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Determining generic velocity and density models for crustal amplification calculations, with an update of the Boore and Joyner (1997) Generic Site Amplification for Graphic Site Amplification

David Boore
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Abstract

This short note contains two contributions related to deriving depth‐dependent velocity and density models for use in computing generic crustal amplifications. The first contribution is a method for interpolating two velocity profiles to obtain a third profile with a time‐averaged velocity to depth Z that is equal to a specified value (e.g., for shear‐wave velocity V S , for Z =30  m, in which the subscript S has been added to indicate that the average is for shear‐wave velocities). The second contribution is a procedure for obtaining densities from V S . The first contribution is used to extend and revise the Boore and Joyner (1997) generic rock V S model, for which , to a model with the more common . This new model is then used with the densities from the second contribution to compute crustal amplifications for a generic site with .

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David Boore. 2015-12-29. Determining generic velocity and density models for crustal amplification calculations, with an update of the Boore and Joyner (1997) Generic Site Amplification for Graphic Site Amplification. https://doi.org/10.1785/0120150229

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