Shield volcanoes are tall and broad with flat, rounded shapes. They have low slopes and almost always have large craters at their summits.Shield volcanoes can be very big. An example is Mt. Kilauea (in Hawaii, USA).
Shield volcanoes are built almost entirely of fluid lava flow. Flow after flow pours out in all directions from a central summit vent, which builds a broad, gently sloping cone - much like a warrior's shield or a plateau.As the lava cools, it dips down in the center leaving sloped sides, like a bowl or a shield.These volcanoes do not explode the way composite volcanoes do; instead, lava just flows out of them.Their eruptions consist of hot, flowing basaltic lava that travels a long way before it solidifies.
Many volcanoes that form above hot spots are shield volcanoes.
Shield volcanoes have much smaller eruptions producing less ash. However they pour out a lot more lava over a long period of time.
Olympus Mons is, a giant shield volcano on Mars. It is believed to be the largest volcano in the solar system.
Mauna Loa, a shield volcano on the "big" island of Hawaii, is the largest single mountain in the world, rising over 30,000 feet above the ocean floor and reaching almost 100 miles across at its base.
However some volcanoes like Mauna Loa stay active and erupt much more often.The Hawaiian volcano of Kilauea has thrown lava nearly 2,000 feet into the air.
Saturday, March 26, 2011
Friday, March 25, 2011
Composite volcanoes
Composite volcanoes have a principal conduit system through which magma from a reservoir deep in the Earth's crust rises to the surface repeatedly to cause eruptions.Composite volcanoes, sometimes called stratovolcanoes, tend to erupt explosively because of the silica-based nature of magmas associated with these volcanoes.
Composite volcanoes often form the largest and tallest volcanoes. They are the most explosive and dangerous of the types of volcanoes.
Most of the tall volcanoes, like Mount St. Helens and Mount Rainier in Washington and Mount Fuji in Japan are composite volcanoes. These volcanoes usually have a big explosion when they erupt, and in-between eruptions you might not even be able to tell they are volcanoes, because they are very quiet and look just like other
mountains.
Shape is largely a function of slope angle; at the one
extreme are very shallow slopes that characterize shields, and on the other are the steeper slopes that characterize cones and domes. Among the smaller edifices are cinder cones and domes, which are typically monogenetic (formed from a single eruption episode).
Compared with caldera systems, composite volcanoes erupt smaller volumes more frequently and less explosively, which likely inhibits the long-term extreme differentiation, which typifies caldera-forming magmas.Young stratovolcanoes are typically steep sided and symmetrically cone shaped. There are several active stratovolcanoes in North America. Since 1980 Mount Saint Helens in Washington has become the most familiar.dimension built of alternating layers of lava flow, volcanic ash and cinders.
Famous composite volcanoes include Mount Fuji in Japan, Mount Shasta and Mount Lassen in California, Mount St. Helens and Mount Rainier in
Washington State, Mount Hood in Oregon, and Mount Etna in Italy.
Composite volcanoes will rise as much as 8,000 feet above their base. Most composite volcanoes have a crater at the summit, which contains a central vent or a clustered group of vents.Most volcanoes on Earth are of this type. Stratovolcanoes kill more people than any other type of volcanoes - this is because of their abundance on Earth and their powerful mudflows.
Composite volcanoes often form the largest and tallest volcanoes. They are the most explosive and dangerous of the types of volcanoes.
Most of the tall volcanoes, like Mount St. Helens and Mount Rainier in Washington and Mount Fuji in Japan are composite volcanoes. These volcanoes usually have a big explosion when they erupt, and in-between eruptions you might not even be able to tell they are volcanoes, because they are very quiet and look just like other
mountains.
Shape is largely a function of slope angle; at the one
extreme are very shallow slopes that characterize shields, and on the other are the steeper slopes that characterize cones and domes. Among the smaller edifices are cinder cones and domes, which are typically monogenetic (formed from a single eruption episode).
Compared with caldera systems, composite volcanoes erupt smaller volumes more frequently and less explosively, which likely inhibits the long-term extreme differentiation, which typifies caldera-forming magmas.Young stratovolcanoes are typically steep sided and symmetrically cone shaped. There are several active stratovolcanoes in North America. Since 1980 Mount Saint Helens in Washington has become the most familiar.dimension built of alternating layers of lava flow, volcanic ash and cinders.
Famous composite volcanoes include Mount Fuji in Japan, Mount Shasta and Mount Lassen in California, Mount St. Helens and Mount Rainier in
Washington State, Mount Hood in Oregon, and Mount Etna in Italy.
Composite volcanoes will rise as much as 8,000 feet above their base. Most composite volcanoes have a crater at the summit, which contains a central vent or a clustered group of vents.Most volcanoes on Earth are of this type. Stratovolcanoes kill more people than any other type of volcanoes - this is because of their abundance on Earth and their powerful mudflows.
Wednesday, March 23, 2011
Active volcanoes
Active volcanoes are those that are currently erupting or showing signs of unrest, such as unusual earthquake activity or significant new gas emissions.Regularly active volcano ejected lava, ash, smoke and other substances. With a very active volcano this happens almost constantly. In the other between the eruption extended weeks or months.
While there is evidence of volcanic activity in the past, a lot of volcanoes are active today. They’re bubbling with lava, spewing ash and triggering earthquakes as you sit in class.Explosive eruptions can shoot columns of gases and rock fragments tens of miles into the atmosphere, spreading ash hundreds of miles downwind.
While some of the volcanoes are dormant for hundreds of years, others who were believed to be extinct, become active again, as happened 1973rd with Helgafelom (Hajmej, Iceland).
Alaska is home to 41 historically active volcanoes stretching across the entire southern portion of the State from the Wrangell Mountains to the far Western Aleutians. An average of 1-2 eruptions per year occur in Alaska.
Mount Etna, the largest active volcano in Europe, reaching 3,350 m and covering a surface of about 1,260 km2, started its activity at about 600 ka, after the end of Upper Pliocene to Pleistocene subaqueous and subaerial eruptions at the northwestern edge of the Iblean Plateau. Mt.
The New Zealand area is characterised by both a high density of active volcanoes and a high frequency of eruptions.
The largest volcanic eruption of the 20th century occurred at Novarupta Volcano in June 1912. It started by generating an ash cloud that grew to thousands of miles wide during the three-day event.
Some volcanoes expel gas and burning lava in the terrifying outbursts. Others have explosive eruptions and expel clouds of ash and gas.Volcanoes are evidence that the Earth is restless, especially within the crust and upper mantle.
If you live near an active or dormant volcano, you should be prepared to evacuate at a moment’s notice, as eruptions are not always predictable.Volcanoes can be incredibly destructive to buildings and dangerous to your family. In addition to the direct hazards, an eruption can be accompanied by landslides, mudflows, flash floods, earthquakes and tsunamis.
While there is evidence of volcanic activity in the past, a lot of volcanoes are active today. They’re bubbling with lava, spewing ash and triggering earthquakes as you sit in class.Explosive eruptions can shoot columns of gases and rock fragments tens of miles into the atmosphere, spreading ash hundreds of miles downwind.
While some of the volcanoes are dormant for hundreds of years, others who were believed to be extinct, become active again, as happened 1973rd with Helgafelom (Hajmej, Iceland).
Alaska is home to 41 historically active volcanoes stretching across the entire southern portion of the State from the Wrangell Mountains to the far Western Aleutians. An average of 1-2 eruptions per year occur in Alaska.
Mount Etna, the largest active volcano in Europe, reaching 3,350 m and covering a surface of about 1,260 km2, started its activity at about 600 ka, after the end of Upper Pliocene to Pleistocene subaqueous and subaerial eruptions at the northwestern edge of the Iblean Plateau. Mt.
The New Zealand area is characterised by both a high density of active volcanoes and a high frequency of eruptions.
The largest volcanic eruption of the 20th century occurred at Novarupta Volcano in June 1912. It started by generating an ash cloud that grew to thousands of miles wide during the three-day event.
Some volcanoes expel gas and burning lava in the terrifying outbursts. Others have explosive eruptions and expel clouds of ash and gas.Volcanoes are evidence that the Earth is restless, especially within the crust and upper mantle.
If you live near an active or dormant volcano, you should be prepared to evacuate at a moment’s notice, as eruptions are not always predictable.Volcanoes can be incredibly destructive to buildings and dangerous to your family. In addition to the direct hazards, an eruption can be accompanied by landslides, mudflows, flash floods, earthquakes and tsunamis.
Tuesday, March 22, 2011
Atacama desert facts
Facts about the Atacama are very interesting. The Atacama Desert is between the central Andes and Pacific Ocean in northern Chile. Located in northern Chile and extreme southern Peru, the Atacama Desert is located is perhaps the most unique physiographic location on earth. The Atacama Desert is also known as the Sechura Desert.
It is driest desert in the world. The Atacama Desert lies between two mountain ranges on the west coast of South America, the Coastal Cordillera and the Andean Cordillera. The Coastal Cordillera ranges in elevation from 500 to 3000 meters, and the Andean Cordillera ranges in elevation from 5000 to 6000 meters.Unlike other deserts, such as the Sahara in Africa and the Mojave in California, the Atacama is actually a very cool place with an average daily temperature between 0 ° C and 25 ° C.
Although it seems difficult that there is life in the Atacama, the holes are isolated and small areas of plants that provide a life of some insects and animals. Some plants are very well adapted to this arid environment, the development of long roots that reach to the water below the ground.Since the Andes mountain ranges active volcano, magma pressure of underground water in certain places causing geysers.
The Atacama Desert is probably the oldest desert on earth and has experienced extreme hyperaridity for at least 3 million years and probably 15 million years.The climate of the Atacama Desert is largely controlled by its zonal location between 15° and 30°S in the sub-tropical high-pressure belt where descending stable air produced by the Hadley circulation significantly reduces convection and hence precipitation.
Special attractions are the huge salt lake “Salar de Atacama”, which is almost dried out, and the bizarre landscape formations like the “Valley of the Moon” or the hot springs “Tatio Geysers”.
It is driest desert in the world. The Atacama Desert lies between two mountain ranges on the west coast of South America, the Coastal Cordillera and the Andean Cordillera. The Coastal Cordillera ranges in elevation from 500 to 3000 meters, and the Andean Cordillera ranges in elevation from 5000 to 6000 meters.Unlike other deserts, such as the Sahara in Africa and the Mojave in California, the Atacama is actually a very cool place with an average daily temperature between 0 ° C and 25 ° C.
Although it seems difficult that there is life in the Atacama, the holes are isolated and small areas of plants that provide a life of some insects and animals. Some plants are very well adapted to this arid environment, the development of long roots that reach to the water below the ground.Since the Andes mountain ranges active volcano, magma pressure of underground water in certain places causing geysers.
