Characteristics of magnetic anomalies and subsurface structure constraints of Balapur fault in Kashmir basin, NW Himalaya

Abstract

The study used total magnetic intensity (TMI) data to evaluate the incidence and characteristics of the Balapur fault in the Kashmir basin, NW Himalaya. The ground magnetic surveys were carried out at ~25 m station spacing in various linear profiles and grids across the fault. The magnetic measurements external to the Earth were recorded after every minute to remove the diurnal variations. The convenient filtering and derivative techniques were applied to the TMI database to assess the strike and subsurface constraints of the Balapur Fault. The study shows a clear relationship between the magnetic minima's and the inferred Balapur fault. The strike of the fault is found ~100 km from SE-NW of the Kashmir basin and is associated with several fractures throughout its course. The analysis also recorded TMI susceptibilities at the northwest Balapur fault in the Baramulla region where fault branching has also taken place. The study suggests that the fault is tectonically active and may host a significant magnitude earthquake in the region. The study also indicates that the fault may have further extensions and needs more subsurface geophysical studies. Further, our study signifies the role of ground magnetic surveys in subsurface fault evaluations.