Tsunami lab - Natural Disasters and Catastrophes Professor Cole PDF

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Natural Disasters and Catastrophes with Professor Cole Tsunami Lab from an A student...

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The Boxing Day Tsunami The Boxing Day Tsunami occurred in the Indian Ocean on December 26, 2004. In this exercise, you will explore the causes and effects of this event. In order to answer the following questions, you will need to open the Boxing Day Tsunami KMZ file in Google Earth. Be sure to specify the units for all distances, velocities, and times. 1. What were the latitude, longitude, magnitude, and depth of the source event for the tsunami? Latitude = 3.3, Longitude = 95.98, Magnitude = 9, Depth = 30 2. What was the closest country to the source event? Use the data in the Countries where Deaths Occurred folder to find out. Expand the folder. How many deaths occurred in that country as a result of the tsunami? Indonesia; 165,659 deaths 3. What country in which deaths occurred was farthest from the source event? About how far was it? How many deaths occurred there? Kenya, 1 death, about 6200km from the source 4. Make the Earth’s Tectonic Plates folder visible. This data is from the United States Geological Survey. What types of plate boundaries are represented by this data? Describe the interaction that occurs between the plates along the first three of the types of boundaries listed in the legend. What two types of plate boundaries are closest to the location of the source event? Divergent, Transform, Convergent, and Undefined. Divergent: Plates moving away from each other Convergent: Plates moving towards each other, usually results in subducted plate Transform: Plates move past each other Transform & Convergent boundaries are closest to the source event. 5. Make the folder that is entitled Seismic Events, Dec 25 to 31, 2004 visible. Where did most of the seismic events represented in this folder occur? How do these events relate to the source event? The seismic events in this folder occur along plate boundaries, with most occurring Northwest of the Indonesian island of Sumatra, between convergent and transform plate boundaries. These seismic events are recorded waves that radiate out from the “source event”, the focus of the EQ, in sequences and make the ground vibrate.

6. What types of plate boundaries are associated with the clusters of seismic events that occurred near Alaska and along the western coast of South America during the period December 25 to December 31, 2004? Convergent boundaries

7. According the Tectonic Summary in the USGS report on the event, Magnitude 9.1 - OFF THE WEST COAST OF NORTHERN SUMATRA, what was the cause of the seismic event that triggered the tsunami? The seismic event was “caused by the release of stresses that develop as the India plate subducts beneath the overriding Burma plate,” a phenomenon that occurs along convergent plate boundaries. 8. Watch the visualization from Kenji Satake at the Active Fault Research Center in Tsukuba, Japan, that is linked from the Carleton College Science Education Resource Center’s Tsunami Visualizations page. Also watch the NOAA visualization that tracks the tsunami waves until they reach the East African coast of Somalia and the NOAA and the rerun of the model that generated a world-wide picture of the wave's propagation.. What happens to the waves as they reach islands and as they enter straits that are narrower and shallower than the open ocean? The waves’ wavelengths become much shorter, the height of the waves increase, and the speed of the waves decreases.

9. Open the NGDC Wave Travel Time Overlay in Google Earth. This overlay documents the travel time of the waves from the location of the source event. Each line represents an hour of travel time. Bold lines mark 5-hour intervals. a) How long did it take the waves to reach Mozambique? What was their average velocity along the route that they took? About 10 hours; ~6200km/10hrs = avg velocity of 620km/hr b) How long did it take the waves to reach Cambodia? How did the velocity of the waves change as they proceeded from the source location to Cambodia? Why did this happen? About 22 hours, the velocity of the waves changed as they had been absorbed in part through the other land masses and ocean they travelled through, slowing down.

10. Make the Runups, Distances, and Times folder visible and highlight it. If the time slider appears in the upper right corner of the Google Earth 3D Viewer, expand it to its full range. What were the tsunami runup heights and travel times for each of the following places?



Beach labeled “South of Sibolga, Indonesia”

Max runup height = 1.5 m, Dist from source = 364km 

The Eva Hotel, which is northeast of Tangalla, Sri Lanka

7.5m; 1710km 

Cape May, New Jersey

0.13m; 15,229km; 32 hr 36 min travel time 11. Link to the Pacific Northwest Seismic Network’s January, 1700 Cascadia Subduction Zone earthquake and tsunami page. Please follow the links on that page, and describe the evidence for the “Great Quake of 1700”? “Page not found” comes up and the only other information I could find on this website had to do with the Native Americans passing stories about events from generation to generation. 12. Look at the before and after photos for the tsunami that are linked from the Carleton College Science Education Resource Center’s Tsunami Visualizations page. Why do people live and work along the shoreline even though it subjects them to the danger of tsunami waves? What adaptations to this threat would it be practical to implement? People still live and work along the shoreline because tsunamis are unpredictable and may not even happen in one person’s lifetime living along a particular coast. Coasts are ideal places to live due mainly to easy access to resources, including ease of transportation. It would be practical to implement housing structures that would not be completely obliterated during a tsunami, for example better, perhaps more water and pressure-resistant houses with firm foundations. Early warning systems that gather data out in the ocean would also be of positive use so that residents could evacuate the area before the tsunami hits....