors and strange formations. However, for the hot spring aficionado, the greatest pleasure comes not from just looking at the spring, but from getting into the water for its therapeutic powers.  Beppu   Is one of Japan’s most famous hot spring resorts with the largest volume of hot water in the world apart from Yellowstone in the United States and the largest number of hot spring sources in Japan. Beppu contains 9 nine spectacular hot springs, which are sometimes referred to as the “nine hells of Beppu”, and are for viewing rather than bathing. The most photogenic of the nine hells is the “Blood Pond Hell” featuring a pond of hot, red water.  Rincón de la Vieja     Rincón de la Vieja is an active volcano in north-western Costa Rica. Its name means “The Old Woman’s Corner”, a reference to a local legend about a girl whose lover was thrown into the crater by her father. The last serious eruption was in 1983. Large number of hot springs and areas of bubbling mud are found on the slopes of the volcano. The mud has minerals and medicinal properties used in cosmetology.  Valley of Geysers   Situated on the Kamchatka Peninsula in the Russian Far East, the Valley of Geysers is the second largest geyser field in the world. The Valley of Geysers was discovered in 1941 by local scientist Tatyana Ustinova. Since then it became a popular tourist attraction in Kamchatka. The Valley of Geysers has suffered significantly from a landslide in 2007 which buried about half of all geysers. Nevertheless, the Valley is still alive and attracts a lot of interest from scientists and tourists. El Tatio       Is a famous geyser field situated within the Andes Mountains of northern Chile at a height of 4,300 meters (13,780 feet). The climatic conditions and high altitude make the geyser field one of the most extreme environments on Earth. With over 80 active geysers, El Tatio is also the largest geyser field in the southern hemisphere and the third largest field in the world. Despite the icy cold weather many visitors take a dip in the hot springs.  Rotorua     Sits on the shores of Lake Rotorua of New Zealand. It is known as the thermal wonderland of New Zealand. There are numerous geysers and hot springs in and around the city. Many of these are in parks and reserves. Natural eruptions of steam, hot water and mud occasionally occur in new locations. Nearby Wai-O-Tapu has many famous hot springs noted for their colourful appearance, in addition to the Lady Knox Geyser.  Huanglong  Huanglong (Yellow Dragon Mountain ) is an area in central China known for its colorful pools formed by calcite deposits, as well as diverse forest ecosystems, snowcapped peaks, hot springs and waterfalls. Huanglong is also home to many endangered species including the famous Giant Panda. Pearl Boiling Lake, a hot, medical, mineral spring with a temperature of at 21°C is located at the south part of Huanglong. The best time of year to visit the terraced limestone ponds is September and October when blue, yellow, white and green ponds can be seen.  Geysers of Haukadalur   I  s a valley that contains the largest and most famous Geysers in Iceland, including Geysir and Strokkur. Geysir is the earliest geyser known to Europeans and gave rise to the word Geyser. Eruptions at Geysir can hurl boiling water up to 70 meters in the air. Eruptions may be infrequent however, and have in the past stopped altogether for years at a time. At the moment Geysir erupts around 3 times per day. Strokkur, which is less than 50 meters from Geysir erupts every 10 minutes or so.  Pamukkale  Pamukkale, meaning “cotton castle” in Turkish, is an unreal landscape famous for its white terraces. The terraces are made of travertine, a sedimentary rock deposited by water with a very high mineral content from the hot springs. People have bathed in its pools for thousands of years and continue to be one of top attractions in Turkey. The ancient Greek city of Hierapolis was built on top of the hot springs by the kings of Pergamon. The ruins of the baths, temples and other Greek monuments can be seen at the site.  Jigokudani Monkey Park    Is a famous hot spring area near Nagano, Japan. The name Jigokudani (meaning “Hell’s Valley”), is due to steam and boiling water that bubbles out the frozen ground, surrounded by steep cliffs and formidably cold and hostile forests. It is famous for its large population of wild Snow Monkeys that go to the valley during the winter when snow covers the park. The monkeys descend from the steep cliffs and forest to sit in the warm waters of the onsen (hot springs), and return to the security of the forests in the evenings.     Dallol    Is a volcanic explosion crater in the Danakil Depression, in Ethiopia. It was formed during a volcanic eruption in 1926, and numerous other similar craters dot the salt flats nearby. This remote area is subject to the highest average temperatures on the planet with an average annual temperature of 34°C (94°F) recorded between the years 1960 and 1966. Dallol resembles the famous hot springs areas of Yellowstone Park but appears to be more wide-stretching.  Blue Lagoon    Is a Geothermal Spa located in a lava field between Keflavik Internation Airport and Reykjavik in southwestern Iceland. The lagoon is a byproduct of the nearby geothermal power plant. Superheated water is vented from the ground near a lava flow and used to run turbines that generate electricity. After going through the turbines, the hot water passes through a heat exchanger to provide heat for a municipal hot water heating system and is finally fed into the lagoon. The warm waters are rich in minerals and bathing in the Blue Lagoon is reputed to help many people suffering from skin diseases. The water temperature in the bathing and swimming area of the lagoon averages 40 °C (104 °F) and is enjoyable year round, even in freezing conditions.  Yellowstone   Yellowstone National Park was the world’s first national park, set aside in 1872 to preserve the vast number of geysers, hot springs, and other thermal areas, as well as to protect the incredible wildlife and rugged beauty of the area. Yellowstone lies on top of a gigantic hotspot where light, hot, molten mantle rock rises towards the surface. Subsequently, the park contains half of all the world’s known geothermal features, with more than 10,000 examples of geysers and hot springs. Over the past 17 million years or so, this hotspot has generated a succession of violent eruptions including a dozen or so super eruptions. The last full-scale eruption of the Yellowstone volcano happened nearly 640,000 years ago. Related Videos