Myanmar, located on the eastern margin of the ongoing Indo-Eurasian collision system, has experienced a complex tectonic history. The region is characterized by the southward extrusion of the Shan-Thai plateau to the east and the highly oblique subduction of the India plate to the west. A large portion of the plate conversion is partitioned onto the nearly N-S-oriented Sagaing Fault (SF) running through the country. Due to the active tectonics in the region, Myanmar is threatened by a high level of seismic hazard. In addition, the economic (Yangon) and political (Naypyidaw) centres of the country are located along a seismic gap of the SF, which could rupture in a damaging earthquake in the near future. However, the earthquakes and velocity structure in the region are poorly known due to the lack of regional seismic observations. To better understand the neotectonics and provide a basis to prepare for the seismic hazard, we propose to build on the available broadband seismic network in and around Myanmar, aiming to address the following scientific questions:
1. What is the detailed lithospheric and basin velocity structure in Myanmar and its relationship to the geological process?
2. What is the velocity structure of the subducting slab beneath Myanmar and its relationship with intra-slab seismicity and geodynamic process?
3. What are the locking depth and fault zone structure of the SF, and their impacts on the seismic hazard?
4. What are the crustal and intra-slab seismicity and their implications for the seismic hazard?
Using the broadband seismic network we deployed in Myanmar, along with other available datasets, we have filled in several fundamental knowledge gaps in the region, which include proposing the first 3D community velocity model for the Myanmar region (Wang et al., 2019; Wu et al., 2020), a high-resolution local seismicity catalogue (Fadil et al., 2021; Chen et al., 2021), and a detailed case study of a Mw6.0 earthquake that occurred within the Bago-Yoma Range and poses a threat to the numerous dams built for irrigation (Fadil et al., 2020). We also collected comprehensive macro ground shaking and seismic data for the 2016 Mw6.7 intra-slab earthquake and produced the first detailed intensity map in Myanmar (Aung et al., 2019). Besides seismological investigations, the geodetic and geologic groups at EOS/ASE also investigate extensively in Myanmar, the collaboration between my group and the other tectonic (i.e. geodetic and geologic) groups at EOS has shown great advantages to make scientific findings (e.g. Wu et al., 2020; Wang et al., 2019).
- Earth Observatory of Singapore
Wang Xin, Institute of Geology and Geophysics, Chinese Academy of Sciences
Chen Meng, University of Electronic Science and Technology of China
Wenbo Wu, Department of Geoscience, Princeton University
Wang Yu, National Taiwan University
Huang Bor-Shouh, Institute of Earth Sciences, Academia Sinica, Taiwan
- A 3-D Shear Wave Velocity Model for Myanmar Region. Journal of Geophysical Research - Solid Earth. 124, 504-526. (2019).
- A comprehensive assessment of ground motions from two 2016 intra-slab earthquakes in Myanmar. Tectonophysics. 765, 146-160. (2019).
- Coulomb stress transfer and accumulation on the Sagaing Fault, Myanmar, over the past 110 years and its implications for seismic hazard. Geophysical Research Letters. 44(10), 4781-4789. (2017).