Acknowledgements
This paper is largely drawn from its larger perspective, the Indian Lithosphere, published in the Platinum Jubilee issue of the Indian Academy of Sciences. Data for the seismic studies described above were abstracted from seismograms generated by IRIS and the Chinese networks, PASSCAL experiments, INDEPTH II/III, and the Indian Institute of Astrophysics/Cambridge University, NGRI and IMD stations. Data analyses were performed by S.S. Rai, Supriyo Mitra, Keith Priestley, Charlotte Acton and Maggy Heintz. Deep appreciation is acknowledged of the unstinted support received from the Directors of the Indian Institute of Astrophysics, the CSIR Centre for Mathematical Modelling and Computer Simulation, the Physical Research Laboratory and the Indian Institute of geomagnetism at various stages of the work.