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The ambient noise analysis was performed at ten installed broadband seismic stations of the Eastern Dharwar Craton in Telangana state, India. We calculated the power spectral densities and their corresponding probability density functions, using different types of noise to assess the stations' performance. One year of continuous data from January 2021 to December 2021 was used for the analysis. The results suggest that the observed vertical noise levels are within the defined global noise limits for all stations. In the short-period band, the stations are dominated by cultural noise due to human activities, industrial machinery, automobile traffic, etc., which also causes a strong variation between daytime and night-time. At the long-period band, the vertical component lies above the new low-noise model (NLNM) and the horizontal components marginally overshoot the new high-noise model (NHNM) due to the tilt effect. An assessment of the noise variation was also performed during the partial lockdown due to COVID-19 in 2021 imposed by the Telangana state government in India, which revealed no significant variations in short-period noise levels. It may show the effect of remote installation away from cultural noise. Overall, our estimation suggests stability and validates the performance of all the installed stations of the Eastern Dharwar Craton in Telangana state. Research Highlights: In this study, we performed ambient noise analysis for ten broadband seismic stations of the Eastern Dharwar Craton, in Telangana state. We observed a significant diurnal variation as well as seasonal variation at all stations. We compared the noise variation during the period of partial lockdown in 2021 imposed by the Telangana state government in India and found no significant variations in short-period noise levels before and after partial lockdown. [ABSTRACT FROM AUTHOR]

To monitor seismicity, a 10-station broadband seismic network was deployed in the Hyderabad region by CSIR-NGRI, Hyderabad, India, during 2020–2021. The analysis of radial P- receiver functions (PRFs) using data from this network detects conversions from five major crustal and mantle discontinuities below the region. Our CCP stacking of radial PRFs also images the nature and geometry of these seismic discontinuities viz., Moho (increase in positive amplitude at 30–40 km depths), Hales discontinuity (increase in positive amplitude at 90–120 km depths), lithosphere-asthenosphere boundary (LAB) (increase in negative amplitude at 130–160 km depths), 410-km (increase in positive PRF amplitude at 410–440 km depths) and 660-km (increase in positive PRF amplitude at 620–660 km depths). Our modeling also reveals that the mean depth to the Moho, Hales discontinuity (H-D) and LAB below the study region are 36, 115 and 160 km, respectively, suggesting the absence of a thick cratonic root below the EDC. We interpret the H-D boundary (at 90–125 km depths) below the Hyderabad region as a lithologic boundary between upper mantle peridotite and eclogite resulted from the Archean subduction. We also model the differential time of the 410- and 660-km conversions, which is found to be 24 s at most of the stations that is the same as the theoretical differential time between these two phases according to the IASP91 global reference velocity model, indicating a typical cratonic behaviour of the EDC. However, a noticeable upward movement of the 410-km discontinuity and a slight downward movement of the 660-km discontinuity below the central part of the study region is also modelled that suggests a thickening of the Mantle transition zone, which could be attributed to the presence of probable imprints of the Archean subduction below the Hyderabad, EDC, India. [ABSTRACT FROM AUTHOR]