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- 5 - <br />historic seismicity within 200 miles of the site and the presence of <br />• possible capable faults to the southwest and north of the site. <br /> Historic Seismicity: The epicenter location for reported earthquakes <br />within 200 miles of the site between 1880 and the present are shown on <br />Fig. 5. Zrie majority of these earthquakes were small and resulted in <br />no damage even near their epicenters. Eighteen earthquakes caused <br />damage in their epicentral reyions. These earthquakes are shown by <br />triangles on Fig. 5, and a list of damaging earthquakes is shown on <br />Table A. The majority of the damaging earthquakes occurred along the <br />north-trending intermountain seismic belt whid-i runs through central <br />Utah. It is likely that this seismic belt will be the site of future <br />moderate to large earthquakes; however, it is located about 180 miles <br />west of the site, and even if a large earthquake were to occur in this <br />region, ground shaking at the disposal site could not be very strong. <br />• A major earthquake located in the Intermountain Seismic Belt should <br />not cause peak ground accelerations at the site in excess of 0.048. <br />Numerous small earthquakes have occurred in the Rangely Oil <br />Field and have been attributed to fluid injections for secondary oil <br />recovery, Gibbs (1973). '17~ese earthquakes have been attributed to <br />decreases in stress rn small normal faults located in the oil field. <br />Epicenters for ten of the larger earthyuakes in this area are shown on <br />Fig. 5. The largest earthquake associated with the Rangely Oil Field <br />occurred on February 15, 1967 and had a magnitude of 4.5. Its <br />epicenter was located about 22 miles from the disposal site. Using <br />magnitude and peak acceleration attenuation correlations prepared by <br />Donovan and Bernstein (1978), it is estimated that the peak horiwntal <br />• <br />