[J02-3] Recent large earthquakes III

[J02-3-03] Crustal deformation of the 2016 Kaikoura earthquake, New Zealand, revealed by ALOS-2

^○Yu Morishita, Tomokazu Kobayashi, Satoshi Fujiwara, Hiroshi Yarai (Geospatial Information Authority of Japan, Tsukuba, Japan)

The 2016 Kaikoura earthquake, New Zealand, occurred on 13 November 2016. We revealed the details of crustal deformation associated with the earthquake by ALOS-2 SAR data applying InSAR, a Pixel Offset method, and decomposition of these displacement data into vertical and horizontal components. Very large and extensive displacement was mainly detected around the Kekerengu Fault, the Jordan Thrust, the Hundalee Fault, and the Humps Fault Zone (e.g., more than 9 m uplift and horizontal shift around the Kekerengu Fault). We also constructed rectangular fault models with a uniform slip distribution using the 3D displacement data. The constructed fault models indicate that complicated fault motion occurred along both known active faults and also along unmapped faults. In addition to the large displacements, numerous linear discontinuities in the differential phase of InSAR images which may represent surface ruptures of several centimeters or larger were observed. These small-displacement linear surface ruptures may have been triggered by the main large fault slips.