黃石火山真的會爆發(fā)嗎-黃石火山活動監(jiān)測

1、真的會噴發(fā)嗎？真的會噴發(fā)嗎？WILL IT BLOW?黃石火山活動監(jiān)測Monitoring Yellowstones Volcanic ActivityThe Problem Congratulations! Youre a private consultant and you have just been awarded a $100,000 contract from a major developer. This developer would like to build a 3500 acre resort and golf course in Yellowstone National

2、 Park. Your task is to prepare a report advising the developer as to the most risk-free place in the park to build his resort.Where is Yellowstone National Park?Image from University of Utah College of Mines and Earth Sciences /ggcmpsem/UUSATRG/GPS/time_series.html andhttp:/v

3、/yvo/about/index.phpWhere is Yellowstone?Where is Yellowstone?Image from Bob Smith, University of Utah as accessed from Yellowstone Volcano Observatory /yvo/about/history/comparison.phpWhere is Yellowstone?KeyPark BoundaryGPS stationsMost recent caldera 600,0

4、00 years oldDomes within the caldera caused by intruding magmaMake a key to Make a key to color code your color code your mapmap5.5 square miles = 3500 acresWhere is Yellowstone? Add roads and cities to your map Remember that you need roads to get to your resortMonitoring Yellowstones Activity Volca

5、nic EruptionsYellowstone eruptions started 17 million years ago (mya)Leaving a path of large craters called calderas as the North American plate moved over a “hotspot” (kind of like Hawaii)Yellowstone is one of the largest and most active calderas in the worldImage from Smith, R. B., and Siegel, L.,

6、 2000, Windows into the Earth: The Geologic Story of Yellowstone and Grand Teton National Parks: New York, Oxford University Press, p. 242. accessed from Yellowstone Volcano Observatory /yvo/history.html#smith2000Monitoring Yellowstones Activity Volcanic EruptionsModern Calde

7、ra 600,000 yrs old“Ancient Yellowstones”2 mya1.3 mya6.5-4.3 mya10-7 mya10.5-8.6 mya12-10.5 mya15-13 mya16.5-15 myaHow often does the Yellowstone hot-spot appear to construct a new caldera?Monitoring Yellowstones Activity Volcanic EruptionsApproximately every 2 MILLION YEARS!How often does the Yellow

8、stone hot-spot appear to construct a new caldera?Ash from Yellowstones most recent caldera building event has been mapped in Iowa, Louisiana and California!Monitoring Yellowstones Activity Lava Flows Image from USGS Fact Sheet 2005-3024 “Steam Explosions, Earthquakes, and Volcanic EruptionsWhats in

9、Yellowstones Future?” /fs/2005/3024/There have been 30 lava flows since the modern caldera formedBetween 640-160,000 years ago (orange)Between 160-70,000 years ago (pink)Monitoring Yellowstones ActivityHydrothermal Explosions Yellowstone is home to more than a dozen large hydrothe

10、rmal-explosion craters -found between Norris Geyser Basin and Mammoth Hot Springs The largest hydrothermal-explosion crater in the world is located on the northern edge of Yellowstone Lake 1880s to 1890s Excelsior Geyser in Midway Geyser Basin experienced a series of explosions 1989 Porkchop Geyser

11、in Norris Geyser Basin explodedImage by Peaco (2001) Yellowstone Digital Slide File National Park Service /archive/yell/slidefile/thermalfeatures/thermalexplosions/Page.htmIndian Ponda Hydrothermal Explosion CraterMonitoring Yellowstones ActivityHydrothermal Explosions Image from US

12、GS Fact Sheet 2005-3024 “Steam Explosions, Earthquakes, and Volcanic EruptionsWhats in Yellowstones Future?” /fs/2005/3024/Label Hydrothermal Eruptions on your map(orange stars)Monitoring Yellowstones ActivityHydrothermal Activity Yellowstone has over 10,000 water and hydrothermal

13、 features Roads, lakes, and rivers are show waterfalls are blue dots thermal features are red dots Label regions of Hydrothermal Activity on your mapImage from Topoimagery “Making a Map: Mapping the Distribution of Yellowstone Water Resources” Monitoring Yellowstones ActivityVolcanic Gas Emissions V

14、olcanic gasses can be difficult to monitor however scientists can use other indicators 1897 Eight bears found dead near “Death Gulch” (southeast of the park boundary) from carbon dioxide (CO2) or hydrogen sulfide (H2S) poisoningThese gasses are heavier than air and tend to stay near the ground espec

15、ially on windless cold nights 2003 Several new fumaroles recorded in Norris Geyser BasinFumaroles are vents that release volcanic gasses 2004 Five bison found dead in the Norris Geyser Basin also attributed to CO2 or H2S poisoning Only one human has died due to gases in Yellowstone. CO2 is released

