Golestan-Ardebil Earthquake of 28 February 1997, Mw 6.1
Golestan-Ardebil Earthquake of 28 February 1997, Mw 6.1
On February 28, 1997, a devastating earthquake with magnitude Mw=6.1 occurred in the southwestern part of the Sareyn city in the Ardebil province. The epicentral coordinates of the earthquake was located in 33.6N and 45.7E. Based on CMT moment tensor solution, the causative fault plane could be either an E-W right lateral or a N-S left lateral strike slip fault, whereas the recognition of the causative fault plane is impossible due to the lack of a surface rupture and also large error in location of aftershocks. The calculated maximum dislocation was about 27 cm and the stress drop was estimated to be 149 bar. At least, 965 people were killed, more than 2000 injured, 36,000 were homeless, 12,000 houses damaged or destroyed and 160,000 livestock were killed in the Ardabil area of northwestern Iran. Severe damage was observed to roads, electrical power lines, communications and water distribution systems around Ardabil. Hospitals and other medical buildings were overflowing with patients as a result of the earthquake. More than 83 villages experienced some form of damage. 25 accelerographs have recorded this earthquake. The focal depth of this event was reported to be 15km. The peak horizontal acceleration (0.615g) is recorded in a hypocentral distance of 23Km. The capital city of Ardebil was located in a hypocentral distance of about 38km and the site condition was indicative for soft soils. The higher damages in Ardebil (about 40km hypocentral distance) could be related to the soft soil site conditions.
The most important worldwide earthquakes on this day
| Date | Time | Y | X | Depth | Mw | Region | Refrence |
| 1102/2/28 | 18 | 34.40 | 62.20 | – | 5.3 | Harat | Amb |
| 1102/2/28 | – | 35.00 | 62.10 | – | 6.1 | – | NOAA |
| 1915/2/28 | 18:59:12 | 23.359 | 123.492 | 20 | 7.3 | southwestern Ryukyu Islands, Japan | USGS |
| 1950/2/28 | 10:21:00 | 45.882 | 143.491 | 329 | 7.7 | Hokkaido, Japan region | USGS |
| 1969/2/28 | 2:40:32 | 36.033 | -10.613 | 10 | 7.8 | Azores-Cape St. Vincent Ridge | USGS |
| 1997/2/28 | 12:57:18 | 38.075 | 48.05 | 10 | 6.1 | Golestan-Ardebil | NEIC |
| 2006/2/28 | 7:31:3 | 28.18 | 56.76 | 18 | 5.9 | – | IIEES |