Currently, our team is operating a seismic network consisting of 27 three-component broadband seismographs in the Ladakh Himalayan region (filled blue triangles in Fig. 1a). Further, we are going to install a 10-broadband station array in 2024 (filled green triangles in Fig. 1a). The violet filled squares mark the locations of geothermal spring sites (viz., Panamic, Chumtang, and Puga) and Tso Moriri lake.

Figure 1(a) Ladakh broadband seismic network

Furthermore, we are now upkeeping a broadband array consisting of 24 stations in the Himachal Pradesh (red filled inverted triangles in Fig. 1b).

Figure 1(b) Himachal Broadband seismic array

Based on the earthquake dataset would be obtained from the seismic network and array of broadband stations stated above, we want to conduct the following research projects:

• By analysing earthquake data collected from the Ladakh, Himachal, and Rajasthan broadband seismic networks/arrays, we will create a comprehensive model of the three-dimensional structure of the Earth's crust and mantle. This will be achieved by the use of P-receiver function (PRF) modelling, joint inversion of PRF and surface wave dispersion data, Conversion Common Point (CCP) as well as H-k Stacking of radial PRFs, and SKS splitting studies.

• The study focuses on studying the seismo-tectonics of the indicated seismically active locations in India. This will be accomplished by simulating the source characteristics and moment tensors of local and regional earthquakes.

• Modelling ground motions and site responses in seismically active regions of India for assessing seismic hazards. This will be backed by available estimates of near-surface shear wave velocity (Vs30m).

• Using teleseismic earthquake velocity tomography, we will try to outline the fine 3-D P-wave velocity structure all the way to the mantle depths beneath the Ladakh Himalaya.

Over the past ten years, our group has been responsible for operating seismic networks in the Kachchh rift zone, Singhbhum craton, Uttarakhand Himalaya, and Dharwar Craton. With the help of existing earthquake data from the past and present seismic networks of NGRI, we have already obtained finer crustal and lithospheric thickness models of the Uttarakhand Himalaya, Rajasthan, Singhbhum and Dharwar cratons through joint inversion of P-RFs and surface wave dispersion data, CCP as well as H-k Stacking of radial PRFs, and SKS splitting study. The significant findings from our past research investigations are mentioned in the following:

• Local earthquake seismic tomography was used to identify crustal mafic pluton-induced intraplate earthquakes and swarm activity in Kachchh (Gujarat), Saurashtra (Gujarat), and Palghar (Maharashtra), respectively.

• Detection of crustal and lithospheric thinning beneath the Kachchh rift zone indicates the presence of the 65 Ma Deccan Mantle Plume.

• Identified the varying thicknesses of the Earth's crust and lithosphere in the Dharwar Craton and Deccan Volcanic Province

• Our research shows that vertical tectonics dominated crustal uplift and subduction in the Eastern Indian Craton during the Archean epoch.

• Our research simulated three NNE-SSW trending lithospheric transverse structures to reduce rupture lengths and seismic risk in the Uttarakhand Himalaya.

• Our research on earthquake hazard evaluation in Kachchh (Gujarat) includes 3-D crustal Vp and Vs models, 3D ground motion models, predictive ground motion attenuation relations, pseudo acceleration spectra, site amplification, and sediment thickness maps. These data can be used to design earthquake-resistant buildings.

• Our research on upper mantle anisotropy and mantle transition zones in India has helped us better comprehend the geodynamic evolution of the Indian subcontinent.

• Our study of crustal anisotropy in Uttarakhand Himalaya and Kachchh (Gujarat) has greatly improved our understanding of crustal processes.

• Evaluated the site response, attenuation, and seismic source characteristics in the Uttarakhand Himalaya region.

• Identified impact-related deformation at 800 m depth in the Lonar crater in Maharashtra using shallow velocity imaging.

• Construction of 3-D models for seismic velocity and attenuation in the crust of the Koyna region, Maharashtra.

• Conducted research on background noise spectra, site response, and crustal velocity models in Hyderabad, located in the Eastern Dharwar Craton.