Heterogeneous lithosphere and the underlying mantle of the Indian subcontinent

► S-wave velocities in the uppermost mantle are very low in 3 regions. ► In the low-velocity regions mantle Vp/Vs ratio is anomalously high. ► Low Vp/Vs ratio in the upper mantle of the Himalaya is confirmed by new data. ► Unusual crustal structure is found in the eruptive center of the Deccan Traps. ► The 410-km discontinuity varies in depth in a range of 30 km.