Attenuation of intensities in the United States

Isoseismal maps for a number of earthquakes were analyzed to study the attenuation of intensities with distance for different regions of the United States. A graphical method for the estimation of an initial set of epicentral intensities, Io, from the intensity-distance plot for different earthquakes was used, thus avoiding the need to equate the maximum reported or mapped intensity with Io. The attenuation relations were derived by using an iterative least-squares fit procedure, wherein an initial approximate estimate of Io for each earthquake is successively improved. As a by-product, the analysis yielded improved estimates of Io for each earthquake. These Io values were used to derive empirical relations between felt area and epicentral intensities for different regions.

[1]  B. F. Howell,et al.  Attenuation of Modified Mercalli intensity with distance from the epicenter , 1975, Bulletin of the Seismological Society of America.

[2]  B. F. Howell.  Seismic regionalization in North America based on Average Regional Seismic Hazard Index , 1974, Bulletin of the Seismological Society of America.

[3]  W. K. Cloud.  Intensity distribution and strong-motion seismograph results, Nevada earthquakes of July 6, 1954, and August 23, 1954 , 1956 .

[4]  C. Allin Cornell,et al.  Seismic Risk Analysis of Boston , 1975 .

[5]  Indra N. Gupta,et al.  Spatial attenuation of intensities for central U.S. earthquakes , 1976, Bulletin of the Seismological Society of America.

[6]  U. S. Coast.  United States Earthquakes, 1938 , 1933 .

[7]  U. S. Coast,et al.  United States Earthquakes, 1960 , 1940 .

[8]  O. Nuttli,et al.  Magnitude-recurrence relation for central Mississippi Valley earthquakes , 1974, Bulletin of the Seismological Society of America.

[9]  United States earthquakes, 1966 , 1968 .

[10]  G. Bollinger.  Seismicity of the southeastern United States , 1973, Bulletin of the Seismological Society of America.

[11]  Robert B. Herrmann,et al.  The south-central Illinois earthquake of November 9, 1968: Macroseismic studies , 1970, Bulletin of the Seismological Society of America.

[12]  S. T. Algermissen,et al.  A probabilistic estimate of maximum acceleration in rock in the contiguous United States , 1976 .

[13]  W. E. Smith.  Earthquakes in Eastern Canada and adjacent areas 1954-1959 , 1964 .

[14]  John G. Anderson.  On the attenuation of Modified Mercalli Intensity with distance in the United States , 1978 .

[15]  O. Nuttli,et al.  The Mississippi Valley earthquakes of 1811 and 1812: Intesities, ground motion and magnitudes , 1973, Bulletin of the Seismological Society of America.

[16]  U. Chandra,et al.  Attenuation of intensities in Iran , 1979, Bulletin of the Seismological Society of America.

[17]  U. S. Coast.  United States Earthquakes 1942 , 1932 .

[18]  Robin K. McGuire,et al.  FORTRAN computer program for seismic risk analysis , 1976 .

[19]  Attenuation of Modified Mercalli Intensities With Distance for the United States East of 106° W , 1972 .