This research is to analyze a wealth of data from a successful seismic expedition to one of the largest, but least understood features of the earth, the Tibetan Plateau. This large, high and actively seismic area is a result of the collision of the Indian continent with Eurasia. Eleven broad-band PASSCAL stations were deployed in the Summer of 1991 for 12 months along a north-south road across the Tibetan Plateau from Llasa to Golmud. In spite of daunting logistical and physical difficulties, the PIs', in cooperation with Chinese scientists, are successfully operating the array and have in the first few months, begun the production of an historical data set. Several new analysis techniques including receiver function analysis, surface-wave analysis, and refraction analysis will be applied to the data which will be available to all scientists through the IRIS Data Center. This research is a component of the National Earthquake Hazard Reduction Program.