Special Session: Urban Liquefaction and Lateral Spread Investigations and Mapping
Type: Oral
Day: 5/15/2018
Time: 2:15 PM
Room: Hibiscus A
Abstract
Earthquake triggered liquefaction and lateral spreading was widespread in Canterbury, New Zealand (NZ) during the 2010-2012 Canterbury Earthquake Sequence (CES) and led to ~$20 Billion NZD of damage. Although the causes and timing of liquefaction during the CES are well known, the geological controls on lateral spreading are more poorly- understood. We undertook a multidisciplinary investigation funded by the National Science Foundation (NSF) and explored lateral spreading in Christchurch during the CES using image differencing displacement maps, field mapping, shear wave velocity profiles, boreholes and cone penetration (CPT) soundings, and paleoseismic trenching with radiocarbon dating. Preliminary results suggest that cumulative displacements from the CES are less than those observed in our trench along faults and index beds in the subsurface, and along a key down-dropped soil, when combined with clear paleoliquefaction at the site (e.g. faulted pre- CES sand boils) suggest at least one major pre-CES lateral spreading event here. The results of this mapping with aid us with mapping liquefaction and lateral spreading globally.
Author(s):
De Pascale G. P. Department of Geology - University of Chile
Bachhuber J. Pacific Gas and Electric
Rathje E. M. University of Texas
Contemporary and Paleoliquefaction-Induced Lateral Spreading Mapping in Christchurch, New Zealand
Category
Urban Liquefaction and Lateral Spread Investigations and Mapping