LUMINESCENCE CHRONOLOGY OF SEISMITES AT SUMDO (SPITI VALLEY) NEAR KAURIK-CHANGO FAULT, NORTHWESTERN HIMALAYA

Abstract

Soft sediment deformation structures (seismites) observed at eight stratigraphic levels in fluvio-lacustrine sediments exposed in the Sumdo area of lower Spiti valley, Himachal Pradesh, India have been interpreted to represent eight paleoearthquakes of magnitude > 6.5 on the Richter scale. We present the first attempt to date seismites using luminescence dating techniques. The infrared stimulated lumine-scence ages range from 26 ka to 90 ka in samples from four seismites that were investigated. These ages suggest that the activation of Kaurik-Chango Fault and the seismic activity in the region dates back at least to the Late-Pleistocene.