The DBZ (Dasht-e-Bayaz-Zirkuh) cluster is based on several sequences of strong earthquakes along the Dasht-e-Bayaz and Abiz faults in eastern Iran, including the the Dasht-e-Bayaz earthquake (Mw 7.1) on August 31, 1968, the Mw 6.3 Ferdows event on September 1, 1968, the Ms 6.2 Qayen event on November 7, 1976, the Mw 6.5 Boznabad event on January 16, 1979, the Mw 6.6 Korizon/Ghaenat event on November 14, 1979, the Mw 7.1 Khuli-Boniabad event on November 27, 1979, the Mw 5.9 Kalat-e-Shur event on December 7, 1979 and the Mw 7.3 Zirkuh/Ardekul/Ghaen-Birjand event on May 10, 1997. Calibration is greatly aided by arrival time readings from the Khorasan Network (Ferdowsi University). A.R. Ghods repicked many of the arrival times from Iranian networks, including S-P data from the INSM network of accelerometers (BHRC). Focal depths of only 2 events are constrained by direct arrivals at near distances from temporary station deployments and S-P picks, and 21 events are constrained by local-distance readings. Focal depths of 25 older events are set by using depth phases. The remaining events are held at a default depth of 12 km. Further information about this cluster is contained in Walker et al (2011), Insights into the 1968–1997 Dasht-e-Bayaz and Zirkuh earthquake sequences, eastern Iran, from calibrated relocations, InSAR and high-resolution satellite imagery.
Number of events: 94
Calibration type: direct calibration using data to 1.2 degrees; hypocentroid calibration level = 1.8 km
Epicentral calibration range: 2 - 6 km
Date range: 19680831 - 20171114
Latitude range: 32.495 - 34.203
Longitude range: 58.180 - 60.307
Depth range: 5.0 - 22.0
Magnitude range: 3.4 - 7.3