Abstract:
High resolution aeromagnetic (HRAM) data collected recently over the Kutch Rift Basin have been analysed to look below the salt plains, grassland and sediments and to understand the Basin configuration of this seismically active region. The analysis has been able to identify several hitherto unknown dykes, sedimentary basins, faults and intrusive and throws light on the depositional history of the Deccan traps. The Banni Plains depict a ridge and depression structure and we identify aureole like structures within the Banni Plains which could possibly be related to hydrocarbon formations. We find that the epicenter of the Bhuj earthquake lies on the intersection of three subsurface faults and the faults are related to t he directional change of the compressional forces on either side of the Bhuj epicenter, as calculated by GPS measurements. The epicenter of the aftershocks are constrained to lie within and area demarcated by these three faults. Through the modeling of aeromagnetic data along a seismic reflection section passing through Bhuj and Anjar, we estimate the depth of the fault. The study brings out the importance of aeromagnetic data in study of regions with large surface cover and the important role of integrated geophysical studies.
