Volcanoes Distribution Volcanoes can be described as being tectonic hazards that occur in many parts of the world. The distribution of volcanoes is closely linked with the positioning of the tectonic plate boundaries across the globe. Today there are about 500 active volcanoes in the world. The world map of volcanoes in your atlas shows that the most volcanic activity occurs along the West coasts of North and South America, (along the Rockies and Andes) and the coasts of many Far East countries (in areas like Japan, China etc). The positioning of these volcanoes coincide with major plate boundaries. E.g. the volcanoes along the West coast of North America are the result of the Juan de Fuca plate converging with the North American plate. Another example is the volcanoes formed in the Andes Mountains are a result of the convergence of the Nazca and South American plates. Other areas that have high volcanic activity are along the plate boundaries of the Eurasian and African plates. Most of the volcanic activity on Earth occurs on the island of Iceland. Which is due to the formation of the Mid-Atlantic ridge, which is where two tectonic plates are diverging away from each other. Features Volcanoes release large amounts of energy from beneath the lithosphere, (Earth's crust and upper part of the mantle) and asthenosphere, (semi-molten mantle). During volcanic eruptions molten rock or magma rises up from the asthenosphere towards the surface as it's propelled by gases surrounding it. Some eruptions can occur through cracks in the Earth's surface called fissures. As magma reaches the surface, it's called lava. Common features o... ... middle of paper ... ...e media respond much faster. · This is due to the bureaucratic nature of multi level government, which requires numerous studies before anythin effective is accomplished. KT 38; Local, national and supranational responses. Local responses, cycled through shock, mourning and then anger for those who had 'allowed this to happen'. KT 39; Costs; economic and human. · Total economic damage of around $10 billion. · 42 died in Oakland, 60 miles from the epicentre. 400 injuries from the Cypress structure. · 59 water mains burst, but 100+ gas mains were ruptured. · 10 000 were left homeless, 62 died.· The Nimitz highway, and Cypress structure, and sections of the Bay Bridge collapsed, due to structural failure. They were subject to ten times the amount of force for which they were designed.
The physical damage done to San Francisco due to the earthquake was extensive. The earthquake caused gas lines to rupture and chimneys to collapse which resulted in perhaps the greatest devastation from the earthquake, the fires. About fifty fires broke out around the city that in combination with the earthquake caused the destruction of about 28,000 buildings (The Great San Francisco Earthquake: One of America's Worst Urban Disasters. 2005). The fires continued to burn for four days because the water mains had burst; therefore, the hydrants had no water. Desperation sunk in and the fire department and military, having no water to stop the fires, used dynamite to create firebreaks. This ultimately backfired and led to the fires expanding. When the fires stopped, the city was left in ruins with 80% of it being destroyed (Dean. Pg 506).
Ten million California residents who lived closely from the major fault lines could have been endangered in many extreme ways. (House, 56). A tragic thing was that after the earthquake a multitudes of fire followed right after. The situation led to the water mains being destroyed and the firefighter being left with no water to settle the growing fire which continued blazing. The bay water was planned on putting all of the dure out but it was to far in distance to be able to transport it (Earthquake of 1906, 2). The firefighters who were putting out the fire were either surrounded or being burned by the fire that was blazing in all directions (San Francisco Earthquake, 2). A resident who was present during the event mention that he/she saw men and women standing in a corner of a building praying, one person who became delirious by the horrific ways that were surrounding him while crying and screaming at the top of his lungs “the Lord sent it, the Lord”. Someone also mentioned that they experience themselves seeing Stones fall from the sky and crushing people to death. Reporters say there were 100 cannons going off (San Francisco Earthquake, 3). People who lived fifty miles away from the fire was able to “read the newspaper at
The 1930-50’s golden era of organized labor is over and has lost the energy it had once had as a unifying factor in the lives of workers in the U.S. There are many factors to this decline, but image is very influential in the creation and influence of unions in two ways: externally and internally. Externally, the union’s ideology and actions attract workers into becoming members of a union and how government responds to a union’s beliefs and actions. Internally, union’s are run democratically, where workers choose who will represent them in negotiations with employers, which should give some benefits to the majority of the workers in the union. Organized crime's infiltration into labor unions has rotted the image of unions who represent workers looking to defend themselves against employers and achieve a stable livelihood. The history of labor and organized crime are undoubtedly linked because at times they would use each other to further their own means: the most famous of these links would have to be on James Hoffa. Organized crime and corrupt union officials influence on unions will still exists and although crackdowns throughout the decades have made some progress I doubt that they will be removed entirely from labor.