The Atacama Desert is probably the oldest desert on earth and has experienced extreme hyperaridity for at least 3 million years and probably 15 million years.The climate of the Atacama Desert is largely controlled by its zonal location between 15° and 30°S in the sub-tropical high-pressure belt where descending stable air produced by the Hadley circulation significantly reduces convection and hence precipitation.
Special attractions are the huge salt lake “Salar de Atacama”, which is almost dried out, and the bizarre landscape formations like the “Valley of the Moon” or the hot springs “Tatio Geysers”.
Monday, March 21, 2011
Yellowstone supervolcano
Yellowstone is the largest supervolcano on Earth!Most volcanoes that produce super-eruptions are very long-lived (active over millions of years), produce very large explosive eruptions, and remain dormant for long periods (from thousands to hundreds of thousands of years) between major eruptions.The Yellowstone supervolcano last erupted approximately 630,000 years ago. Scientists believe that it’s now overdue a repeat performance….
Beneath the beauty of America’s first national park is a killer volcano that is 1,000 times more powerful than Mt. Saint Helens and hundreds of times more powerful than all the volcanos in Iceland …combined! Yellowstone was set aside to protect and preserve its treasure of geothermal features—over 10,000 of them! Geysers are the most famous of these features— half of the world’s 700 geysers are located in Yellowstone.Three giant calderas in the western US, all formed in the last 1 million years include the Yellowstone hot-spot and two rift related supervolcanoes, Long valley caldera in eastern California and Valles caldera along the edge of the Rio Grande river in New Mexico.Each covered large areas of the US with volcanic ash when they last erupted.Although giant calderas (“supervolcanoes”) may slumber for tens of thousands of years between eruptions, their abundant earthquakes and crustal deformation reveal the potential for future upheaval.The super volcano at Yellowstone, and its kin around the world are a credible threat to man.“Yellowstone supervolcano could erupt again and when it does the whole world will be transformed.Yellowstone is located in the Rocky Mountain chain, but its geological story is different.At Yellowstone, the large thermal and CO2 fluxes require massive input of basaltic magma, which continues to invade the lower to mid-crust, sustains the overlying high-silica magma reservoir, and may result in volcanic hazard for millennia to come.
Beneath the beauty of America’s first national park is a killer volcano that is 1,000 times more powerful than Mt. Saint Helens and hundreds of times more powerful than all the volcanos in Iceland …combined! Yellowstone was set aside to protect and preserve its treasure of geothermal features—over 10,000 of them! Geysers are the most famous of these features— half of the world’s 700 geysers are located in Yellowstone.Three giant calderas in the western US, all formed in the last 1 million years include the Yellowstone hot-spot and two rift related supervolcanoes, Long valley caldera in eastern California and Valles caldera along the edge of the Rio Grande river in New Mexico.Each covered large areas of the US with volcanic ash when they last erupted.Although giant calderas (“supervolcanoes”) may slumber for tens of thousands of years between eruptions, their abundant earthquakes and crustal deformation reveal the potential for future upheaval.The super volcano at Yellowstone, and its kin around the world are a credible threat to man.“Yellowstone supervolcano could erupt again and when it does the whole world will be transformed.Yellowstone is located in the Rocky Mountain chain, but its geological story is different.At Yellowstone, the large thermal and CO2 fluxes require massive input of basaltic magma, which continues to invade the lower to mid-crust, sustains the overlying high-silica magma reservoir, and may result in volcanic hazard for millennia to come.
Sunday, March 20, 2011
Super volcano eruptions
In the past, several super vulcano eruptions sufficiently large to cause a global disaster have occurred, on average, every 100,000 years.Most volcanoes that produce super-eruptions are very long-lived (active over millions of years), produce very large explosive eruptions, and remain dormant for long periods (from thousands to hundreds of thousands of years) between major eruptions.The appearance of the volcano itself after eruption is also distinctive: it doesn’t conform to the common image of a volcano as a lofty, symmetrical, conical structure.The power of a volcano is measured by how much magma and ash it produces. A supervolcano is the biggest, most destructive volcano.Supereruptions require a very large volume of magma with strong explosive potential. Explosive potential results from a high content of volatile constituents (mostly H2O) that can form gas bubbles, combined with high viscosity to inhibit escape of the bubbles from the magma; it is the bursting of these trapped bubbles that drives an explosion. Supereruptions are “the ultimate geologic hazard,” in terms of the immediate and devastating impact of eruption products on our social infrastructure, and with regard to the longer-term climatic effects that will arise from loading the stratosphere with sulfur-rich gases.A supervolcano eruption packs the devastating force of a small asteroid colliding with the earth and occurs 10 times more often—making such an explosion one of the most dramatic natural catastrophes humanity should expect to undergo.Yellowstone is the largest super volcano on Earth!Beneath the beauty of America’s first national park is a killer volcano that is 1,000 times more powerful than Mt. Saint Helens and hundreds of times more powerful than all the volcanos in Iceland …combined!
How volcanoes erupt
Many of us are interested in how volcanoes erupt.
Many large volcanoes on Earth are capable of explosive eruptions much bigger than any experienced by humanity over historic time.Unlike other mountains, which are pushed up from below, volcanoes are built by surface accumulation of their eruptive products—layers of lava flows, ash flows, and ash. When pressure from gases within the molten rock becomes too great, gases drive the molten rock to the surface and an eruption occurs.This is how volcanoes erupt.
The molten rock that comes out of a volcano has been brought to the surface by a combination of things. The main one is the force of gravity: the molten rock is not as dense as the rocks around it so it tries to go upwards, just as the heated wax in a lava lamp will rise.
The gases dissolved in it are also one thing that helps it erupt (like carbon dioxide and sulphur dioxide), which come out as bubbles as the pressure reduces when it nears the surface and can force it out explosively, a bit like when you shake up a Coke bottle and take the top off: the gas forces out the Coke in a fountain.
Most gases from a volcano quickly blow away. However, heavy gases such as carbon dioxide and hydrogen sulfide can collect in low-lying areas.Although gases usually blow away rapidly, it is possible that people who are close to the volcano or who are in the low-lying areas downwind may be exposed to levels that may affect health.At depth in the Earth nearly all magmas contain gas dissolved in the liquid, but the gas forms a separate vapor phase when pressure is decreased as magma rises toward the surface of the Earth.In 1984, CO2 gas escaping from the bottom of Lake Monoun, a crater lake in the African country of Cameroon, killed 37 people.In 1986 an even larger CO2 gas emission from Lake Nyos in Cameroon killed more than 1700 people and 3000 cattle.Clouds of gas and tephra that rise above a volcano produce an eruption column that can rise up to 45 km into the atmosphere. Eventually the tephra in the eruption column will be picked up by the wind, carried for some distance, and then fall back to the surface as a tephra fall or ash fall.
Many large volcanoes on Earth are capable of explosive eruptions much bigger than any experienced by humanity over historic time.Unlike other mountains, which are pushed up from below, volcanoes are built by surface accumulation of their eruptive products—layers of lava flows, ash flows, and ash. When pressure from gases within the molten rock becomes too great, gases drive the molten rock to the surface and an eruption occurs.This is how volcanoes erupt.
The molten rock that comes out of a volcano has been brought to the surface by a combination of things. The main one is the force of gravity: the molten rock is not as dense as the rocks around it so it tries to go upwards, just as the heated wax in a lava lamp will rise.
The gases dissolved in it are also one thing that helps it erupt (like carbon dioxide and sulphur dioxide), which come out as bubbles as the pressure reduces when it nears the surface and can force it out explosively, a bit like when you shake up a Coke bottle and take the top off: the gas forces out the Coke in a fountain.
Most gases from a volcano quickly blow away. However, heavy gases such as carbon dioxide and hydrogen sulfide can collect in low-lying areas.Although gases usually blow away rapidly, it is possible that people who are close to the volcano or who are in the low-lying areas downwind may be exposed to levels that may affect health.At depth in the Earth nearly all magmas contain gas dissolved in the liquid, but the gas forms a separate vapor phase when pressure is decreased as magma rises toward the surface of the Earth.In 1984, CO2 gas escaping from the bottom of Lake Monoun, a crater lake in the African country of Cameroon, killed 37 people.In 1986 an even larger CO2 gas emission from Lake Nyos in Cameroon killed more than 1700 people and 3000 cattle.Clouds of gas and tephra that rise above a volcano produce an eruption column that can rise up to 45 km into the atmosphere. Eventually the tephra in the eruption column will be picked up by the wind, carried for some distance, and then fall back to the surface as a tephra fall or ash fall.
Saturday, March 19, 2011
Earthquake location
There are several methods used to locate earthquakes, triangulation is one that uses distance information from 3 or more stations to uniquely locate an earthquake.For an earthquake at the surface there are three unknowns: latitude, longitude, origin time.Triangulation is a method that uses distance information determined from 3 seismic stations to uniquely locate the earthquake.
An earthquake location specifies the place and time of occurrence of energy release from a seismic event.The location may refer to the earthquake's epicentre, hypocentre, or centroid, or to another observed or calculated property of the earthquake that can be spatially and temporally localized.An earthquake epicenter can be located from records made of earthquake waves on devices called seismographs.
A location is called absolute if it is determined or specified within a fixed, geographic coordinate system and a fixed time base, a location is called relative if it is determined or specified with respect to another spatio-temporal object which may have unknown or uncertain absolute location.We can locate earthquakes using a simple fact: an earthquake creates different seismic waves (P waves, S waves, etc.) The different waves each travel at different speeds and therefore arrive at a seismic station at different times.
For rapid hazard assessment and emergency response, an earthquake location provides information such as the locality of potential damage or the source region of a possible tsunami, and a location is required to calculate most measures of the size of an earthquake, such as magnitude or moment.
Since earthquakes occur deep in the Earth, their source locations must be inferred indirectly from distant observations, and earthquake location is thus a remote-sensing problem.
An earthquake location specifies the place and time of occurrence of energy release from a seismic event.The location may refer to the earthquake's epicentre, hypocentre, or centroid, or to another observed or calculated property of the earthquake that can be spatially and temporally localized.An earthquake epicenter can be located from records made of earthquake waves on devices called seismographs.
A location is called absolute if it is determined or specified within a fixed, geographic coordinate system and a fixed time base, a location is called relative if it is determined or specified with respect to another spatio-temporal object which may have unknown or uncertain absolute location.We can locate earthquakes using a simple fact: an earthquake creates different seismic waves (P waves, S waves, etc.) The different waves each travel at different speeds and therefore arrive at a seismic station at different times.
