Tsunami waves travel at velocities of several hundred kilometres per hour and easily make it to the far side of an ocean in about the same time as a passenger jet. In 1883 the volcanic eruption of Krakatoa resulted in the collapse of a caldera that initiated a tsunami which killed 36,000 people on nearby islands. These movements create waves which propagate through the earth. Shaking and Ground Rupture This is a primary effect of an earthquake. High rates of appreciation occur in high-risk areas, but the only question is the partial impact of unanticipated-hazard events on these property values. In geological terminology, this meeting point is known as fault line. When a tsunami approaches the shore, the water depth decreases, the front of the wave slows down, the wave grows dramatically, and surges on land.
Do you find they behave more rationally when it comes to material things—such as a house, a car, physical damage—and less rationally when it becomes their perception of personal risk? It may be difficult to account for the true social impacts that a major earthquake might have on staff and their ability to attend and focus at work in the days and weeks following the disaster. Such results suggest that there is a market response to disasters. What is the nature of disaster relief, if one is not protected if these mitigation measures are not taken? But we can be better prepared to meet earthquakes by: i. More recently it has been learned that the same forces can also cause tremors. I think of this in relation to the nuclear power debate, where the material risks are relatively negligible but the personal, perceived risks are enormous. There is a tendency to think about these events by saying that the probability is very low or I am not going to worry about the consequences. As shown in Figure 11.
Expectations and Economic Effects of Disasters The primary factor generating long-run effects of a serious earthquake is the change in expectations of future returns to capital investment and real wages of labor in the region. This book presents the proceedings of an August 1990 forum held at the National Academy of Sciences in Washington, D. A landslide buried the village of Sujiahe in Xiji County. When an earthquake happens Figure 11. Third, evidence on how uncertain natural-hazard events enter an economic model of development of a regional economy is considered.
If the future is discounted by a very large interest rate, a relatively small benefit results from the mitigation measure if an earthquake occurs. The second presentation will be made by Professor Howard Kunreuther and is a joint effort with his coauthor, Professor Neil Doherty. Preparing Structures for Shaking The first step in preparing structures for shaking is to understand how buildings respond to ground motions- this is the field of study for earthquake and structural engineers. The buildup of pressure becomes unbearable and releases itself with a massive explosion. There are some interesting questions in terms of differences between floods and earthquakes.
Thus Macelwane Hall resonates at about 0. Tsunami has much smaller amplitude in the high seas, and a very long wavelength, often hundreds of kilometers long, so that they generally pass unnoticed at sea. Over 500 people died in the area affected by this slide. While an earthquake occurs only for a few seconds, the aftershocks can go on for days after that. This video is part of Dr. Shaping up Most people probably did not realize that the Earth has a bit of a weight problem.
Remarkably, the impact of the largest quake to hit New Zealand since 1931 was surprisingly minor. You hear of appalling stories how one place can be brought to devastation in a snap because of earthquakes. In areas where disasters like earthquakes are a possibility, rigid plans with no alternative solutions or contingencies are not likely to be successful in a major disaster event. Someone says, you are going to live in that house for 20 years. An oil refinery is on fire, and a vast area has been flooded by a tsunami. Animations illustrate how and why earthquakes happen, how mountains and valleys have formed as a result, how the ground will shake in large earthquakes, and why this shaking is so destructive to buildings.
The quake struck at a depth of 16. These faults occur due to the impact of geological forces. The March 11, 2011, earthquake and tsumani that affected eastern Japan is not included because the fatalities caused, about 15,000, are fewer than those resulting from the temblors listed below. Liquefaction can cause other problems as the soil loses it ability to resist shear and flows much like quick sand. Major earthquakes can cause rupturing of roads, gas lines, and water pipelines. There are a number of interesting issues that affect the way one evaluates the performance of mitigation measures. Its magnitude may be small or large.
The long-run effects calculated as a consequence of unanticipated disasters were far larger than estimates of immediate damage from these events. In summary: Earthquakes cause the earth's surface to move in waves. Human life requires immediate medical aid and reconstruction services. More than 830,000 people are estimated to have been killed. In southern Italy in 1909 more than 100,000 people perished in an earthquake that struck the region.