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S U M M A R YCrustal structure across the India-Asia collision zone (Tidding Suture) in the northeast Himalaya bounded by the Eastern Himalayan Syntaxis (EHS) is investigated using the P-wave receiver function (RF) method. The analysed data included three-component waveforms of teleseismic earthquakes recorded by a linear array of 11 broad-band seismic stations. The RFs and inverted shear wave velocity models reveal azimuthally varying crustal structure. The RFs for earthquakes from the northeast back azimuths are conspicuous by absence of P-to-S converted phase at the Moho discontinuity. Inverted velocity model ascribe this to absence of the typical step velocity jump at the Moho in a narrow section of the EHS bordering the indenting Indian Plate and pierced by travelling waves. In contrast, teleseismic waves arriving from southeast back azimuth sample different litho-tectonic blocks of the Himalayan collision zone and inverted models show northeast dipping Moho across the Tidding Suture. Compared to an overall thickness of >70 km in the northwest and central Himalaya, the crust across the Tidding Suture is only about 55 km thick. This is attributed to a slower rate of convergence in this part of the collision zone. The Moho structure beneath Indian Plate and southeastern Tibetan Plateau reveal opposite dip directions with their colliding margin placed just east of the Walong Thrust. The inverted shear wave velocity models show evidence of intracrustal low-velocity layer whose strength varies across the Tidding Suture. The magnitude of velocity reduction beneath Lohit Plutonic Complex (Trans Himalaya) favour partial melt as a possible mechanism whereas south of the Tidding Suture, where velocity reduction is comparatively less, fluids generated by dehydration reactions appear to be the source for velocity reduction.

Crustal configuration beneath the Satluj valley region of the northwest Himalaya has been studied with the help of receiver function analysis of teleseismic earthquakes recorded by 18 broadband seismological stations. These stations were located on diverse geotectonic units from the Himalayan foreland basin in the south to the Tethyan Himalaya (TH) in the north. A gentle north dipping structure of the Main Himalayan Thrust (MHT) is imaged between the Sub and Higher Himalaya in contrast to the reported ramp structure of the MHT beneath the Garhwal and Nepal Himalaya. The ramp structure is, however, identified further north, beyond the South Tibetan Detachment in Satluj valley. The depth of the MHT varies from ~16 to 27 km across the Sub, Lesser, and Higher Himalaya, and it increases to ~38 km beneath the TH forming a ramp. This is significantly a different structure of the MHT beneath the Satluj valley, which is attributed to the effect of underthrusting Delhi‐Hardwar Ridge, a transverse structure to the Himalayan arc. Conspicuously, no strong or large earthquake is observed during 1964–2015 in this segment of the Himalayan Seismic Belt. The RF modeling, on the other hand, shows ~44 km crustal thickness beneath the Himalayan Frontal Thrust (HFT), and it gradually increases to ~62 km beneath the TH. Low shear wave velocity (~0.8–1.8 km s−1) is observed in the uppermost 3–4 km of the crust beneath the stations near the HFT, which may be the effect of the sedimentary column of the Indo‐Gangetic Plain.