This paper discusses the stress field in the Himalayan collision zone of India and Nepal, based on analyses of P axes of active faulting. Consistent thrusting or reverse faulting is predominant in the East Himalayan Front, indicating near-horizontal P axes in the N-S direction. In the Nepai Himalaya, north-dipping normal faulting as well as thrusting along E-W to NW faults are taking place close to each other. P axes of normal faulting are more or less perpendicular to the main thrust plane. This type of fault-normal compression may be due to the extremely low shear strength of the major boundary faults. In the western Himalayas including west Nepal, P axes deduced from reverse faulting in the foot-hill zone are NE-SW, inconsistent to the relative motion of the two plates. Right-lateral faulting along the NW-SE extending right-lateral stnke-slip transcurrent faults in the Himalayan range are newly found characteristic features, and the extremely low shear strength of these transcurrent faults and slightly oblique relative motion between the two plates, may be the cause of the fault-normal compression in the Western Himalayan Front.
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