Intraplate Earthquake and High Seismicity in the Western Margin of the Indian Lithospheric Plate: Insights From the Analysis of Stress–Strain Patterns in the Wagad Region of Kachchh, Gujarat, India

ABSTRACT

The Kachchh region of western India is one of the seismically active zones of the Indian lithospheric plate interior. The recurrence of high‐magnitude earthquakes in the past developed fractures which contributed to the neotectonic modification of the landscape of the region. Detailed analyses of fracture patterns and GPS velocity data were carried out to comprehend the stress–strain distribution in the Wagad uplift (WU) of the eastern Kachchh for the seismicity of the region. The results of the strain data reveal the presence of alternating zones of compression and extension and a zone of high shear strain in the eastern Kachchh. The intersections of lineaments form critical areas where significant earthquakes took place during the recent past. A regional fracture defining a strike of NNE–SSW (N11°) is found to possess an extremely high value of both extension and compression, which matches the critical orientation for earthquakes in the Eastern Kachchh. Intersections of a set of conjugate faults, ESE–WNW‐striking faults parallel to the South Wagad Fault and NNE–SSW‐trending transverse faults parallel to the Manfara Fault, have created regional zones of critical stress concentration in the WU. These critical fractures have been assessed to be the result of the regional compression from the Sulaiman Range acting on the Indian Plate.