Watch your (geological) language!
http://www.turkeytravelplanner.com/go/Istanbul/Sights/Bosphorus/
Can’t cut and paste this - but I agree with the earthquake scenario...
Given the area, entirely possible. It was there that Jerry Lee Lewis got the inspiration for the old classis, 'Whole Lotta Shakin Goin On'. You believe that dontcha??? Must be getting late...