The Deccan volcanic province (DVP) witnessed a massive outpouring of flood basalts of ∼2 million km³ volume, at ∼65 Ma, in less than a Myr. The volcanic eruption is concomitant with crustal extension, lithospheric thinning and magma influx beneath the major rift systems namely Cambay, Narmada, and Kutch. In this study, we investigate the anisotropic and isotropic variations within the crust and upper mantle beneath the northwestern DVP by estimating the shear wave velocity (V_SV, V_SH, and V_Soigt) and radial anisotropy (ξ_oigt) models using the Surface Wave Tomography technique. A joint inversion of the regionalized Rayleigh and Love wave group velocities is performed, using the genetic algorithm approach. Our results reveal different intracrustal layers, lid, and a low‐velocity zone (LVZ). This LVZ comprises of a uniform asthenospheric low‐velocity layer (LVL) of average V_SV 4.44 km/s and V_SH 4.47 km/s, and another LVL below, of average V_SV 4.45 km/s and V_SH 4.41 km/s. Furthermore, the LVZ represents a negative anomaly with reference to different global models (AK135, STW105, PREM, and S2.9EA). A negative ξ_oigt is observed in the LVZ, indicating dominance of vertical flow. This could be related to presence of partials melts, volatile materials and/or a thermal anomaly. We also identified the Moho (∼34–40 km) and lithosphere‐asthenosphere boundary (∼84–123 km). The low V_S values, negative ξ_oigt and a thin lithosphere (∼84 km) in the vicinity of Gulf of Cambay affirm the presence of a plume head beneath it, in concurrence with the hypothesis of Indian Plate‐Reunion plume interaction.

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