For rapid hazard assessment and emergency response, an earthquake location provides information such as the locality of potential damage or the source region of a possible tsunami, and a location is required to calculate most measures of the size of an earthquake, such as magnitude or moment.
Since earthquakes occur deep in the Earth, their source locations must be inferred indirectly from distant observations, and earthquake location is thus a remote-sensing problem.
Wednesday, March 16, 2011
Earthquakes causes and effects
Here, i have tried to explain the nature, distribution, causes and effects of this terrifying natural event.A large number of earthquakes are felt all over the globe every year.Most human lives in earthquakes are lost due to collapse of houses. Styles of making houses depend on local climate, construction material available and on local traditions. The small ones are unnoticed while the large ones are felt over thousands of kilometers.When the earthquake struck, the longer, more flexible columns at the front of the building passed the earthquake forces on to the short, stiffer columns in the back instead of distributing the forces equally among all of the columns.Many properly executed buildings are not safe against earthquakes, simply because their foundations were made without considering the earthquake hazard.When an earthquake occurs in a populated area, it may cause deaths and injuries and extensive property damage.
Different types of seismic waves produce the violent ground shaking, or motion, associated with earthquakes.These wave vibrations produce several different effects on the natural environment that also can cause tremendous damage to the built environment (buildings, transportation lines and structures, communications lines, and utilities).Ground shaking from earthquakes can collapse buildings and bridges; disrupt gas, electric, and telephone service; and sometimes trigger landslides, avalanches, flash floods, fires, and huge, destructive, seismic sea waves called tsunamis.
Tsunami (“Soo na me”) is Japanese for tidal wave. A tsunami is caused by an earthquake, landslide, or volcanic eruption on the sea floor. Tsunamis are often no taller than normal wind waves, but they are much more dangerous.Tsunamis run quickly over the land as a wall of water.
Different types of seismic waves produce the violent ground shaking, or motion, associated with earthquakes.These wave vibrations produce several different effects on the natural environment that also can cause tremendous damage to the built environment (buildings, transportation lines and structures, communications lines, and utilities).Ground shaking from earthquakes can collapse buildings and bridges; disrupt gas, electric, and telephone service; and sometimes trigger landslides, avalanches, flash floods, fires, and huge, destructive, seismic sea waves called tsunamis.
Tsunami (“Soo na me”) is Japanese for tidal wave. A tsunami is caused by an earthquake, landslide, or volcanic eruption on the sea floor. Tsunamis are often no taller than normal wind waves, but they are much more dangerous.Tsunamis run quickly over the land as a wall of water.
Friday, March 11, 2011
Moon closest to earth
Moon closest to Earth since 1992nd.
19th March this year, the moon will be closest to Earth at a distance of only 356 577 km, What is the closest distance since 1992. The event, which is known as the lunar perigee will provide a unique opportunity for fantastic photos, but some scientists warn that it could disrupt the Earth's climate and cause earthquakes and volcanic activity.
Previous such events were associated with extreme weather, so in 2005. the tsunami killed hundreds of thousands of people, and 1974th the cyclone has devastated Australia.The Earth is thus closer to the moon 1955th, 1974., 1992. and 2005. year, all of which are marked by extreme storms. Before six years before the tsunami in Indonesia has killed hundreds of thousands of people, and 1974th The Cyclone Tracy devastated Australia.
Speculation of some scientists that this moon approaching could cause earthquakes and volcanic activity it may be true.For all the natural disasters are associated with some events in the night sky - a comet, planet, sun or moon.
While others do not agree with it and say:There will be no earthquakes or volcanic eruptions that would not be possible and otherwise.The Earth will experience only minor changes to low tide and larger changes in the tide, but it is nothing about which to be excited.The gravity of the moon is tugging on the Earth and causing a slight sort of distortion as the moon orbits the Earth and that leads to tides eventually.
19th March this year, the moon will be closest to Earth at a distance of only 356 577 km, What is the closest distance since 1992. The event, which is known as the lunar perigee will provide a unique opportunity for fantastic photos, but some scientists warn that it could disrupt the Earth's climate and cause earthquakes and volcanic activity.
Previous such events were associated with extreme weather, so in 2005. the tsunami killed hundreds of thousands of people, and 1974th the cyclone has devastated Australia.The Earth is thus closer to the moon 1955th, 1974., 1992. and 2005. year, all of which are marked by extreme storms. Before six years before the tsunami in Indonesia has killed hundreds of thousands of people, and 1974th The Cyclone Tracy devastated Australia.
Speculation of some scientists that this moon approaching could cause earthquakes and volcanic activity it may be true.For all the natural disasters are associated with some events in the night sky - a comet, planet, sun or moon.
While others do not agree with it and say:There will be no earthquakes or volcanic eruptions that would not be possible and otherwise.The Earth will experience only minor changes to low tide and larger changes in the tide, but it is nothing about which to be excited.The gravity of the moon is tugging on the Earth and causing a slight sort of distortion as the moon orbits the Earth and that leads to tides eventually.
Monday, March 7, 2011
Mariana trench depth
The Mariana trench has a maximum depth of 10,971 m (35,994 feet) below sea level, called Challenger Deep. It is located east of the Mariana Islands at 11°21`N, 142°12`E, near Guam. Mariana Trench was discovered in 1872. First they reached the Swiss Jacques Piccard and Don Walsh from America in 1960. Mariana Trench was formed at the point where it meets the bottom of the Pacific and Philippine tectonic plates. Its deepest parts are formed before 6-9 000 000 years. Mariana Trench is 23% deeper than it is Mount Everest high.
Mariana Trench is not only the deepest point of the Pacific Ocean, but the deepest point in the world. Data on its depth constantly vary, but the last say as its depth 12 111 feet below sea level.
At the bottom of the Mariana trench pressure is more than a thousand times greater than standard atmospheric pressure at sea level. However, that living beings can adapt to such pressures, Japanese scientists have proven that at 11 km depth reveal the microscopic organisms.
The origin of this huge underwater Valley is the result of movement of lithosphere plate.
Microscopic single-celled organisms, including many unknown, were discovered in the deepest parts of the Pacific Ocean at 10 896 feet deep, according to Japanese scientists. These organisms are found in the piece sinks of sediment from the Challenger southwest of the island of Guam, Mariana Trench in the Pacific. These organisms probably can survive by absorbing particulate organic matter dropped from the surface or substance that is dissolved in salt water.
Deep trenches, such as the Japan Trench, the Izu-Ogasawara Trench, the Mariana Trench, the Yap Trench, the Palau Trench, the Philippine Trench, and the Nansei- Shoto (Ryukyu) Trench are present in the western North Pacific Ocean.
Mariana Trench is not only the deepest point of the Pacific Ocean, but the deepest point in the world. Data on its depth constantly vary, but the last say as its depth 12 111 feet below sea level.
At the bottom of the Mariana trench pressure is more than a thousand times greater than standard atmospheric pressure at sea level. However, that living beings can adapt to such pressures, Japanese scientists have proven that at 11 km depth reveal the microscopic organisms.
The origin of this huge underwater Valley is the result of movement of lithosphere plate.
Microscopic single-celled organisms, including many unknown, were discovered in the deepest parts of the Pacific Ocean at 10 896 feet deep, according to Japanese scientists. These organisms are found in the piece sinks of sediment from the Challenger southwest of the island of Guam, Mariana Trench in the Pacific. These organisms probably can survive by absorbing particulate organic matter dropped from the surface or substance that is dissolved in salt water.
Deep trenches, such as the Japan Trench, the Izu-Ogasawara Trench, the Mariana Trench, the Yap Trench, the Palau Trench, the Philippine Trench, and the Nansei- Shoto (Ryukyu) Trench are present in the western North Pacific Ocean.
Saturday, March 5, 2011
Mesosphere facts
Here ar some interesting facts about mesosphere.The mesosphere cools with increasing height until it reaches the mesopause or minima with summer temperature at about −130 °C or lower, then it starts to warm again with height in the lower thermosphere. The mesosphere extends from between 31 and 50 miles (50 to 80 kilometers) above the earth's surface. The mesosphere is characterized by temperatures that quickly decrease as height increases with temperatures as low as -93°C at the top of the layer. Only rockets and meteors travel through this layer.And this is where meteors usually burn up when they enter Earth’s atmosphere.The mesosphere is the coldest layer of the atmosphere, where the thin air is often turbulent and strong gusty winds blow—it even contains ice aerosol clouds in summer.The boundary between the stratosphere and the mesosphere is known as the stratopause.The percentage of Nitrogen and Oxygen is about the same in the mesosphere as it is at sea level but the atmospheric pressure is much lower. The lapse rate in the mesosphere is approximately 2°C/1000 m.The mesopause marks the boundary between the mesosphere and the thermosphere.Due to reactions taking place in the thermosphere and upper mesosphere, mesospheric air is enhanced in reactive nitrogen compounds, which can effect ozone. Furthermore, mesospheric
air is enhanced in CO and is expected to show enhanced levels of molecular hydrogen and depleted values of water vapour, which may influence the chemistry of OH radicals.Long-period oscillations in the period range between 2-30 days, interpreted as planetary wave (PW) signatures, have been analysed using daily upper mesosphere/lower thermosphere wind measurements near 90 km over Collm (52°N, 15°E) in the time interval 1980-2005. Strong interannual and interdecadal variability of PW are found.
air is enhanced in CO and is expected to show enhanced levels of molecular hydrogen and depleted values of water vapour, which may influence the chemistry of OH radicals.Long-period oscillations in the period range between 2-30 days, interpreted as planetary wave (PW) signatures, have been analysed using daily upper mesosphere/lower thermosphere wind measurements near 90 km over Collm (52°N, 15°E) in the time interval 1980-2005. Strong interannual and interdecadal variability of PW are found.
Lahars
Lahars are rapidly flowing mixtures of rock debris and water that originate on the slopes of a volcano.Explosive eruptions can deposit huge amounts ash and other volcanic debris on a volcano’s slopes. Lahars form when water from intense rainfall, melting snow and ice, or the sudden failure of a natural dam, mixes with this loose volcanic material, creating mudflows that can be particularly dangerous and destructive.Volcanic eruptions may directly trigger one or more lahars by quickly melting snow and ice on a volcano or ejecting water from a crater lake.Although lahars contain at least 40% (by weight) volcanic ash and rock fragments—making them dense and viscous like wet concrete—they actually flow faster than clear-water streams.
As it rushes downstream, its size, speed, and the amount of water and rock debris it carries are constantly changing.Lahars can fall under three categories of classification, syn-eruptive, post-eruptive or
non-eruptive.Primary (syneruptive) lahars can occur when an eruptions
melts ice or a crater lake is breached.Secondary lahars can result
from debris avalanches (landslides) or from erosion of fresh, unconsolidated pyroclastic material.
