Showing papers by "Ya-Ju Hsu published in 2016"
TL;DR: In this paper, the authors examined interseismic coupling of the Manila subduction zone and fault activity in the Luzon area using a block model constrained by GPS data collected from 1998 to 2015.
Abstract: We examine interseismic coupling of the Manila subduction zone and fault activity in the Luzon area using a block model constrained by GPS data collected from 1998 to 2015. Estimated long-term slip rates along the Manila subduction zone show a gradual southward decrease from 90-100 mm/yr at the northwest tip of Luzon to 65-80 mm/yr at the southern portion of the Manila Trench. We provide two block models (Models A and B) to illustrate possible realizations of coupling along the Manila Trench, which may be used to infer future earthquake rupture scenarios. Model A shows a low coupling ratio of 0.34 offshore western Luzon and continuous creeping on the plate interface at latitudes 18°-19°N. Model B includes the North Luzon Trough Fault and shows prevalent coupling on the plate interface with a coupling ratio of 0.48. Both models fit GPS velocities well though they have significantly different tectonic implications. The accumulated strain along the Manila subduction zone at latitudes 15°-19°N could be balanced by earthquakes with composite magnitudes of Mw 8.8-9.2 assuming recurrence intervals of 500-1000 years. GPS observations are consistent with full locking of the majority of active faults in Luzon to a depth of 20 km. Inferred moments of large inland earthquakes in Luzon fall in the range of Mw 6.9-7.6 assuming a recurrence interval of 100 years.
37 citations
TL;DR: In this paper, an elastic half-space model and GPS coseismic displacements were employed to invert for optimal fault geometry and coseistic slip distribution of the Mw 5.9 Wutai earthquake.
9 citations
TL;DR: In this paper, a continuous GPS network was deployed in the Western Solomon Islands to investigate the interseismic deformation and inferred coupling on the megathrust, and the authors discovered the former as a semi-permanent asperity and the latter as a potential megathyrust barrier.
Abstract: The Solomon megathrust along the Western Solomon Arc generated two megathrust earthquakes in the past decade (Mw 8.1 in 2007 and Mw 7.1 in 2010). To investigate the interseismic deformation and inferred coupling on the megathrust, we deployed the first continuous GPS network in the Western Solomon Islands. Our 2011-2014 GPS data and the back-slip inversion model show coupling ratio as high as 73% along the southeastern 2007 rupture segment, but only 10% on average along the segment of 2010 event. Based on the spatial distribution of coseismic slip, aftershock clusters, derived coupling pattern and paleo-geodetic records, we discovered the former as a semi-permanent asperity and the latter as a potential megathrust barrier. We propose that a characteristic earthquake of magnitude not less than Mw 8 will recur in an interval of 100 or more years by either single or doublet earthquake.
5 citations