16、in small amounts from virtually all of Yellowstones hydrothermal features Label areas that are susceptible to volcanic gasses on your mapMonitoring Yellowstones ActivityEarthquakesHistorical Data Thousands of small earthquakes are recorded every year (called swarms) Most are too small to feel 3-4 ar

17、e strong enough to feel in the park Many of these earthquakes have nothing to do with the hotspot as they are related to stretching caused by plate tectonics Only 2 major earthquakes have been recorded 1959 7.5 Hebgen Lake earthquake 1975 6.5 Norris Geyser BasinMonitoring Yellowstones ActivityEarthq

18、uakesImage from Yellowstone Volcano Observatory /yvo/LvlMap.htmlLabel Earthquakes on your map(red stars)Monitoring Yellowstones ActivityEarthquakesHistorical Data The dots on this image are all the recorded earthquakes What patterns do you see? What regions have the least num

19、ber of earthquakes? You may want to highlight the regions with the least earthquakes on your mapImage from University of Utah: Seismicity of Yellowstone: /research/seismicity.htmlMonitoring Yellowstones ActivityEarthquakesReal-time data Recent earthquake activity (7

20、day) /req2webdir/recenteqs/Maps/Yellowstone.html Live seismograms /helicorder/yell_webi.htm Yellowstone Earthquake Epicenter Map Animation /maps/yellowstoneQuakes/index.html Find out information from the 2008 earthquake swar

21、m at Yellowstone lake /yvo/publications/2009/09swarm.php Find out information from the 2010 earthquake swarm at Madison Plateau /yvo/publications/2010/10swarm.php Are there any patterns to where earthquakes are occurring?Monitoring Yellowstones Activit

22、yGround DeformationHistorical Data Monitoring began in 1923 before GPS Scientists used ground equipment to survey until 1996 but they had to repeat the survey every year Picked a “straight line” from Lake Butte (east side of caldera) to Mount Washburn (north tip of caldera)Draw these locations on yo

23、ur mapMonitoring Yellowstones ActivityGround DeformationHistorical Data What part of Yellowstone is described in this graph? What patterns do you notice? Look at your map, which GPS stations would have current data for this area?Image from Yellowstone Volcano Observatory /yvo

24、/LvlData1923-1995.htmlMonitoring Yellowstones ActivityGround DeformationHistorical DataScientists can also collect ground deformation data using a satellite based instrument called INSAR (Interferometric Synthetic Aperture Radar)The center of the long rainbow pattern is where Yellowstone is deformin

25、g upward (inflating).The bulls-eye in the north west is where Yellowstone is deforming downward (deflating).Image from USGS, (2008) Recent ups and downs of Yellowstone Caldera. /yvo/publications/2007/upsanddowns.phpMonitoring Yellowstones ActivityGround DeformationReal-time D

26、ata Based Real-time GPS data from UNAVCO /edu_outreach/data.html Follow Student Worksheet GPS Part I instructions to plot data from the Yellowstone Data Set on a graphData points are an average for the entire year. If you would like to see instantaneous data, you can view time plots

27、for each of your chosen stations using the above link. Do you see the same trend in the GPS data as was in the leveling data? Can this trend be assumed for all of Yellowstone? Why might the GPS data be different from the Leveling data?Monitoring Yellowstones ActivityGround DeformationReal-time Data

28、Analyze GPS data from All of Yellowstone Follow Student Worksheet instructions “GPS part II” to plot data from Yellowstone Data Set on a graph Are there any patterns to your data? What might these patterns mean? Label regions on your map that are experiencing ground deformationMonitoring Yellowstone

29、s ActivityNow you are ready to write your report Follow the instructions on your worksheet Here are some points that you may want to consider How much land is needed for the resort Dont forget that the boundary of the caldera is a cliff Where are roads/ Can your proposed site be reached Topographic

30、map with roads /fs/fs100-03/images/yellowstone_fig2.jpg Can any of the hazards be mitigated What hazards are immediate dangers and what hazards occur every hundred thousand to million years or so Is there any other data you wish you hadSourcesAmerican Museum of Natural History (n.

31、d.) Science Bulletins: Yellowstone: Monitoring the Fire Below, “Signs of Restlessness” /earth/f/yellowstone.20060601/essays/86_print.phpChristensen, R. et. al. (2007) “Preliminary Assessment of Volcanic and Hydrothermal Hazards in Yellowstone National Park and Vicinity. “USGS. Open-file Report 2007-1071Dzurisin, D., Savage, J.C., and Fournier, R.O., 1990, Recent crustal subsidence at Yellowstone Caldera, Wy