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at Depth (SAFOD), for probing and monitoring the San Andreas fault at seismogenic depths; (3) Plate Boundary Observatory (PBO), for measuring deformations of the western United States using strainmeters and ultraprecise geodesy of the Global Positioning System; and (4) Interferometric Synthetic Aperture Radar (InSAR) Initiative, for using satellite-based InSAR to map surface deformations, especially the deformation fields associated with active faults and volcanoes (<http://www.earthscope.org>).
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17.
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In the 1960s, studies of seismicity induced by reservoir loading (D. Simpson, W. Leith, and C. Scholz, Two types of reservoir-induced seismicity, Bull. Seis. Soc. Am., 78, 2025-2040, 1988) and injection of fluids into rock masses (J. Healy, W. Rubey, D. Griggs, and C.B. Raleigh, The Denver earthquakes, Colorado, USA, Science, 161, 1301-1310, 1968) stimulated speculations that similar methods might be adaptable to relieving tectonic stresses prior to large earthquakes. In 1969, a National Research Council report put forward the argument not only for earthquake prediction, but also for earthquake control: “Prevention or control of destructive earthquakes must rank as a major goal of seismology” (National Research Council, Seismology: Responsibilities and Requirements of a Growing Science, Part 1: Summary and Recommendations, National Academy Press, Washington, D.C., p. 15, 1969). This can-do attitude was quickly replaced by the recognition that the stresses and strains in the brittle crust are such complex functions of space and time and so poorly known that any program aimed at beneficial control would be expensive, ineffective, and potentially dangerous, especially in regions of high seismic activity.
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18.
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National Research Council, National Science Education Standards, National Academy Press, Washington, D.C., 262 pp., 1996.
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20.
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According to the Bureau of Labor Statistics, a bachelor’s degree in geology or geophysics is adequate for some entry-level jobs, but more job opportunities and better jobs with good advancement potential usually require at least a master’s degree. See U.S. Department of Labor, Occupational Outlook Handbook, 2000-2001 edition, Bulletin 2520, <http://www.bls.gov/oco/ocos050.htm>.
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