PALEOSEISMIC INDICATORS IN THE RUPTURE ZONE OF THE 1993 KILLARI (LATUR) EARTHQUAKE

The 1993 Killari (Latur) earthquake in Maharashtra has provided a rare example of surface rupture in the Precambrian shield, No historic sei smic events of comparable magnitude have been recorded in Killari. How ever, deep trenching in the 1993 rupture zone revealed deformational s tructures consisting of thrust sheets possibly related to previous fau lting. These structures indicate that the 1993 event was indeed preced ed by earthquakes in the recent geologic past. Our studies also indica ted an obsequent fault-line scarp, aligned with the current rupture zo ne. The morphological features in the area suggest mass removal of the upper part of the hanging wall, that is on the southwestern side of t he rupture, aided by the highly crushed nature of the rock and high ra te of weathering. Our observations imply a long recurrence interval of seismic events in the epicentral area of the 1993 earthquake.