Volcanism is a major part of the Galapagos and their formation. The island chain is positioned on the Nazca Plate, which is subducting beneath the South American Plate at a geologically rapid pace of 2.5 inches per year. In addition, this Nazca Plate is located directly on top of the Galapagos Hotspot. It is here that mantle plumes melt Earth’s crust, creating volcanoes as a product. The oldest island was first shaped by this ...
Basalt forms due to the partial melting of the layer of the mantle called the asthenosphere. The asthenosphere is the plastic zone of the mantle beneath the rigid lithosphere. Mantle plumes coming from the mesosphere can cause the asthenosphere to melt with heat or even if pressure decreases, which is called decompression melting (Richard 2011). The magma that forms from this melting is mafic magma that solidifies once it reaches the earth’s surface and cools quickly. The above process mainly occurs mainly during intraplate igneous activity which is the main explanation for volcanic activity that occurs a long distance away from a plate boundary. If the tectonic plate above the mantle plume is moving it can create a string of volcanic activity such as in Hawaii. See Fig 2.
First you might need to know definition of tectonics. It is a theory in geology. The lithosphere of the Earth is divided into a small number of plates which float on and travel independently over the mantle and much of the Earth’s seismic activity occurs at the boundaries of these plates. That is the official definition of Plate tectonics. secondly, this plate covers many parts of continents. plate boundaries don’t go according to Continents boundaries, they make their own boundaries. The North American plat...
Volcanoes. The naturally forming landforms that can look remarkably beautiful. Gentle slopes, or high rising heights with snow caps and greenery that seems to attract many tourists and sightseers around the world. These magnificent landforms can also cause major destruction and can produce forces that can explode, burn, and create a great deal of damage. Two of these extravagant wonders of the world is the Mount Saint Helens composite volcano in Washington, US, and the Mauna Loa shield volcano in Hawaii, US. These landforms have a eruption history of many colors. One has a great power in eruption, but another has a eruption that is quiet and gentle. In comparing these two volcanoes there are many likes, and dislikes, to consider. So the following
Stories about volcanoes are captivating. Myths come in different versions, but all of them are capable of capturing yours, and everybody’s imagination.
Super volcanoes are formed when magma rises from the mantle to create a scorching reservoir in the Earth's
Volcanoes are one of natures most interesting and dangerous phenomenons. The way volcanoes operate can be understood, on a basic level, by just some simple physics and chemistry, this paper will investigate and explain some of the basic physics that govern the behavior of volcanoes.
Volcanoes can be one of the most destructive forces on Earth. It is estimated that some
While the early warning saved thousands of people, the Japan’s Meteorological Agency underestimated this earthquake as the subduction zone of Japan should not produce the magnitude 9.0 quake (Oskin, 2013a). The Tohoku Earthquake and its tsunami approximately killed 16 thousand people, injured 6 thousand people and around 3 thousand people were missing. Most people died from drowning. Around 300 thousand buildings, 4000 roads, 78 bridges, and many more were affected by the earthquake, tsunami, and fires from leaking oils and gas. Electricity, telecommunication, and railways were severely damaged. The debris of 25 million tons was generated and carried out to the sea by water (BBC News, 2012). The country’s authorities estimated more than 309 billion US dollars of damages. Landslides occurred in Miyagi and liquefaction in Chiba, Tokyo, Odaiba, and Urayasu (USGS, 2013). Furthermore, the tsunami destroyed protective tsunami seawalls. Approximately 217 square miles of Japan covered in water (Oskin,
Mount Vesuvius is a volcano located in southern Italy, near the bay of Naples and the city of Naples. It is the only active volcano on the European mainland. Vesuvius rises to a height of 1277 m (4190 ft). Vesuvio (Vesuvius) is probably the most famous volcano on earth, and is one of the most dangerous.
The interior structure of the earth is made up of crust, the mantle and core (inner core and outer core). Earthquakes occur on the crust. Crust forms the external layer of the earth surface. On the crust, the plate tectonics forces are in charge of causing the abrupt earth movements. Due to the existence of an immense temperature and concurrent pressure difference in the outer layer and inner layer of the earth, convection currents occur at the mantle. This energy results from overwhelming decomposition of radioactive substances contained by the rocks found at the interior of the earth. The developed convection currents lead to movement of lava; cold lava finds its way to the interior of the earth crust, while the molten lava which is generally hot, leaves the interior of the earth to the outside of the earth crust. These kinds of circulations occur at different locations of the earth surface and consequently results in segmentation of the earth due to movement in different directions.