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Near-field ground motion of the 2002 Denali fault, Alaska, earthquake recorded at pump station 10

W.L. Ellsworth·M. Çelebi·J.R. Evans·E.G. Jensen·R. Kayen·M.C. Metz·D.J. Nyman·J.W. Roddick·P. Spudich·C.D. Stephens
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Abstract

A free-field recording of the Denali fault earthquake was obtained by the Alyeska Pipeline Service Company 3 km from the surface rupture of the Denali fault. The instrument, part of the monitoring and control system for the trans-Alaska pipeline, was located at Pump Station 10, approximately 85 km east of the epicenter. After correction for the measured instrument response, we recover a seismogram that includes a permanent displacement of 3.0 m. The recorded ground motion has relatively low peak acceleration (0.36 g) and very high peak velocity (180 cm/s). Nonlinear soil response may have reduced the peak acceleration to this 0.36 g value. Accelerations in excess of 0.1 g lasted for 10 s, with the most intense motion occurring during a 1.5-s interval when the rupture passed the site. The low acceleration and high velocity observed near the fault in this earthquake agree with observations from other recent large-magnitude earthquakes. ?? 2004, Earthquake Engineering Research Institute.

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W.L. Ellsworth, M. Çelebi, J.R. Evans, E.G. Jensen, R. Kayen, M.C. Metz, D.J. Nyman, J.W. Roddick, P. Spudich, C.D. Stephens. 2004-08-01. Near-field ground motion of the 2002 Denali fault, Alaska, earthquake recorded at pump station 10. https://doi.org/10.1193/1.1778172

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