Determination of site amplification in the Los Angeles urban area from inversion of strong-motion records

S. C. Harmsen

doi:10.1785/bssa0870040866

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Determination of site amplification in the Los Angeles urban area from inversion of strong-motion records

S. C. Harmsen

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Abstract

The amplification of strong ground motion at sites in the greater Los Angeles, California, region is determined using the generalized-inverse method of Andrews (1986). Site-amplification estimates are determined at 281 strong-motion sites that provided horizontal-component accelerograms from the 1971 San Fernando, 1987 Whittier Narrows, 1991 Sierra Madre, or 1994 Northridge mainshocks. The estimates are determined relative to the spectral level recorded at a single reference site. In a second inversion, a source-site interaction term is added to Andrews's (1986) model to quantify the effect selected mainshock records have on site-amplification estimates. The source-site interaction term is applied to the San Fernando Valley sites' records of the Northridge earthquake and to three Los Angeles basin sites' records of the Whittier Narrows mainshock.

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Bulletin of the Seismological Society of America Article

Source-reported bounding extent: 33.359435728097196° to 34.58030693870565° latitude; -119.63191368282305° to -116.64363243282325° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

S. C. Harmsen. 1997-08-01. Determination of site amplification in the Los Angeles urban area from inversion of strong-motion records. https://doi.org/10.1785/bssa0870040866

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