REASSESSMENT OF EARTHQUAKE HAZARD BASED ON A FAULT-BEND FOLD MODEL OFTHE HIMALAYAN PLATE-BOUNDARY FAULT

At least three great earthquakes of M greater than or equal to 8 have ruptured the plate-boundary megathrust between India and the Himalaya in the last century, The central Himalaya moves southward as a fault-b end fold at 15 mm/yr or more by infrequent earthquakes that nucleate o n the highly-seismic ramp beneath the Himalaya and rupture southward a long a thrust flat to the range front, There is a consensus that futur e great earthquakes will strike the Himalayan front, with the next ear thquakes most likely in the 20th-century seismic gaps in Western Nepal , Kumaon, and Jammu-Kashmir, Because of the great increases in populat ion in these regions, losses in the next great earthquake are expected to be catastrophic. A realistic earthquake probability forecast requi res establishment of a GPS array in the northwest Himalaya to establis h slip rates on the plate-boundary fault and palaeoseismological inves tigations at the Himalayan front and adjacent Ganga plains to establis h earthquake recurrence intervals on individual segments of the fault.