Marine Roger
The earthquake cycle of the Chi-Chi event in the Tapei Basin.
Email: m.roger2@ncl.ac.uk
Supervisors
Areas of research
Project description
Earthquakes are major natural hazards. They threaten the population, especially where the demography is increasing. Precise monitoring of the deformation and estimation of the risk are essential. This investigation is based on earth observations complementary to each other. It will study surface deformation and an efficient way to understand and detect the different phases of the earthquake cycle.
We focus on the central-western part of Taiwan. This is a high-risk seismic area located at the collision boundary between the Philippine Sea plates and the Eurasian plate.
I will study in its entirety the earthquake cycle of the Chi-Chi event that struck the Taipei Basin in 1999 (Mw=7.6). The event was due to the reactivation of the Chelungpu thrust fault.
First, I will revisit the modelling of the coseismic phase to achieve a better understanding of the Chelungpu fault. I will present an improved methodology showing the complementarity of earth observation. I will also show the necessity of determining precise weighting between the datasets and a precise design of the fault, thanks to an improved geodetic inversion package.
The second part is the inter- and post-seismic deformation study to better understand the actual seismic risk. I will build time series showing the deformation of a few years before the event and the 20 years since it happened using GNSS data, C and L bands satellite images, and optical images.
Finally, a design of the seismic cycle of the Chi-Chi earthquake will be done. This will assess the deformation state of the Chelungpu fault. It will also estimate the possible consequences that a similar event in this area would be.
My thesis part of the Dragon 4 project funded by STFC and ESA.