Mapping Depth to Bedrock, Shear Stiffness, and Fundamental Site Period at CentrePort, Wellington, Using Surface‐Wave Methods: Implications for Local Seismic Site Amplification

Research Article| May 08, 2018 Mapping Depth to Bedrock, Shear Stiffness, and Fundamental Site Period at CentrePort, Wellington, Using Surface‐Wave Methods: Implications for Local Seismic Site Amplification Joseph Vantassel; Joseph Vantassel aThe University of Texas at Austin, 301 E. Dean Keeton Stop C1792, Austin, Texas 78712, jvantassel@utexas.edu Search for other works by this author on: GSW Google Scholar Brady Cox; Brady Cox aThe University of Texas at Austin, 301 E. Dean Keeton Stop C1792, Austin, Texas 78712, jvantassel@utexas.edu Search for other works by this author on: GSW Google Scholar Liam Wotherspoon; Liam Wotherspoon bDepartment of Civil and Environmental Engineering, University of Auckland, Engineering Block 1 ‐ Building 401, 20 Symonds Street, Auckland 1010, New Zealand Search for other works by this author on: GSW Google Scholar Andrew Stolte Andrew Stolte aThe University of Texas at Austin, 301 E. Dean Keeton Stop C1792, Austin, Texas 78712, jvantassel@utexas.edu Search for other works by this author on: GSW Google Scholar Author and Article Information Joseph Vantassel aThe University of Texas at Austin, 301 E. Dean Keeton Stop C1792, Austin, Texas 78712, jvantassel@utexas.edu Brady Cox aThe University of Texas at Austin, 301 E. Dean Keeton Stop C1792, Austin, Texas 78712, jvantassel@utexas.edu Liam Wotherspoon bDepartment of Civil and Environmental Engineering, University of Auckland, Engineering Block 1 ‐ Building 401, 20 Symonds Street, Auckland 1010, New Zealand Andrew Stolte aThe University of Texas at Austin, 301 E. Dean Keeton Stop C1792, Austin, Texas 78712, jvantassel@utexas.edu Publisher: Seismological Society of America First Online: 08 May 2018 Online Issn: 1943-3573 Print Issn: 0037-1106 © Seismological Society of America Bulletin of the Seismological Society of America (2018) 108 (3B): 1709–1721. https://doi.org/10.1785/0120170287 Article history First Online: 08 May 2018 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Joseph Vantassel, Brady Cox, Liam Wotherspoon, Andrew Stolte; Mapping Depth to Bedrock, Shear Stiffness, and Fundamental Site Period at CentrePort, Wellington, Using Surface‐Wave Methods: Implications for Local Seismic Site Amplification. Bulletin of the Seismological Society of America 2018;; 108 (3B): 1709–1721. doi: https://doi.org/10.1785/0120170287 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of the Seismological Society of America Search Advanced Search Abstract Wellington's port (CentrePort) experienced significant damage from the Mw 7.8 Kaikōura earthquake as a result of soil liquefaction, lateral spreading, and shaking‐induced damage to structures. To investigate these ill effects and propose mitigation measures to prevent similar damage in future earthquakes, there was a need to quantify the variations in the depth to bedrock, shear stiffness, and fundamental site period (⁠T0⁠) across the port. To characterize T0 and develop shear‐wave velocity (⁠VS⁠) profiles for use in seismic site‐response analyses, horizontal‐to‐vertical (H/V) spectral ratio (HVSR) measurements and active‐source and passive‐wavefield surface‐wave testing (i.e., multichannel analysis of surface wave [MASW] and microtremor array measurements [MAM], respectively) were performed across the port. A site‐period map developed from 114 HVSR measurements indicates several areas of rapidly changing, complex subsurface structure. Deep (200+ m) VS profiles developed at six reference locations across the port were used to estimate the depth to soft (⁠VS>760 m/s⁠) and hard (⁠VS>1500 m/s⁠) rock. T0 estimates from HVSR measurements (⁠T0_H/V⁠) at the six reference locations are shown to be related to the depth of hard rock, based on linear viscoelastic transfer functions calculated from VS profiles truncated at several depths. T0_H/V measurements at two ground‐motion stations near the port are also shown to be in reasonably good agreement with predominant periods of maximum spectral amplification recorded during both the 2016 Kaikōura and 2013 Cook Strait earthquakes, despite that these sites were also being affected by soil nonlinearity and potential 3D basin‐edge effects. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.