Vengala Pavan Kumar, Bandari Naresh, Vaska Lokesh, Gudapati Suresh, Dakuri Srinivas, Mandadi Shekar, Raman Vijayaraghavan, Prakash Kumar
Abstract On 4 December 2024, a magnitude of 5.0 ML earthquake occurred in the Mulugu district of Telangana, within the Godavari graben—a significant rift structure in the Eastern Dharwar Craton (EDC), a region known for infrequent but impactful intraplate seismicity. This study investigates the source characteristics and focal mechanism of the event using broadband waveform data recorded by the CSIR–National Geophysical Research Institute seismic network across the EDC and surrounding areas. The Godavari graben has a well-recorded seismic history, with 297 earthquakes recorded between 1969 and 2023, ranging in magnitude from 0.8 to 5.7 ML (National Geophysical Research Institute [NGRI], 2017). Time-domain moment tensor inversion revealed a predominantly strike-slip focal mechanism, with a best-fitting solution indicating a focal depth of 10 km and a seismic moment of 1.40×1016 N·m (Mw 4.7). The orientation of one of the nodal planes is consistent with rupture along the Godavari Valley fault, a major northwest–southeast-trending structure reactivated under the prevailing compressive stress regime. Spectral analysis using the SourceSpec module provided key source parameters, including a weighted moment magnitude of Mw 4.90 ± 0.25, a corner frequency of 3.473 Hz, and a relatively high stress drop typical of compact, high-energy intraplate ruptures in strong, fractured crystalline crust. The Mulugu earthquake shares similar characteristics with past events in the region, notably the 1969 M 5.7 Bhadrachalam earthquake, which also exhibited strike-slip faulting under northeast–southwest compression. This recurring faulting style highlights the persistent influence of inherited rift structures and ongoing basement fault reactivation.