Research

Addressing the shortcomings of using GNSS data in geodetic modeling and exploring the interseismic deformation along the Himalayan plate boundary using ALOS-2 InSAR imagery. 

A work in progress!

We tried to address the discrepancies in the existing interseismic coupling map along the Himalayan plate boundary by using an updated compilation of GNSS data along with a suite of kinematic block models. Results show the MHT is highly coupled (>0.8) along its entire length. This translates to a high seismic hazard with a seismic moment accumulation of one Mw 8.7 megathrust earthquake per 100 years. Results further suggest that previously inferred low coupling zones along the plate interface are possible manifestations of block modeling artifacts, where the fault segments in the overriding plate control the megathrust slip distribution. This result highlights a strong need for better characterization of deforming structures in the overriding plate within the Himalayas and southern Tibetan plateau.

Read more about it here.

The status of active subduction along the Indo-Burmese Arc, where the Indian plate is subducting beneath the Sunda plate remains ambiguous due to inaccessible terrain and limited geodetic observations. This paper analyzes the available GNSS data from this region and characterizes the Euler rotation poles of the Indian and Sunda plates. The goal was to estimate the long-term plate motion and see how this motion is being distributed between these two plates. The long-term plate motion estimated to be ~37 mm/yr is partitioned among three major active units, namely, the Sagaing Fault (~18 mm/year), the Churachandpur‐Mao Fault (~17 mm/year), and the blind megathrust (~7 mm/year), from west to east of the IBA, respectively. The convergence estimate across the megathrust is significantly lower than the earlier estimates. The large scatter in data close to the up-dip edge of the blind megathrust is unable to resolve the creeping or accumulating strain, leading to uncertainty in the seismic hazard in this densely populated region.

 Read more about it here.

This study proposes that tectonic deformation along the Himalayan plate boundary is significantly influenced by the non-tectonic hydrological loading cycles over Southeast Asia. GNSS observations and satellite data from GRACE indicate higher transient displacements above the base of the seismogenic zone (i.e., mid-crustal ramp). This possibly indicate a role of changes in aseismic slip rate on the deep megathrust that may be controlled by seasonal hydrological loading.

Read more about it here.