Most volcanoes occur at a plate margin because this is the area where the magma is produced. At constructive (divergent) plate margins the magma is produced by the melting of the mantle below the surface and so this produces a basic lava which allows it to flow easily. These types of volcanoes eg, Mid-Atlantic Ridge erupt frequently but do not produce devastating results, they are associated with lava flows and ash. On the other hand volcanoes on destructive (convergent) margins (plates moving towards each other) are much more violent and hazardous. The formation of an ‘acid magma chamber’ is caused by one plate subducting below the other which causes intense pressure and heat causing the melting of rocks and sediment. Because the lava is very viscous and doesn’t flow very easily it allows huge amounts of pressure to build up which can lead to a catastrophic eruption involving pyroclastics.…
While in class, we have learned many things about the earth and its elements that are within it. One thing about the earth that we have learned about is volcanoes. The text describes a volcano as a hill or a mountain that is constructed by the extrusion of lava or rock fragments from a vent (Plummer, 2007).…
A volcano is an earth hazard that occurs on faults between tectonic plates on a destructive boundary and an eruption is a natural disaster. A primary impact happens immediately after the disaster and before any response like death or collapsing or destruction of buildings. A secondary impact occurs later after the disaster, such less farm produce or a reduction in tourism. The severity of these impacts will differ considerably in a MEDC and LEDC where volcanic eruptions have taken place. These may be seen in the Mount St. Helen volcano eruption as well as in the Iceland volcanic eruption. They may also show that the impacts vary from volcano to volcano, place to place.…
Volcanic eruptions happen all across the surface of the globe, many argue that if controlled and monitored they would have little effect on the population. However others argue that some volcanic events are too powerful or unpredictable to control.…
Events that cause death, injury and damage to property and infrastructure are known as natural hazards. Volcanic eruptions can swiftly become natural hazards which can quickly lead to major loss of life and widespread damage.…
There are several causes of volcanic eruptions. When magma forces its way up to the crust of the earth, this causes an eruption (Langley,2006). Therefore, the more scientists learn about magma, the more they learn about eruptions. During certain eruptions, up to 1.5 million tons of lava can be spewed per second(Heenan,2014). This shows scientists how dangerous volcanoes can be. Debris and smoke shoot out of the volcano right before it erupts (A+E network,2010). It would seem that this is enough warning that the volcano is going to erupt.…
One factor that heavily influences how hazardous a volcano is, is the plate boundary that it lies on. Subductive plate boundaries tend to produce much more violent eruptions than conservative or constructive margins. Subductive boundaries occur where two plates (one continental and one oceanic) are moving toward each other. The denser plate, the oceanic, is forced underneath the continental. As it subducts into the asthenosphere, it begins to turn back into magma. This magma is light and less dense than the asthenosphere, so it rises and forces its way through weaknesses in the crust. This is how volcanoes are formed on subductive margins. An example, is the Aleutian Islands which are a chain of volcanoes formed by the subduction of the pacific oceanic plate underneath the Eurasian/north American (?) plate.…
A hazard can be defined as a situation that poses a threat to life, health, property or the environment. The severity and type of volcanic hazards that occur are mainly dependent on the type of magma. Volcanic processes can be split into two categories – primary hazards and secondary hazards. The primary hazards that can occur are pyroclastic flows, lava flows, tephra and poisonous gases. The secondary hazards include Lahars, volcanic landslides, tsunamis flooding and volcanic storms. The overall impact of volcanoes as a natural hazard varies greatly from one time and place to another. This is because it depends on the volcanic event, the population density of the surrounding area, the wealth of the area, the weather at the time and sometimes the culture of the inhabitants of the area. Vulcanicity is normally associated with plate tectonic processes and occurs along constructive plate margins, destructive plate margins or above hotspots.…
Volcanoes are magnificent formations from an opening in a planet’s crust. They form when magma, volcanic ash, and gases escape from a magma chamber below the surface of the planet. Tectonic plates cover the surface of the planet and are constantly moving. Volcanoes are generally found where these plates converge or diverge. Not only are volcanoes found in these areas but also where the Earth’s crust is stretching or thinning. There are volcanoes that form away from plate boundaries in areas that are called “hot-spots”. An example of “hot-spot” volcano formation is the Hawaiian Islands.…
The eruptions, while sometimes are relatively quiet they produce lava flows that creep across the land moving between 2 and 10 miles per hour. These resulting lava flows stream molten rock which destroys everything in its path. It usually moves slowly enough the people can move out of its way. These eruptions can trigger other natural hazards such as earthquakes, mudflows and flash floods, rock falls and landslides. Wild fires and tsunamis are additional hazards that might be triggered by a volcanic eruption.…
Volcanoes may be both harmful and helpful to the earth. They are helpful because, they deposit minerals into the ground to make the soil richer and better for plants. They are also helpful because they can provide as a safe oasis once they have erupted for rare and not rare plants and animals. Although they may be very helpful they may also be very harmful. This is because, of how many could be going off at once. These are just some of the many ways volcanoes help to shape and affect our earth, people, and…
They are formed near destructive plate boundaries where material from a plate that is descending rises back to the surface, this magma then rises up creating the large bubble of magma below the overlaying rock. They are also formed at continental hotspots, in either situation; the continental crust is being extended locally. This then makes weaknesses that allow the magma plumes to rise over very long periods of time and this process occurring over so much time (in some cases hundreds of thousands of years) is why the magma lakes have such an colossal mass.…
A volcano is actually an opening or a fissure, in the Earth's crust, through which lava or molten rocks, ash and toxic gases present below the surface of Earth are discharged by a sudden, violent eruption. Sometimes, it can be a mountain-like structure with a bowl-shaped depression at the top, through which these substances are expelled. The term 'volcano' is derived from the name of the Roman God of fire, Vulcan.…
Volcanoes are formed when plates collide or move away from one another thus they are usually found at the edge of tectonic plates .Volcanoes can also occur in the interior of plates, these volcanoes are commonly known hotspots.…
Volcanic activity mainly tends to occurs on the edge of plate margins, but could potentially occur at any location, such as Hawaii where the plate boundary is underneath a hot spot, which causes the Hawaiian chain islands. It is where the magma in the mantle breaks through the lithosphere to form extrusive landforms.…