And now, back to your regularly scheduled programming … A colleague of mine here at CIRES, geologist Roger Billham, has an excellent web site on the South Asia earthquake. Roger observes,

“How bad was it? If reports from the Kashmir epicentral region are confirmed, the number of fatalities exceeds 40,000 making it the most fatal earthquake ever to occur in the Indian subcontinent. The number of fatalities in an earthquake is linked to the vulnerability of local buildings, population density, and shaking intensity. In 1935 a Richter magnitude M7.5 strike-slip earthquake near the city of Quetta, the only large settlement in an otherwise sparsely populated region of Afghanistan, Pakistan and Baluchistan, resulted in an estimated 35,000 dead. The M7.8 Kangra earthquake in 1905 caused 20,000 fatalities, and the Mw=7.6 Bhuj 2001 earthquake 18,500.”

This figure which shows deaths versus earthquake magnitude is very interesting. Of it Roger notes,


“Deaths vs earthquake magnitude for earthquakes throughout the world 1900-2004 compared to the Kashmir 2005 earthquake. Although a simple relation between earthquake magnitude and the number of resulting deaths can be discerned (gray shading), the fatal consequences of large earthquakes depends more on their proximity to urban populations, the vulnerability of dwellings, and the time of day, than on the energy released. (fig. from Hough & Bilham,2005). The Sumatra/Andaman/Nicobar earthquake resulted in epicentral building collapse and damage, and huge loss of life along a thin but concentrated population on a coastal strip throughout the Indian ocean and Andaman sea.”

Lots more here.