Secondary Vents are extra vents that the lava seeped through Secondary Cones are built by lava and are on the volcano. The risks to people and property from volcanic eruptions are being destroyed by lava. Some risks to people are suffocation to the gas cloud. You can predict volcanic ruptures because there will be ground shaking, increase in temperature and the Earth’s surface will began to bulge. What role have volcanoes played in the evolution of life on the planet?
At last for conservations margins, the tension build up when plate are grinding past each other get stuck. Afterwards the plate will finally jerk past each other and sending out shock waves which is vibrations which is earthquakes. They both create lots of impact. For examples for the volcano eruption in Montserrat which is a LEDC, it cause 19
This transfer allows quantifying the influence of blasting waves on the rock mass of the slope and on soil slopes. In this paper, the effects of waves’ frequency and Rayleigh’s surface waves are discussed as well as the slope characteristics such as its rock mass. Transfer of Analytical Techniques from Earthquake Engineering The similarity between blasting vibrations and earthquake motions is known. A simple example is the use of blasting-induced vibrations in experiments built to predict earthquake response of a building structure. According to Dowding (1988) two levels of analysis can be considered.
Wegener's theory also provided an alternate explanation for the formation of mountains (orogenesis). The theory being discussed during his time was the "Contraction theory" which suggested that the planet was once a molten ball and in the process of cooling the surface cracked and folded up on itself. The big problem with this idea was that all mountain ranges should be approximately the same age, and this was known not to be true. Wegener's explanation was that as the continents moved, the leading edge of the continent would encounter resistance and thus compress and fold upwards forming mountains near the leading edges of the drifting continents. The Sierra Nevada Mountains on the Pacific coast of North America and the Andes on the coast of South America were cited.
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.
The evidence of sea floor spreading was further supported by Vine and Drummond, who studied the magnetic pattern of the sea floor. They found that the Earth’s magnetic field changes over time, because as magma from the mantle rises to the crust it cools but the basalt will align to the field it cools to. It is also found that on either side of mid oceanic ridges there were symmetrical magnetic patterns, so suggesting that the ocean was created at the mid oceanic ridges and as new ocean floor cooled, it pushed the crust away. Both Hess and Vine and Drummond found evidence that is crucial to the explanation of how continental drift happened, and it is very important in the development of geologists understanding, however other people found evidence to support continental drift also. Dan McKenzie went on to further explain sea floor spreading, being able to explain why new crust was made at mid oceanic ridges.
This knowledge of plate margins and their movement against one another can help us to understand the distribution of seismic and volcanic events and this is because the majority of events are associated at these plate margins. Wegener’s theory of plate tectonics suggests that all the continents were once joined together in a super continent called Pangea and have since drifted apart due to plate tectonics. To add to this, Sea floor spreading was discovered showing that rock is being created and destroyed, leading us to believe in the existence of plates and plate boundaries. Wegener gained evidence from paleo magnetism and suggested that there were numerous reasons and pieces of evidence for the continents drifting apart. Biologically, there was evidence that proved his theory for example, the Mesosaurus reptile fossils were only found in Africa and South America, proving his ‘jig-saw’ fit idea.
The causes of earthquakes are tectonic plates moving suddenly, for example when the plates get snagged and caught on one another. There are two types of plate boundaries which cause earthquakes, convergent and transform. Convergent boundaries which is the pushing together of two plate boundaries and one plate slips under the other, as this happens the plate gets stuck and a sudden jolt of the plate happens when it becomes unstuck, this creates a earthquake. transform plates, which is two plates rubbing against each other, as they are moving across each other they get stuck on protruding rock, as this is broken down, the plate suddenly moves creating a quick and sudden earthquake. An example of a transform plate is the San Andreas Fault; this fault is caused when the Pacific plate and North
What did Harry Hess propose in 1963? He proposed that molten rock erupts from the Earth's interior along mid-oceanic ridges, creating new seafloor. What magnetic field, polarity evidence supports the theory of plate tectonics? -the earth's magnetic field was especially strong over the oceanic ridges that were made up of iron rich materials -the magnetic field formed a zebra-striped
'Volcanoes and seismic events are major pieces of evidence towards proving that plate tectonics theory is valid.' Discuss the extent to which you agree with this view (40 marks) The modern theory of plate tecctonics is a fairly new idea, developed in the last 100 years. It is now generally accepted as the explanation for seismic and volcanic activity. The theory, developed by Alfred Wegenger in 1912, states that the lithosphere is made up of seven large and several other smaller plates. He believed that all of the continents were once joined together, forming a super-continent called Pangaea.