Lahars Deposits
Because of bed friction, bottom layers move more slowly
-Consequently, larger particles work toward the front and margins
- Lower concentration flows can be normally graded as coarse material settles first
- Inverse grading is a consequence of “kinetic sieving”
Lahars have been the cause of major damage and loss of life throughout history. They have buried entire towns, and destroyed cities beyond repair.Their extreme danger makes them an important topic of research throughout the geosciences in the hopes of mitigating future disaster.
Lahars have the strength to rip huge boulders, trees, and man-made
structures from the ground, carrying them for great distances.
As it rushes downstream, its size, speed, and the amount of water and rock debris it carries are constantly changing.Lahars can fall under three categories of classification, syn-eruptive, post-eruptive or
non-eruptive.Primary (syneruptive) lahars can occur when an eruptions
melts ice or a crater lake is breached.Secondary lahars can result
from debris avalanches (landslides) or from erosion of fresh, unconsolidated pyroclastic material.
Lahars Deposits
Because of bed friction, bottom layers move more slowly
-Consequently, larger particles work toward the front and margins
- Lower concentration flows can be normally graded as coarse material settles first
- Inverse grading is a consequence of “kinetic sieving”
Lahars have been the cause of major damage and loss of life throughout history. They have buried entire towns, and destroyed cities beyond repair.Their extreme danger makes them an important topic of research throughout the geosciences in the hopes of mitigating future disaster.
Lahars have the strength to rip huge boulders, trees, and man-made
structures from the ground, carrying them for great distances.
Thursday, March 3, 2011
Unsafe building
Buildings with foundations resting on unconsolidated landfill and other unstable soils are at increased risk of damage.When an earthquake occurs in a populated area, it may cause deaths and injuries and extensive property damage.Entry into damaged unsafe buildings as soon as possible is often necessary for a variety of emergency reasons, including search and rescue, building stabilization and repair, and salvage and retrieval of possessions.We must all work together in our communities to apply our knowledge to enact and enforce up-to-date building codes, retrofit older unsafe buildings, and avoid building in hazardous areas, such as those prone to landslides.
For buildings considered stable, wait times depend on the main shock magnitude and the duration of occupancy, as both of these factors affect the probability of a large aftershock occurring during the period of occupancy.Because the aftershock hazard diminishes with time, it is possible to determine in general when the risk of entering
an UNSAFE building, for a given period of time, reaches an acceptable level.Cold-formed steel has become a popular building material for commercial and industrial buildings.Slices of cold-formed steel, which is normally used for braiding low and medium high-rise buildings, are made by bending sheet metal approximately one millimeter thick, without heating, the structural forms. These components are usually easier and cheaper than traditional construction systems and have other advantages. For example, pieces of cold-formed steel are more homogeneous than the wooden components and does not possess the sensitivity of the termite and wood rot.Structural engineers who designed the building from cold-formed steel should provide more data on how the material will behave during an earthquake.
We must also look for and eliminate hazards at home, where our children
spend their days, and where we work. And we must learn and practice what to do if an earthquake occurs.
For buildings considered stable, wait times depend on the main shock magnitude and the duration of occupancy, as both of these factors affect the probability of a large aftershock occurring during the period of occupancy.Because the aftershock hazard diminishes with time, it is possible to determine in general when the risk of entering
an UNSAFE building, for a given period of time, reaches an acceptable level.Cold-formed steel has become a popular building material for commercial and industrial buildings.Slices of cold-formed steel, which is normally used for braiding low and medium high-rise buildings, are made by bending sheet metal approximately one millimeter thick, without heating, the structural forms. These components are usually easier and cheaper than traditional construction systems and have other advantages. For example, pieces of cold-formed steel are more homogeneous than the wooden components and does not possess the sensitivity of the termite and wood rot.Structural engineers who designed the building from cold-formed steel should provide more data on how the material will behave during an earthquake.
We must also look for and eliminate hazards at home, where our children
spend their days, and where we work. And we must learn and practice what to do if an earthquake occurs.
Tuesday, March 1, 2011
Ground shaking
Ground shaking from earthquakes can collapse buildings and bridges, disrupt gas, electric, and telephone service, and sometimes trigger landslides, avalanches, flash floods, fires, and huge, destructive, seismic sea waves called tsunamis.
An earthquake is a sudden movement of the Earth caused by the abrupt release of energy that has accumulated over a long time.
Objective is to estimate the ground shaking from a specified earthquake, sometimes called a scenario earthquake.In seismic design, characteristics of the maximum ground shaking are desired.
For hundreds of millions of years, the forces of plate tectonics have shaped the earth as the huge plates that form the surface move slowly over, under, past, and away from each other.
The ground shakes or vibrates as the seismic waves cause small temporary displacements of the ground.At the surface, the ground moves vertically up and down and horizontally back and forth.The strength and frequency of seismic waves and the length of time strong shaking lasts all affect the amount of damage caused by ground shaking.
When an earthquake occurs in a populated area, it may cause deaths and injuries and extensive property damage. Buildings with foundations resting on unconsolidated landfill and other unstable soils are at increased risk of damage. The effects of earthquake ground shaking depend on the specific response characteristics of the type of structural system used.
Ground shaking may also trigger soil liquefaction, landslides, and other types of ground failure, which can also cause damage.
Initial effects of an earthquake are violent ground motions which can produce cracks or fractures in the ground and liquefaction, where loose sandy soils with a high moisture content separate and give the surface a consistency much like that of quicksand.
An earthquake is a sudden movement of the Earth caused by the abrupt release of energy that has accumulated over a long time.
Objective is to estimate the ground shaking from a specified earthquake, sometimes called a scenario earthquake.In seismic design, characteristics of the maximum ground shaking are desired.
For hundreds of millions of years, the forces of plate tectonics have shaped the earth as the huge plates that form the surface move slowly over, under, past, and away from each other.
The ground shakes or vibrates as the seismic waves cause small temporary displacements of the ground.At the surface, the ground moves vertically up and down and horizontally back and forth.The strength and frequency of seismic waves and the length of time strong shaking lasts all affect the amount of damage caused by ground shaking.
When an earthquake occurs in a populated area, it may cause deaths and injuries and extensive property damage. Buildings with foundations resting on unconsolidated landfill and other unstable soils are at increased risk of damage. The effects of earthquake ground shaking depend on the specific response characteristics of the type of structural system used.
Ground shaking may also trigger soil liquefaction, landslides, and other types of ground failure, which can also cause damage.
Initial effects of an earthquake are violent ground motions which can produce cracks or fractures in the ground and liquefaction, where loose sandy soils with a high moisture content separate and give the surface a consistency much like that of quicksand.
Sunday, February 27, 2011
Earth crust displacement
Theory of the Earth crust displacement shows that over long periods of time, approximately forty one thousand years, certain forces act in the direction of the outer limits of endurance.Among the critical factors are: massive accumulation of ice at the poles, which changes the weight of the crust, the Earth's axis tilt, which is every 41 000 was changed for more than three degrees (which should not be confused with the volatility that causes the precession of the equinoxes), and, of course, relative proximity to massive celestial bodies like the Moon and the Sun, which also varies throughout the precessional cycle of several thousand years.The theory of Crustal Displacement states that the entire crust of the Earth can shift in one piece like the lose skin on an orange.The assumption is that the outer crust of the earth in relation to the cellular interior, but the tectonic plate movements, the movement is extremely slow.
Vertical displacements of the earth's crust along the rupture resulting from such earthquakes can generate destructive tsunami waves which can travel across an ocean spreading destruction across their path.
Tectonics actually talking about a series of plates that move very slowly in relation to each other.But when it comes to Earth crust displacement, all the plates as a single whole, part of the outer shell of the Earth, which moves in relation to the interior of the Earth.
Most earthquakes happen where tectonic plates meet and glide against each other. Quakes occur when the frictional stress of the movement exceeds the strength of the rocks, causing a failure at a fault line. Violent displacement of the Earth's crust follows, leading to a release of elastic strain energy.
The Crust is a thin layer of solid rock. The material that makes up the crust tends to be lighter than the materials below. The Earth’s crust “floats” on the inner layers. If the Earth were the size of a peach, the crust would only be as thick as the peach’s skin (and not as fuzzy). If the Earth hadn’t cooled enough for the crust to form on its surface, we wouldn’t be here. Neither would any living thing we know of.
Scientists have never been able to dig or drill down through the crust to the mantle. Driving 100 kilometers is easy. Drilling that far through solid rock is hard. Well, it’s solid rock. But, we can study the inside of the Earth by observing volcanoes and geysers. The heat that melts rock into magma, and turns underground water into steam, comes from under the crust.
Most of the evidence usually cited to support the idea of an ice age, there are better fits the theory of earth crust displacement.
Vertical displacements of the earth's crust along the rupture resulting from such earthquakes can generate destructive tsunami waves which can travel across an ocean spreading destruction across their path.
Tectonics actually talking about a series of plates that move very slowly in relation to each other.But when it comes to Earth crust displacement, all the plates as a single whole, part of the outer shell of the Earth, which moves in relation to the interior of the Earth.
Most earthquakes happen where tectonic plates meet and glide against each other. Quakes occur when the frictional stress of the movement exceeds the strength of the rocks, causing a failure at a fault line. Violent displacement of the Earth's crust follows, leading to a release of elastic strain energy.
The Crust is a thin layer of solid rock. The material that makes up the crust tends to be lighter than the materials below. The Earth’s crust “floats” on the inner layers. If the Earth were the size of a peach, the crust would only be as thick as the peach’s skin (and not as fuzzy). If the Earth hadn’t cooled enough for the crust to form on its surface, we wouldn’t be here. Neither would any living thing we know of.
Scientists have never been able to dig or drill down through the crust to the mantle. Driving 100 kilometers is easy. Drilling that far through solid rock is hard. Well, it’s solid rock. But, we can study the inside of the Earth by observing volcanoes and geysers. The heat that melts rock into magma, and turns underground water into steam, comes from under the crust.
Most of the evidence usually cited to support the idea of an ice age, there are better fits the theory of earth crust displacement.
Saturday, February 26, 2011
Traffic pollution causes
Pollution from traffic is for children a special concern because their immune system and lungs are not fully developed when exposure begins.Air pollution is mostly due to industry in developed countries.Automobile transport is now an inherent part of our civilisation, and as it happened with many other technological advancements, the negative aspects are becoming more andmore pronounced. Pollution intake is also determined by the number of people in polluted areas, how long they stay there and what they do. The growing use of old, poorly maintained passenger cars and the use of diesel fuel have dramatically worsened air quality.
