Present-Day Crustal Deformation in the Imphal Valley of Northeast India from Observations at A Newly Established Global Navigation Satellite System (GNSS) Station (2015–2024): Implications for India–Burma Plate Interactions
Laishram Sunil Singh *
Department of Geology, Waikhom Mani Girls` College, Thoubal, Okram, Manipur, India.
*Author to whom correspondence should be addressed.
Abstract
The Imphal Valley, situated within the Indo-Burmese Wedge of Northeast India, represents one of the most tectonically active regions along the India–Burma plate boundary. Despite its geodynamic significance, continuous geodetic observations from this area remain limited. In this study, present-day crustal deformation was investigated using long-term observations acquired from a permanent Global Navigation Satellite System (GNSS) station established at the Multi-Parametric Geophysical Observatory (MPGO), Imphal. Continuous data collected between 2015 and 2024 were processed using the GAMIT/GLOBK software package within the International Terrestrial Reference Frame (ITRF2014) to determine station coordinates and crustal velocities. The analysis indicates that the Imphal station (IMP1) moves at an absolute horizontal velocity of 36.3 ± 0.5 mm yr⁻¹ toward N55°E. When referenced to the stable Indian Plate, the station exhibits a residual velocity of approximately 16.7 mm yr⁻¹ toward N222°, indicating persistent southwestward motion. These results indicate that the Imphal Valley is undergoing active deformation associated with the ongoing convergence between the Indian Plate and the Burma microplate. The velocity estimates presented here provide new geodetic constraints on regional plate kinematics and contribute to a better understanding of deformation within the Indo-Burmese Wedge. Continuous GNSS monitoring is shown to be an effective approach for quantifying crustal motion and improving tectonic interpretations and seismic hazard assessment in Northeast India.
Keywords: Global Navigation Satellite System (GNSS), crustal deformation, Imphal Valley, Indo-Burmese Wedge, India–Burma plate boundary, Indian Plate-fixed reference frame, ITRF2014, plate kinematics, residual velocity, seismic hazard