As with the earlier earthquakes, Tuesday's relieved stress to other parts of the North Anatolian fault. Reuters contributed to this report. Magnitude Downgraded Scientists are reassessing the characteristics of Tuesday's earthquake, with the magnitude now downgraded by nearly half a magnitude point below initial estimates. Initial reports pegged the quake at magnitude 7.8. But the head of Istanbul's Kandilli Observatory, Ahmet Mete Isikara, set the magnitude Wednesday at 7.4.
American geologists concur with the latest figure.
That would make the quake along the North Anatolian fault a significant event, but not among the most powerful of the century. I wouldn't be surprised if it continued to change by a tenth or two-tenths of a magnitude point. The higher magnitude reported in the hours immediately following Tuesday's quake reflected measurements from a small number of monitoring stations around the world that were recording a single type of seismic wave from the event. The revised magnitude is the product of a computer analysis of the entire seismic spectrum, scientists said. It's stronger and weaker in different directions, depending on the orientation of the fault.