The road traffic is known to be the major contributor to the anthropogenic emissions of the "greenhouse" gas Carbon Dioxide (CO2) and it is expected that these emissions willcontinue to increase with the steadily increasing amount of traffic.Carbon dioxide (CO2) is one of the major pollutants in the atmosphere. Major sources of CO2 are fossil fuels burning and deforestation.The most severe damaging effects related to pollution from traffic can, however, be found in urban areas. It is here that the traffic density is largest and concentrations of car exhaust gases are often orders of magnitude higher than in rural areas.Traffic exhaust gases contain pollutants such as nitrogen oxides [NOx defined as the sum of nitrogen monoxide (NO) and nitrogen dioxide (NO2)], hydrocarbons, carbon monoxide (CO), and particles.The largest pollution levels occur in street canyons where dilution of car exhaust gases is significantly limited by the presence of buildings flanking the street.In a 0.5-km-wide belt along major urban highways, concentrations of nitrogen dioxide, black smoke (or soot) and ultrafine particles are markedly higher than in areas with less traffic.
In order to design effective approaches to pollution management from mobile sources, it is important to diagnose urban air pollution problems, determine the impact of mobile sources, and identify affordable and sustainable solutions.
The effects on health of transport-related air pollution are among the leading concerns about transport.
Motor vehicles are being used too much, and they are not “clean” enough when they are used.
The road traffic is known to be the major contributor to the anthropogenic emissions of the "greenhouse" gas Carbon Dioxide (CO2) and it is expected that these emissions willcontinue to increase with the steadily increasing amount of traffic.Carbon dioxide (CO2) is one of the major pollutants in the atmosphere. Major sources of CO2 are fossil fuels burning and deforestation.The most severe damaging effects related to pollution from traffic can, however, be found in urban areas. It is here that the traffic density is largest and concentrations of car exhaust gases are often orders of magnitude higher than in rural areas.Traffic exhaust gases contain pollutants such as nitrogen oxides [NOx defined as the sum of nitrogen monoxide (NO) and nitrogen dioxide (NO2)], hydrocarbons, carbon monoxide (CO), and particles.The largest pollution levels occur in street canyons where dilution of car exhaust gases is significantly limited by the presence of buildings flanking the street.In a 0.5-km-wide belt along major urban highways, concentrations of nitrogen dioxide, black smoke (or soot) and ultrafine particles are markedly higher than in areas with less traffic.
In order to design effective approaches to pollution management from mobile sources, it is important to diagnose urban air pollution problems, determine the impact of mobile sources, and identify affordable and sustainable solutions.
The effects on health of transport-related air pollution are among the leading concerns about transport.
Motor vehicles are being used too much, and they are not “clean” enough when they are used.
Earth core facts
The first indication of Earth-core complexity came with Lehmann’s 1936 discovery of the inner core.The core is approximately half the radius of the Earth and is about twice as dense as the mantle. It represents 32 percent of the mass of the Earth. Iron crystals are the main constituents of the solid inner core.The actual presence of the solid inner core inside Earth was proven after the great Alaska earthquake of 28 March 1964 and is no longer questioned today. Estimating properties of this inner core, however, remains a major challenge.The crystals may have grown with a preferred orientation when the inner core was formed, or processes at work in the inner core may have aligned them over time.The dynamics of the core is critically influenced by the combined effects of rotation and magnetic fields.The core has some additional impurities; about 6% of Ni and about 10% of lighter elements such as H, O, S, and C. The light elements are believed to exist preferentially in the fluid outer core as compared with the solid inner core.Earth in its entirety can be considered a slow nuclear reactor with its solid ”inner core” providing a major contribution to the total energy output. Since radionic heat is generated in the entire volume and cooling can only occur at the surface, the highest temperature inside Earth occurs at the center of the inner core. Overheating the center of the inner core reactor due to the so-called greenhouse effect on the surface of Earth may cause a meltdown condition, an enrichment of nuclear fuel and a gigantic atomic explosion.In order to understand better the origin of the seismic anisotropy observed in the inner core, experiments and theories have focussed on the mechanical behavior of crystalline iron at the extreme conditions of the inner core estimated to have temperature of about
5000K and pressure of 330GPa.
The primary dynamics of the Earth’s fluid core is controlled by rapid rotation, small viscosity, thermal or compositional convection, and a self-generatedmagnetic field.
Several facts about the core, however, can be established directly from the seismic data with quite considerable ncertainty:
The ”inner core” (the part inside the 1220 km radius) is a solid, because it transmits shear waves and only a solid can do this.
The ”outer core” that surrounds the solid inner core appears to be a fluid - due to the absence of shear waves there.
To a seismologist, who performs observations with respect to the surface of Earth, the solid inner core seems slightly anisotropic, a few %, and this anisotropy seems "spinning" inside the planet about 4% faster than the planet spins around its own axis.
In contrast to the outer core, the inner core is denser than pure iron, so it is thought to be iron-nickel without a light element. Thus it is chemically different from the outer core, as well as being solid rather
than liquid.
5000K and pressure of 330GPa.
The primary dynamics of the Earth’s fluid core is controlled by rapid rotation, small viscosity, thermal or compositional convection, and a self-generatedmagnetic field.
Several facts about the core, however, can be established directly from the seismic data with quite considerable ncertainty:
The ”inner core” (the part inside the 1220 km radius) is a solid, because it transmits shear waves and only a solid can do this.
The ”outer core” that surrounds the solid inner core appears to be a fluid - due to the absence of shear waves there.
To a seismologist, who performs observations with respect to the surface of Earth, the solid inner core seems slightly anisotropic, a few %, and this anisotropy seems "spinning" inside the planet about 4% faster than the planet spins around its own axis.
In contrast to the outer core, the inner core is denser than pure iron, so it is thought to be iron-nickel without a light element. Thus it is chemically different from the outer core, as well as being solid rather
than liquid.
Thursday, February 24, 2011
Strong solar storms could shut down power on Earth
Earth due to heavy storms on the sun for a few months could remain without power, without the support of satellites, and air traffic would be able to stop, warn scientists. A strong eruption of energy caused by solar storms sent waves toward the Earth, which are used for aircraft navigation or communication for mobile.The problem of weather conditions in the universe should be taken seriously.Since we've become dependent on technologies that depend on the support of satellites, solar storms in future could be very dangerous.Strongest solar storm in the last four years was recorded on 14 February of this year.The sun has entered a new cycle of activity, whose peak is expected 2013th year.The last time we took the maximum of solar cycle, ten years ago, the world was a different place.We were less dependent on mobile phones than it is today.The sun passes through its active cycle approximately every 11 years. The last peak occurred in 2001. , and then it was pretty weak, but it lasted longer. A solar flare 1972nd was interrupted by the international phone lines in Illinois. A similar thing happened to 1989. , when the solar flare caused a "geomagnetic storm that disrupted electric power transmission" in the Canadian province of Quebec.
There are three known types of solar flares:
-X-class flares marked the strongest eruptions of the Sun,
-Class M (medium power, but still powerful),
-Class C, indicating the weakest type of solar storms.
There are three known types of solar flares:
-X-class flares marked the strongest eruptions of the Sun,
-Class M (medium power, but still powerful),
-Class C, indicating the weakest type of solar storms.
Monday, February 21, 2011
Poo-Gloo - igloo-shaped devices that eat waste
Inexpensive devices in the form of the igloo, which is literally food contamination, of a mile a mentioned Poo-Gloo can clean sewage as effective as treatment plants, waste worth several million dollars in cities that outgrew its lagoon waste water treatment, according to a new study.Treatment of wastewater in small, rural communities is an important and challenging task of engineers. Appropriate treatment includes disinfection and removal of unwanted contaminants.Most rural communities rely on the lagoon for collecting waste water as a primary method of treatment because they are simple and inexpensive to manage. Lagoons are actually a large pool in which the sewage holding from one month to one year to be deposited solids, and sunlight, bacteria, wind and other natural processes clean water, sometimes with the help of aeration.But as communities grow and cleaning of pollution is becoming weaker, more conventional lagoons to collect waste water can no longer provide adequate treatment.Poo-Gloo is designed to address the problems faced by companies that grow their own sewage lagoon. The device provides a great surface on which bacteria can grow, thus ensuring the microbial air and dark environment in order to continually consume pollutants from sewage with a minimum of rivalry algae.
Poo-Gloo-use and advanced bacterial biofilm to consume contaminants. Two dozen or more Poo-Gloo in the form of the igloo is placed at the bottom of the lagoon, submerged completely and arranged in rows.Each Poo-Gloo consists of sets of four plastic dome, which is progressively reduced and are one of the other like Russian 'babushka', and are filled with plastic containers to ensure a large surface area for bacterial growth. Seals on the pipes to drain the bubbles are located at the bottom of each Poo-Gloo and emit bubbles of air through the cavity between the domes. The air coming out of the hole at the top of the dome. As the air moves through the dome, also pushes water from the lagoon bottom to the top of the dome.Each Poo-Gloo occupies 2.6 square feet of space at the bottom of the lagoon, which makes 260 square meters of free space for the growth of bacteria. The combination of large surface area, aeration, continuous mixing and dark environment that limits the algal growth rate approaching destruction of contaminants in Poo-Gloo, the rate of mechanical plant.
Poo-Gloo-use and advanced bacterial biofilm to consume contaminants. Two dozen or more Poo-Gloo in the form of the igloo is placed at the bottom of the lagoon, submerged completely and arranged in rows.Each Poo-Gloo consists of sets of four plastic dome, which is progressively reduced and are one of the other like Russian 'babushka', and are filled with plastic containers to ensure a large surface area for bacterial growth. Seals on the pipes to drain the bubbles are located at the bottom of each Poo-Gloo and emit bubbles of air through the cavity between the domes. The air coming out of the hole at the top of the dome. As the air moves through the dome, also pushes water from the lagoon bottom to the top of the dome.Each Poo-Gloo occupies 2.6 square feet of space at the bottom of the lagoon, which makes 260 square meters of free space for the growth of bacteria. The combination of large surface area, aeration, continuous mixing and dark environment that limits the algal growth rate approaching destruction of contaminants in Poo-Gloo, the rate of mechanical plant.
Types of earthquake prediction
Types of earthquake prediction are:
-Earthquake forecast: statement on long-term statistical probability of earthquake in a certain area,
-Long-term prediction,
-Short-term prediction,
-Earthquake warning: actionable declaration, up to a few days
The notion that several different kinds of prediction might be possible, each with its own time scale, is central to current debates about earthquake prediction. A short-term prediction of a few days to weeks, based on some earthquake process with a short time scale (e.g., nucleation), is distinct from a long-term prediction based on a longer-term process (e.g., stress buildup due to plate motions). These different kinds of predictions may have very different chances for success.
