One hazard can often trigger others (e.g. Earthquakes can cause landslides and tsunamis). The San Andreas Fault is a conservative plate boundary that runs 1300km along the Californian coastline. The fracture within the crust, causes crustal instability, between the North American and the Pacific plate. As it traverses, due to convection currents, the tectonic plates are dragged along the entire length of the Californian coast.
For constructive plate margins, the magma rises up into the gap that created by the plate move apart to form a volcano. After that for earthquakes, after that for the earthquakes, it occur at all three types of plate margins. They are caused by tension that build up at the plate margins, for destructive plate margins, the tension build up when one plate get stuck as it’s moving down past the other into the mantle. Then for constructive margins, the tension builds along cracks within the plates as they move away from each other. At last for conservations margins, the tension build up when plate are grinding past each other get stuck.
2. Lava Flows is the lava that slide down the side of the volcano. The dangers of hot lava meeting the surface are streams that resulted from the boiling of the salt water and the instantaneously change to a crystal. The water temperature where lava meets water is 30 -69. Volcanic Gases 1.
However despite this, as 95% of earthquakes occur on plate boundaries there must be some kind of link between the two and plate tectonic theory can explain this. The theory suggests that the earth’s crust is split into plates which are huge slabs of rock that move due to the convection currents in the mantle. Where two plates meet it causes friction along the plate margin and this creates stresses in the lithosphere and tension in the rock builds overtime. When the strength of the rocks under stress suddenly breaks, they fracture along cracks called faults, sending a series of seismic
A hazard is a situation that poses a level of threat to life, health, property or environment. The level of hazard posed by different volcanoes can very greatly, from a weak eruption with minimal impact that causes little damage, to a violent and life threatening explosion. Most of the sixty-plus volcanoes that erupt each year are low risk, however a combination of factors can cause a volcano to be a serious hazard. The factors causing these variations will be explained in this essay. The first factor that must be considered is the viscosity of the magma.
This type of magma is dangerous because it has a tendency to plug the volcano, trapping gasses which build pressure and eventually erupting violently! This is evidenced in subduction volcano's like Mt. St. Helens and Krakatoa are common types of these volcano's. The magma plugs the volcano which creates and increase in pressure and latent heat which eventually creates a huge explosion. They release enormous amounts of energy and create eruption columns of gas and ash that can rise up to 50 km (35 miles) high at speeds of hundreds of meters per second.
In this convergent boundary, the denser Nazca Plate is being subducted beneath the less dense continental lithosphere of the South American tectonic plate. As the plate descends it causes earthquakes in the Benioff zone, and volcanoes occur here because of melting of the plate in the asthenosphere. The southern end of the plate dips at a steep angle, while the northern end may be experiencing flat-slab subduction (in which the oceanic plate slides below the continental plate at a very low angle). A low angle of subduction may explain the relative lack of volcanic activity in the Northern part of Chile, compared to the extremely active southern volcanic mountains. Whereas Eyjafjallajokull is in Iceland, an MEDC.
Volcanoes are found mainly in three locations, at constructive and destructive plate margins and at hotspots. The most dangerous volcanoes occur at destructive, convergent plate margins. Here one plate subducts beneath the other, and as it descends, friction, increasing pressure, and heat from the asthenosphere and mantle melt the plate to form an acidic magma chamber. The magma at these boundaries is andesitic and rhyolitic, meaning that they have a high viscosity. Because of this the lava is resistant to flow and often forms blockages in vents.
Discuss the view that the impact of earthquake hazards depends primarily on human factors  An earthquake is a tremor or shockwave in the earth’s crust that is caused by the sudden movement of the crust, resulting in the earth shaking. Most earthquakes are a consequence of tectonic plate movement by tension causing a sudden release of energy or rubbing. These normally occur at plate margins or along fault lines and can cause hazards which need to be prevented where possible. Earthquakes can therefore occur at all plate boundaries, destructive, constructive and conservative but the most damaging tend to happen at destructive margins where the earthquakes have a high magnitude due to the rubbing of the oceanic and continental crusts. A hazard is a natural event that has the potential to effect both life and property.
Case Study- Geomorphologic Hazards Dorset landslide By Carra Wilson A geomorphological hazard is a hazard that occurs due the land moving above the surface. They believe that the land slide occur in this area due to heavy rain over the period before the event combined with a recent heat wave in the area cause the land to become unstable resulting in the land slide as the limestone was just crumbling away from the rest of the cliff. The process in which caused the land to move is commonly known as slumping. Slumping is caused when rain water sinks through the porous rocks but once it reaches the underlying clays it can sink no further. The water builds up along the junction between the rock layers and seeps out of the cliffs as a series of springs.