Atkinson and Boore Attenuation

In this example, you can calculate horizontal peak ground acceleration and the psuedoacceleration spectrum at a Cascadia Subduction zone site using attenuation relationships by Atkinson and Boore, 1997. The relationships are for rock sites only. Note that the site-to-fault distance is the hypocentral distance and the relationship is valid over the range of 10 to 400 km only. The valid range of magnitudes is 4 < Mw < 9.5. Links to tables of coefficients can be found in Appendix A. Interactive examples for all attenuation relationships can be found in Attenuate©.

Ground motion parameter:

Enter the model parameters you wish to use:

Site to fault distance (km):

Moment magnitude (Mw):

Period (s)
Ln median
median + s

PGA (g)

PGV (cm/s)
Sa (g)

modify spectrum
to attenuate©

Copyright 1999 Janise Rodgers, Pacific Earthquake Engineering Research Center, University of California, Berkeley.