Long term prediction
Long-term prediction is based mainly on the knowledge of when and where earthquakes have occurred in the past.The physical bases for this type of prediction are the slow buildup of stress, the loading rate for each fault segment, and the timing of the warning interval with respect to the approximate time remaining in the cycle of large earthquakes.Predictions of this type are usually probabilistic in nature to allow for observed differences in individual repeat times and uncertainties in the parameters used in the calculations.
Abundant evidence shows that earthquakes are unstable slip repeating on existing weak planes in the earth’s topmost part, which is too cold (<300C) to deform stably. An earthquake occurs when the stress on the weak plane, which increases slowly due to plate motion, reaches the frictional strength.Two methods of earthquake forecasting are being employed - paleoseismology and seismic gaps.
Paleoseismology - the study of prehistoric earthquakes. Through study of the offsets in sedimentary layers near fault zones, it is often possible to determine recurrence intervals of major earthquakes prior to historical records.
Seismic gaps - A seismic gap is a zone along a tectonically active area where no earthquakes have occurred recently, but it is known that elastic strain is building in the rocks. If a seismic gap can be identified, then it might be an area expected to have a large earthquake in the near future.
Short-term prediction
Based on the earthquake event itself.
The public perception in many countries and, in fact, that of many earth scientists is that earthquake prediction means short-term prediction, a warning of hours to days.They typically equate a successful prediction with one that is 100% reliable. If we want to predict a plate-boundary earthquake with, say, 1-year accuracy, we need to know the strength and the current stress level with an accuracy of 0.1MPa, which way we do not know. So, we hope that Mother Nature has something more in favor of us, which we call ‘earthquake
preparation processes.Anomalous events or processes that may precede an earthquake are called precursor events and might signal a coming earthquake.Despite the array of possible precursor events that are possible to monitor, successful short-term earthquake prediction has so far been difficult to obtain.The processes that cause earthquakes occur deep beneath the surface and are difficult to monitor.Earthquakes in different regions or along different faults all behave differently, thus no consistent patterns have so far been recognized.For many large earthquakes, foreshocks are either absent or of very small size, making them unreliable for prediction purposes. Hence, the question of whether short-term prediction is possible depends on whether or not a means can be devised to detect nucleation directly, and if the form of the nucleation is predictive of the size as well as the time and the place of the subsequent event.
A prediction is a neutral statement made based on accumulated observations.A warning is a declaration that normal life routines should be altered to deal with the impending hazard.
Prediction- based on science.
Warning- Interpretations of prediction that take public policy into account.
-Earthquake forecast: statement on long-term statistical probability of earthquake in a certain area,
-Long-term prediction,
-Short-term prediction,
-Earthquake warning: actionable declaration, up to a few days
The notion that several different kinds of prediction might be possible, each with its own time scale, is central to current debates about earthquake prediction. A short-term prediction of a few days to weeks, based on some earthquake process with a short time scale (e.g., nucleation), is distinct from a long-term prediction based on a longer-term process (e.g., stress buildup due to plate motions). These different kinds of predictions may have very different chances for success.
Long term prediction
Long-term prediction is based mainly on the knowledge of when and where earthquakes have occurred in the past.The physical bases for this type of prediction are the slow buildup of stress, the loading rate for each fault segment, and the timing of the warning interval with respect to the approximate time remaining in the cycle of large earthquakes.Predictions of this type are usually probabilistic in nature to allow for observed differences in individual repeat times and uncertainties in the parameters used in the calculations.
Abundant evidence shows that earthquakes are unstable slip repeating on existing weak planes in the earth’s topmost part, which is too cold (<300C) to deform stably. An earthquake occurs when the stress on the weak plane, which increases slowly due to plate motion, reaches the frictional strength.Two methods of earthquake forecasting are being employed - paleoseismology and seismic gaps.
Paleoseismology - the study of prehistoric earthquakes. Through study of the offsets in sedimentary layers near fault zones, it is often possible to determine recurrence intervals of major earthquakes prior to historical records.
Seismic gaps - A seismic gap is a zone along a tectonically active area where no earthquakes have occurred recently, but it is known that elastic strain is building in the rocks. If a seismic gap can be identified, then it might be an area expected to have a large earthquake in the near future.
Short-term prediction
Based on the earthquake event itself.
The public perception in many countries and, in fact, that of many earth scientists is that earthquake prediction means short-term prediction, a warning of hours to days.They typically equate a successful prediction with one that is 100% reliable. If we want to predict a plate-boundary earthquake with, say, 1-year accuracy, we need to know the strength and the current stress level with an accuracy of 0.1MPa, which way we do not know. So, we hope that Mother Nature has something more in favor of us, which we call ‘earthquake
preparation processes.Anomalous events or processes that may precede an earthquake are called precursor events and might signal a coming earthquake.Despite the array of possible precursor events that are possible to monitor, successful short-term earthquake prediction has so far been difficult to obtain.The processes that cause earthquakes occur deep beneath the surface and are difficult to monitor.Earthquakes in different regions or along different faults all behave differently, thus no consistent patterns have so far been recognized.For many large earthquakes, foreshocks are either absent or of very small size, making them unreliable for prediction purposes. Hence, the question of whether short-term prediction is possible depends on whether or not a means can be devised to detect nucleation directly, and if the form of the nucleation is predictive of the size as well as the time and the place of the subsequent event.
A prediction is a neutral statement made based on accumulated observations.A warning is a declaration that normal life routines should be altered to deal with the impending hazard.
Prediction- based on science.
Warning- Interpretations of prediction that take public policy into account.
Earthquake prediction
Ordinary people as well as seismologists have observed that, in some cases, major earthquakes occur shortly after certain anomalous events, which they then have claimed can be used for earthquake prediction.The hazards of earthquakes are avoidable if prediction can be made early, which wouldenable their mitigation, reduce damage to life and property drastically and facilitate precautionary measures.This attempt aims at establishing planetary configurations as a definitive means of earthquake prediction.
The occurrence of earthquake is a chaotic process.Scientific earthquake predictions should state where, when, how big, and how probable the predicted event is, and why the prediction is made.
Because of their devastating potential, there is great interest in predicting the location and time of large earthquakes. Although a great deal is known about where earthquakes are likely to occur, there is currently no reliable way to predict the exact time that an event will occur in any specific location.One of the earliest reported such premonitory signs is the anomalous behavior of animals.
Animals living within seismically active regions are subjected episodically to intense ground shaking that can kill individuals through burrow collapse, egg destruction, and tsunami action. Although anecdotal and retrospective reports of animal behavior suggest that although many organisms may be able to detect an impending seismic event, no plausible scenario has been presented yet through which accounts for the evolution of such behaviors.A brief review of possible seismic precursors suggests that tilt, hygroreception (humidity), electric, and magnetic sensory systems in animals could be linked into a seismic escape behavioral system. Several testable predictions of this analysis are discussed, and it is recommended that additional magnetic, electrical, tilt, and hygro-sensors be incorporated into dense monitoring networks in seismically active regions.
Probabilistic ground motion maps contour earthquake ground motions that have a common probability of being exceeded in a certain period of time. They are based on historical earthquake locations and geological information on the recurrence rate of fault ruptures, and assume that the historical trends can be projected into the future.
The occurrence of earthquake is a chaotic process.Scientific earthquake predictions should state where, when, how big, and how probable the predicted event is, and why the prediction is made.
Because of their devastating potential, there is great interest in predicting the location and time of large earthquakes. Although a great deal is known about where earthquakes are likely to occur, there is currently no reliable way to predict the exact time that an event will occur in any specific location.One of the earliest reported such premonitory signs is the anomalous behavior of animals.
Animals living within seismically active regions are subjected episodically to intense ground shaking that can kill individuals through burrow collapse, egg destruction, and tsunami action. Although anecdotal and retrospective reports of animal behavior suggest that although many organisms may be able to detect an impending seismic event, no plausible scenario has been presented yet through which accounts for the evolution of such behaviors.A brief review of possible seismic precursors suggests that tilt, hygroreception (humidity), electric, and magnetic sensory systems in animals could be linked into a seismic escape behavioral system. Several testable predictions of this analysis are discussed, and it is recommended that additional magnetic, electrical, tilt, and hygro-sensors be incorporated into dense monitoring networks in seismically active regions.
Probabilistic ground motion maps contour earthquake ground motions that have a common probability of being exceeded in a certain period of time. They are based on historical earthquake locations and geological information on the recurrence rate of fault ruptures, and assume that the historical trends can be projected into the future.
Thursday, February 17, 2011
Effects of noise pollution
Effects of noise pollution can be harmful for human.
Noise is unwanted sound.Noise from industry, traffic, homes and recreation can cause annoyance, disturb sleep and affect health.Noise is an important environmental pollutant like noxious gases that befoul our
air, water and soil.The human ear is a very sensitive instrument. If the hearing mechanisms are damaged in any way either by excessive noise levels or by diseases which affect the brain, the auditory nerve or the auditory ossicles, then hearing will be impaired.Exposure to continuous noise of 85–90 dBA, particularly over a lifetime in industrial settings, can lead to a progressive loss of hearing, with an increase in the threshold of hearing sensitivity.Noise exposure during sleep may increase blood pressure, heart rate and finger pulse amplitude as well as body movements. There may also be after-effects during the day following disturbed sleep; perceived sleep quality, mood and performance in terms of reaction time all decreased following sleep disturbed by road traffic noise.
Sources of noise pollution: traffic, concerts, airplanes, industrial machinery, construction or demolition …
Effects of noise pollution: hearing loss in humans and in animals.
Noise has become a very important “stress factor” in the environment of man. The term “noise pollution” has been recently used to signify
the hazard of sounds which are consequenceof modern day development, leading to health hazards of different type.There are many vulnerable groups of people who are most affected by noise pollution such as the young, elderly, and the hospitalized.
What can you do?
Try to use acoustical tile ceilings, wall coverings, and bookshelves to absorb sound.Close windows and doors to shut out noise from road and plane traffic.Place noisy activities next to each other, away from
areas needing quiet for concentration on quiet, learning activities.
Making a change in design and operation of machines, vibration control, sound proof cabins and sound-absorbing materials can reduce it.
Trees and shrubs may be planted in front of building to provide some absorption for the sound.
People can be educated through radio, TV, newsreels in cinema halls about noise pollution. In the family, elders can teach children to keep the radio volume low, low voice talking not to horn unnecessarily on the roads, avoid quarreling amongst each other and so on.
