Paper presents the result’s of geomagnetic depth sounding (GDS) experiment carried out over restricted area of Valsad district, South Gujarat, which is experiencing swarm type of seismic activity since early 1986. The GDS experiment was designed to probe the sub-surface structures in and around the seismically active area which may prove helptul in identifying the likely cause of seismic activity. In this experiment an array of 12 fluxgate magnetometers were operated simultaneously to evaluate the pattern of induced currents associated with lateral discontinuities of electrical conductivity. Separation of observed transient geomagnetic variations into normal and anomalous parts and theír exami- nation in frequency-space domain suggests anomalous enhancement of east-west (Y) component of magnetic. field at stations bounding the seismically active area. Consistent with overall induction pattern, it is suggested that this anomalous behaviour is related to the channelling of induced currents through a pair of roughly NNW-SSE aligned conductive zones which may represent elongated fracture zones saturated with saline hot water. The role of these mapped structures in triggering earthquake swarm is not clear, but it is interesting that the seismic activity appears to be aligned along a line joining the diagonal ends of mapped elongated conductive zones. This geometric relations between structural features and epicentral distribution pattern is similar to those observed in many volcanic regions prone to earthquake swarms. To account the observation that anomalies in Y-component are not accompanied by any distinct anomaly in vertical component, it is suggested that the channelled currents complete their path by flowing vertically downward to conducting mantle. The vertical dikes which might have provided passage to the lava flows Deccan trap activity provide the right kind of structural configura- during tion for vertical leakage of currents. Following the hypothesis of Agrawal and Gaur (1270), it is conjectured that the present seismic activity may probably be related to the tectonic reorientation of dikes by shearing.