Richter magnitude figures which measure the energy released by a quake don't always convey the effects of an earthquake well. Apart from the difficulty of conveying the logarithmic relationships, as NicoleC indicated, the energy may be released close to the surface (very bad) or deep down (less bad), or in different rock formations (nice hard stuff better, sloppy Bay Area landfill very bad). It would be better if reports used Mercalli intensity figures, rather like the Beaufort Wind Scale, as they relate directly to the damage and visible and felt effects.

Richter information

Mercalli scale

Without having more details of the position of the two quakes, it would be hard to make comparisons. Looking at overflight images of the Iran area, it was interesting how much did still seem to be standing (though aftershocks will change that.) Also, much was made of a 2000 year old fort that has fallen. That suggests that Bam has not been an area much affected by quakes, and therefore less likely to have derived a safer vernacular architecture. The area is in the middle of Iran, and it is the edges where most quakes show up on maps.

Penny