The northeast (NE) India represents a complex geodynamics with an active seismicity, known as one of the major seismic potential zones of the world. The seismic deformation pattern beneath this region is disparate and is mostly controlled by complex tectonics and large geological structures surrounded by this region. It is well proved that the long extension of major geologic structures (mountain belts, folds and faults) contributes largely towards the deformation patterns beneath a particular region. This chapter presents deformation models for the lithospheric-scale deformation mechanism controlled by major geological structures present in and around the Shillong plateau, Assam Foredeep and the northeast Himalayan arc region. The shear wave splitting analysis at the closest proximity of these deep-rooted major faults prove that the lithospheric deformation patterns are strongly influenced and controlled by their geological alignments. Collisional tectonics resulted from the rapid and continuous convergence of the Indian plate beneath the Eurasian plate and vertical coherent deformation due to fault movements are the responsible mechanisms for lithospheric scale-deformations associated with the major faults in the Himalayan arc and southern Shillong regions. Contrary to this, the Absolute Plate Motion related strain due to the asthenosphere drag at the base of Indian lithosphere acts as a major source of anisotropy beneath the Assam Foredeep and the central Shillong region, where no influences from the shallow or crustal-scale structures could be attributed towards deformation mechanisms.