Noise is unwanted sound.Noise from industry, traffic, homes and recreation can cause annoyance, disturb sleep and affect health.Noise is an important environmental pollutant like noxious gases that befoul our
air, water and soil.The human ear is a very sensitive instrument. If the hearing mechanisms are damaged in any way either by excessive noise levels or by diseases which affect the brain, the auditory nerve or the auditory ossicles, then hearing will be impaired.Exposure to continuous noise of 85–90 dBA, particularly over a lifetime in industrial settings, can lead to a progressive loss of hearing, with an increase in the threshold of hearing sensitivity.Noise exposure during sleep may increase blood pressure, heart rate and finger pulse amplitude as well as body movements. There may also be after-effects during the day following disturbed sleep; perceived sleep quality, mood and performance in terms of reaction time all decreased following sleep disturbed by road traffic noise.
Sources of noise pollution: traffic, concerts, airplanes, industrial machinery, construction or demolition …
Effects of noise pollution: hearing loss in humans and in animals.
Noise has become a very important “stress factor” in the environment of man. The term “noise pollution” has been recently used to signify
the hazard of sounds which are consequenceof modern day development, leading to health hazards of different type.There are many vulnerable groups of people who are most affected by noise pollution such as the young, elderly, and the hospitalized.
What can you do?
Try to use acoustical tile ceilings, wall coverings, and bookshelves to absorb sound.Close windows and doors to shut out noise from road and plane traffic.Place noisy activities next to each other, away from
areas needing quiet for concentration on quiet, learning activities.
Making a change in design and operation of machines, vibration control, sound proof cabins and sound-absorbing materials can reduce it.
Trees and shrubs may be planted in front of building to provide some absorption for the sound.
People can be educated through radio, TV, newsreels in cinema halls about noise pollution. In the family, elders can teach children to keep the radio volume low, low voice talking not to horn unnecessarily on the roads, avoid quarreling amongst each other and so on.
Water pollution causes
Water pollution causes inadequate economic development, especially industrial development, and uncontrolled urbanisation.More recently, pollution from agriculture and aquaculture has gained prominence.
Chemical pollution of surface water can create health risks, because such waterways are often used directly as drinking water sources or connected with shallow wells used for drinking water. In addition, waterways have important roles for washing and cleaning, for fishing and fish farming, and for recreation.
Water pollution caused by various factors: heavy metals,organic pollutants,nutrients, microbial contamination, toxic organic compounds, traces of chemicals and pharmaceutical drugs, nuclear waste, salinisation, acidification...
Water, the essence of all living things, covers more than three-quarters of the Earth's surface. Water pollution has serious implications on marine life and human health.Coastal pollution of seawater may give rise to health hazards because of local contamination of fish or shellfish.
Water is a unique substance, because it can naturally renew and cleanse itself, by allowing pollutants to settle out (through the process of sedimentation) or break down, or by diluting the pollutants to a point where they are not in harmful concentrations.
Natural phenomena, such as volcanoes and algae blooms, can create
drastic changes in water quality, water is typically deemed polluted only when impaired by human contaminants.
Water pollution causes pollutants that come from a specific source such as a pipe that discharges used water or other material from a factory into a water body. Such discharges can harm the aquatic ecosystem.
They can also come from large areas such as agricultural fields that have been covered with fertilizer or pesticides.Rain water or melted snow can transfer materials such as oil, litter, fertilizers, and salt down storm sewer inlets found on the streets. In some areas, the storm sewer transports this polluted water to a water treatment facility.
Tuesday, February 15, 2011
Volcanoes erupting
Volcanoes are commonly conical hills or mountains built around a vent that connect with reservoirs of molten rock below the surface of the earth. Unlike other mountains, which are pushed up from below, volcanoes are built by surface accumulation of their eruptive products—layers of lava flows, ash flows, and ash. When pressure from gases within the molten rock becomes too great, gases drive the molten rock to the surface and an eruption occurs.
Volcanic eruptions can inject into the stratosphere tens of teragrams of chemically and microphysically active gases and solid aerosol particles that can affect the Earth’s radiative balance and climate and disturb the stratospheric chemical equilibrium.People have died from volcanic blasts. The most common cause of death from a volcano is suffocation. Volcanic eruptions can result in additional threats to health, such as floods, mudslides, power outages, drinking water contamination, and wildfires.
Volcanic eruptions can be placed into two general categories:those that are explosive, such as the 1980 eruption of Mount St. Helens, and those that are effusive, such as the gentle lava flows, fountains, and spatter cones common in Hawai'i. Many eruptions are explosive in nature.They produce fragmented rocks from erupting lava and surrounding parent rock.Non explosive eruptions are favored by low gas content and low viscosity magmas (basaltic to andesitic magmas).
Explosive eruptions are favored by high gas content and high viscosity (andesitic to rhyolitic magmas).
The major component of volcanic eruptions is magmatic material, which emerges as solid, lithic material or solidifies into large particles that are referred to as ash or tephra.Volcanic eruptions typically also emit gases, with water (H2O), nitrogen (N2) and carbon dioxide (CO2) being the most abundant.Most gases from a volcano quickly blow away. However, heavy gases such as carbon dioxide and hydrogen sulfide can collect in low-lying areas.
Volcanic eruptions can inject into the stratosphere tens of teragrams of chemically and microphysically active gases and solid aerosol particles that can affect the Earth’s radiative balance and climate and disturb the stratospheric chemical equilibrium.People have died from volcanic blasts. The most common cause of death from a volcano is suffocation. Volcanic eruptions can result in additional threats to health, such as floods, mudslides, power outages, drinking water contamination, and wildfires.
Volcanic eruptions can be placed into two general categories:those that are explosive, such as the 1980 eruption of Mount St. Helens, and those that are effusive, such as the gentle lava flows, fountains, and spatter cones common in Hawai'i. Many eruptions are explosive in nature.They produce fragmented rocks from erupting lava and surrounding parent rock.Non explosive eruptions are favored by low gas content and low viscosity magmas (basaltic to andesitic magmas).
Explosive eruptions are favored by high gas content and high viscosity (andesitic to rhyolitic magmas).
The major component of volcanic eruptions is magmatic material, which emerges as solid, lithic material or solidifies into large particles that are referred to as ash or tephra.Volcanic eruptions typically also emit gases, with water (H2O), nitrogen (N2) and carbon dioxide (CO2) being the most abundant.Most gases from a volcano quickly blow away. However, heavy gases such as carbon dioxide and hydrogen sulfide can collect in low-lying areas.
Sunday, February 13, 2011
How do earthquakes happen
How do earthquakes happen?Did you know that surface of the Earth is not one giant shell? It may look solid to us, but the Earth’s surface has cracks in it, and actually fits together like a puzzle. What happens when one of these gigantic puzzle pieces moves? An earthquake! Big earthquakes occur with movement of about a meter or two. Small earthquakes happen with movements of millimeters.Scientists cannot predict when an earthquake will take place, but they do understand why Earthquakes happen.In many ways, earthquakes are one of nature’s reminders that we are living on the thin outer crust of a planet whose interior is still cooling.The ground may feel strong and solid beneath our feet, but the tectonic plates can move without our noticing.
Most earthquakes occur at the boundaries where the plates of the Earth’s outer layer meet. In fact, the location of earthquakes and the kind of ruptures they produce help scientists define the plate boundaries. Most destructive quakes, however, are caused by dislocations of the crust. The crust may bend and then, when the stress exceeds the strength of the rocks, break and “snap” to a new position.
Earthquakes may occur in an area before,during, and after a volcanic eruption, but they are not the cause or result of volcanic activity; rather they are the result of the active forces connected with the volcanic eruption.Earthquakes are always happening somewhere.Large earthquakes occur about once a year. Smaller earthquakes, such as magnitude 2 earthquakes, occur several hundred times a day.
Measuring earthquakes
Used on the surface of the Earth, a seismograph can measure the seismic energy, or magnitude, of an earthquake. It does this by making lines on a page when the Earth vibrates. Lots of wavy lines mean the earthquake was large; fewer waves mean the quake was small.
Magnitudes are recorded on a scale called the Richter Scale.The Richter scale is the best-known scale for measuring the magnitude of earthquakes. The scale begins at 3.5, which is the magnitude assigned to earthquakes we can barely feel, to 8 or greater which are the highest magnitudes. Magnitude 8 earthquakes can destroy cities.
How can I protect myself in an earthquake?
Most earthquake-related injuries and deaths result from collapsing walls, flying glass, and falling objects caused by the ground shaking. It is extremely important for a person to move as little as possible to reach the place of safety he or she has identified, because most injuries occur when people try to move more than a few feet during the shaking.
Most earthquakes occur at the boundaries where the plates of the Earth’s outer layer meet. In fact, the location of earthquakes and the kind of ruptures they produce help scientists define the plate boundaries. Most destructive quakes, however, are caused by dislocations of the crust. The crust may bend and then, when the stress exceeds the strength of the rocks, break and “snap” to a new position.
Earthquakes may occur in an area before,during, and after a volcanic eruption, but they are not the cause or result of volcanic activity; rather they are the result of the active forces connected with the volcanic eruption.Earthquakes are always happening somewhere.Large earthquakes occur about once a year. Smaller earthquakes, such as magnitude 2 earthquakes, occur several hundred times a day.
Measuring earthquakes
Used on the surface of the Earth, a seismograph can measure the seismic energy, or magnitude, of an earthquake. It does this by making lines on a page when the Earth vibrates. Lots of wavy lines mean the earthquake was large; fewer waves mean the quake was small.
Magnitudes are recorded on a scale called the Richter Scale.The Richter scale is the best-known scale for measuring the magnitude of earthquakes. The scale begins at 3.5, which is the magnitude assigned to earthquakes we can barely feel, to 8 or greater which are the highest magnitudes. Magnitude 8 earthquakes can destroy cities.
How can I protect myself in an earthquake?
Most earthquake-related injuries and deaths result from collapsing walls, flying glass, and falling objects caused by the ground shaking. It is extremely important for a person to move as little as possible to reach the place of safety he or she has identified, because most injuries occur when people try to move more than a few feet during the shaking.
Tuesday, February 1, 2011
Facts about earthquakes
Earthquakes are short-term vibration of the Earth's crust caused by natural processes and tectonic movements in the lithosphere or artificially(caused by human activity).
Tectonic earthquakes(85%)
-resulting from tectonic movements in the lithosphere due to the sudden release of accumulated energy.Movement of molten mass in the asthenosphere causes the movement of tectonic plates where there is tension in different parts of the lithosphere.When they cross the border tension elastic substances liberated energy causes vibration of different parts of the lithosphere intensity.
