EARTHQUAKE FAULTING AND SEISMOTECTONICS OF EASTERN LUT AREA; AN OBSERVATION ON THE SEFIDABEH (۱۹۹۴) EARTHQUAKE FAULT

The Sefidabeh earthquake of ۲۳ February ۱۹۹۴, in eastern Lut area, near the Iran-Afghanestan borderline, is investigated in this paper in a seismotectonic point of view. The reactivation of a secondary structural trend (Sefidabeh fault) during the Sefidabeh quake with a compressional (reverse) /left lateral strike slip mechanism, was probably the end of a seismic gap in this region since ۷۳۴ A.D. The north-south trended Nehbandan fault system and the Harirud lineament have prevailed a righ-lateral shear system which has controlled the structures in eastern lut area (eastern Iran). The recent principal stress direction is find to be N۳۲-۵۱E and the Sefidabeh fault-lineament (N۴۶W) is settled as a secondary trend due to the East-Neh fault system. The principal stress direction due to the fundamental faulting (N۴۵E) is in accordance with the stress situation in the Sefidabeh main shock.