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
Each year, around 60 major volcanoes erupt globally. How hazardous each eruption is depends on a variety of physical and human factors. This essay will analyse how physical volcanic properties interact with human variables to make certain volcanoes more hazardous than others. This will be identified through the numerous recorded eruptions from different countries at different stages of development. Since the degree of impact an earthquake has is measure on both the Richter and the Mercalli scale, it must be reasonable to assume that the power of an eruption is representative to the degree of how potentially hazardous the event may be.
The difference in pace and movement of plates, triggers the up build friction. When this friction is released- Earthquakes are generated. An example of an event is the San Francisco earthquake in 1989 on October 17 measuring 6.9 on the Richter scale. Tsunamis are one result of earthquakes. A sudden shift in
Over time weathering takes over the igneous rocks. Sediments from the weathered rocks moves downward by running water, wind, waves, and many other erosional agents. The next step is lithification. The sediments become tightly packed down in the depths of earth and encounters massive amounts of pressure and heat. A metamorphic rock is now formed.
This earthquake occurred on the Denali-Totschunda fault system – one of the longest strike-slip faults in the world. The tectonic setting of this area results from the interaction of the Pacific plate (oceanic) and the North American plate (Continental). This results in the subduction of the Pacific plate beneath the N.American plate because the continental plate is thicker and less dense and sudden movements in this subduction results in an earthquake such as the one experienced in Denali in 2002. This earthquake measured 7.9 on the Richter scale and violent shaking of the ground triggered many landslides which buried valleys and glaciers. The one service that was damaged the most was the Northway airport – this was the effect of ‘liquefaction’ caused by the rupture transforming water saturated sediments into a liquid slurry.
Just like the characteristic of a rock, climate also plays a role in the rate in which a rock will break down. With that being said, rocks that are exposed to a wet/ moist climate are more susceptible to chemical weathering. Thus, the rocks in this type of climate will decompose at an accelerated rate. On the other hand, dry climates are more vulnerable to mechanical weathering, which has a slower weathering rate. All in all, areas with warm temperatures will have faster chemical reactions, so, weathering in the tropics is rapid.
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.
The break in tension causes a jerk and the sea floor to spring upwards. This causes the continental plate to spring upwards creating an earthquake. When the sea floor springs upwards the displaced water travels in opposite directions away from the earthquakes epicenter across the ocean. In deep water the waves travel fast and are
Explain why the Philippines and California multiple hazards hotspots are affected by disasters in different ways?? Disaster hotspots are multiple hazard zones such as the Californian Coast and the Philippines. They are places which experience more than one hazard. California is on a conservative plate boundary where two plates (The North American and Pacific) are sliding past each other at different speeds and pressure hence generating frequent shallow focus earthquakes. This includes San Andreas Fault where a network of active faults underlies the LA region and San Francisco Bay Area.
Provides insightful explanation of connections between reasons, facts, details and controlling ideas. | 10 | | Content is comprehensive, accurate, and/or persuasive. | 10 | | * Major points are supported by specific details, examples, and/or analysis. Provides specific, relevant, extensive and compelling reasons, facts, and details | 10 | | There is integration of theory and practice whereby the writer is able to link theories to practical experience. | 10 | | Where appropriate, the paper supports major points with theory relevant to development of the ideas, and uses the vocabulary of the theory correctly.