Volcanic earthquakes(7%)
-Volcanic earthquakes are the result of the rapid movement of magma toward the surface, and their occurrence is mostly local and regional impacts.(often in very volcanically active areas tremors indicate the movement of magma toward the surface and points to a possible eruption)
Earthquakes collapse(3%)
-resulting from the collapse of cavities or voids in the earth's crust.
Blank spaces usually occur by dissolution of rock that are soluble in water (carbonates, evaporites). Their released energy is much smaller than the tectonic and volcanic earthquakes.Even if they have a limited impact can cause major damage.
Artificial earthquakes are caused by human activity:
-explosion,
-dive, or subsidence due to undermining and digging into the Earth's interior due to mining operations or other geotechnical engineering (mountain stroke),
-discharge of large reservoirs of water,
-pumping oil and water (shrug).
Seismograph-instrument for measuring and recording earthquake,
Seismometer-instrument to detect seismic waves,
Seismograms-records ground vibrations.
An earthquake usually starts with low blows, followed by the main shock,
followed by a weaker shock ..
Tectonic earthquakes(85%)
-resulting from tectonic movements in the lithosphere due to the sudden release of accumulated energy.Movement of molten mass in the asthenosphere causes the movement of tectonic plates where there is tension in different parts of the lithosphere.When they cross the border tension elastic substances liberated energy causes vibration of different parts of the lithosphere intensity.
Volcanic earthquakes(7%)
-Volcanic earthquakes are the result of the rapid movement of magma toward the surface, and their occurrence is mostly local and regional impacts.(often in very volcanically active areas tremors indicate the movement of magma toward the surface and points to a possible eruption)
Earthquakes collapse(3%)
-resulting from the collapse of cavities or voids in the earth's crust.
Blank spaces usually occur by dissolution of rock that are soluble in water (carbonates, evaporites). Their released energy is much smaller than the tectonic and volcanic earthquakes.Even if they have a limited impact can cause major damage.
Artificial earthquakes are caused by human activity:
-explosion,
-dive, or subsidence due to undermining and digging into the Earth's interior due to mining operations or other geotechnical engineering (mountain stroke),
-discharge of large reservoirs of water,
-pumping oil and water (shrug).
Seismograph-instrument for measuring and recording earthquake,
Seismometer-instrument to detect seismic waves,
Seismograms-records ground vibrations.
An earthquake usually starts with low blows, followed by the main shock,
followed by a weaker shock ..
Monday, January 31, 2011
Natural resources on Earth
Natural resource or natural capital is the planet’s air, water, soil,wildlife, mineral and natural purification , recycling, and pest controlprocesses. Solar capital is the energy from the sun.
Natural resources are:
* Air, water and soil
* Biological resources - plants and animals
* Raw materials (like minerals)
* Space and land
* Wind, geothermal, tidal and solar energy
Natural resources are often classified into renewable, flow, and non-renewable resources.
Ecological resource- is anything required by organisms like you for normal maintenance,growth and reproduction.Examples are water,shelter, food, and habitat.Ecological resources include fish and wildlife populations, habitats, and their relationships to each other and the environment/ecosystem.
Economic resource- is anything obtained fromthe environment to meet your needs and wants. Examplesare food, water, shelter,manufactured goods,transportation,communication and recreation.
We have a lot of resources to meet our needs. Some of these resources are finite.Other resources are renewable but it takes time to replace or replenish them. Unfortunately,the rapid consumption of these raw materials by our expanding population has led to the exploitation of the natural resources. Exploitative attitudes of humans rapidly reduce theavailability of natural resources.
Natural resources are:
* Air, water and soil
* Biological resources - plants and animals
* Raw materials (like minerals)
* Space and land
* Wind, geothermal, tidal and solar energy
Natural resources are often classified into renewable, flow, and non-renewable resources.
Ecological resource- is anything required by organisms like you for normal maintenance,growth and reproduction.Examples are water,shelter, food, and habitat.Ecological resources include fish and wildlife populations, habitats, and their relationships to each other and the environment/ecosystem.
Economic resource- is anything obtained fromthe environment to meet your needs and wants. Examplesare food, water, shelter,manufactured goods,transportation,communication and recreation.
We have a lot of resources to meet our needs. Some of these resources are finite.Other resources are renewable but it takes time to replace or replenish them. Unfortunately,the rapid consumption of these raw materials by our expanding population has led to the exploitation of the natural resources. Exploitative attitudes of humans rapidly reduce theavailability of natural resources.
Sunday, January 30, 2011
How do tectonic plates move
Plate tectonic theory has developed slowly and progressively since it was developed in the 1960s. It is a theory that truly has the entire world as its experiment.According to the theory of plate tectonics, the Earth's crust and upper mantle are broken into moving plates of "lithosphere." The lithospheric plates are solid rock. There are several very large plates, each consisting of both oceanic and continental portions.There are a dozen or more smaller plates. The plates average about 80 kilometers (50 miles) in thickness.All of the plates are moving. They are slow, moving at speeds of centimeters to tens of centimeters per year. They slide along on top of an underlying mantle layer called the asthenosphere, which contains a little magma (molten rock). Many types of evidence indicate that the plates move.All objects on and in the Earth are pulled towards its center by the force of gravity. This may affect the plates at converging plate boundaries in areas called subduction zones, where one plate sinks into the mantle.At the midocean ridges, the plates are separating, pulled apart by the motion of convections cells beneath the plates. Lava then comes up to fill in the resulting gap and cools into solid rock when it comes into contact with cold ocean water,becoming new, young ocean floor. The ocean floor cools more as it ages (making it contract) and more and more sediments pile on top of it, so it becomes more and more dense with time. As the ocean floor moves away from the mid-ocean ridge (“sea-floor spreading”), it either pushes a continent (“continental drift”) or runs intoanother plate, leading to earthquakes.The movements of plates over millions of years resulted in the opening and closure of oceans and the formation and disassembly of continents.There are three principal types of plate boundary (divergent, convergent, and transform).
Plates move apart at divergent plate boundaries such as the oceanic ridge system that separates the North American and Eurasian plates in the north Atlantic Ocean. Plates crash into each other along convergent plate boundaries marked by volcanoes and mountain belts. Finally, plates slide past each other along a transform plate boundary such as the San
Andreas Fault, California, that separates the North American and Pacific plates.
Plates move apart at divergent plate boundaries such as the oceanic ridge system that separates the North American and Eurasian plates in the north Atlantic Ocean. Plates crash into each other along convergent plate boundaries marked by volcanoes and mountain belts. Finally, plates slide past each other along a transform plate boundary such as the San
Andreas Fault, California, that separates the North American and Pacific plates.
Saturday, January 29, 2011
Magnetic field of the Earth
Earth's magnetic field is slightly tilted with respect to the planet's spin axis; there is currently a difference of about 11° between the two. Earth's magnetic field extends thousands of kilometers (miles) outward into space. The field forms a gigantic magnetic "bubble" in space around Earth. This magnetic bubble is called the magnetosphere.In addition to sources in Earth’s core, the magnetic field observable at the planet’s surface has sources in the crust and in the ionosphere and magnetosphere.Today the north magnetic pole is located about 700 miles(1,200 km) south-southeast of the north (spin) pole of the Earth (see red star on globe to left). Many times in the history of the Earth the core’s electrical currents have reversed direction, causing the north and south magnetic poles to switch positions!
The strength of the field at the Earth's surface ranges from less than 30 microteslas (0.3 gauss) in an area including most of South America and South Africa to over 60 microteslas (0.6 gauss) around the magnetic poles in northern Canada and south of Australia, and in part of Siberia.The field is similar to that of a bar magnet, but this similarity is superficial. The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated spins of electrons and nuclei within iron atoms. The Earth's core, however, is hotter than 1043 K, the Curie point temperature at which the orientations of spins within iron become randomized. Such randomization causes the substance to lose its magnetic field. Therefore the Earth's magnetic field is caused not by magnetized iron deposits, but mostly by electric currents in the liquid outer core.
The strength of the field at the Earth's surface ranges from less than 30 microteslas (0.3 gauss) in an area including most of South America and South Africa to over 60 microteslas (0.6 gauss) around the magnetic poles in northern Canada and south of Australia, and in part of Siberia.The field is similar to that of a bar magnet, but this similarity is superficial. The magnetic field of a bar magnet, or any other type of permanent magnet, is created by the coordinated spins of electrons and nuclei within iron atoms. The Earth's core, however, is hotter than 1043 K, the Curie point temperature at which the orientations of spins within iron become randomized. Such randomization causes the substance to lose its magnetic field. Therefore the Earth's magnetic field is caused not by magnetized iron deposits, but mostly by electric currents in the liquid outer core.
The ozone layer
Ozone is a triatomic molecule, consisting of three oxygen atoms.Ozone in the lower atmosphere is an air pollutant with harmful effects on the respiratory systems of animals and will burn sensitive plants; however, the ozone layer in the upper atmosphere is beneficial, preventing potentially damaging ultraviolet light from reaching the Earth's surface.Ozone is a pale blue gas, slightly soluble in water and much more soluble in inert non-polar solvents such as carbon tetrachloride or fluorocarbons, where it forms a blue solution. At –112 °C, it condenses to form a dark blue liquid. It is dangerous to allow this liquid to warm to its boiling point, because both concentrated gaseous ozone and liquid ozone can detonate. At temperatures below –193 °C, it forms a violet-black solid.
Ozone layer
The highest levels of ozone in the atmosphere are in the stratosphere, in a region also known as the ozone layer. Ozone used in industry is measured in ppm(OSHAexposure limits for example), and percent by mass or weight.This layer absorbs 97–99% of the Sun's high frequency ultraviolet light, which is damaging to life on Earth.[1] It is mainly located in the lower portion of the stratosphere from approximately 13 to 40 kilometres (8.1 to 25 mi) above Earth, though the thickness varies seasonally and geographically
Ozone was discovered by Christian Friedrich Schönbeinin 1840, who named it after the Greekword for smell (ozein), from the peculiar odor in lightning storms.The odor from a lightning strike is from electrons freed during the rapid chemical changes, not the ozone itself.
Ozone layer
The highest levels of ozone in the atmosphere are in the stratosphere, in a region also known as the ozone layer. Ozone used in industry is measured in ppm(OSHAexposure limits for example), and percent by mass or weight.This layer absorbs 97–99% of the Sun's high frequency ultraviolet light, which is damaging to life on Earth.[1] It is mainly located in the lower portion of the stratosphere from approximately 13 to 40 kilometres (8.1 to 25 mi) above Earth, though the thickness varies seasonally and geographically
Ozone was discovered by Christian Friedrich Schönbeinin 1840, who named it after the Greekword for smell (ozein), from the peculiar odor in lightning storms.The odor from a lightning strike is from electrons freed during the rapid chemical changes, not the ozone itself.
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