Haiti earthquake one of the deadliest ever

I happened across a link to the US Geologic Service’s website today, which features a list of the most destructive and deadliest earthquakes in recorded history. The Haitian earthquake, with maybe 200,000 dead (reportedly, 75,000 have already been buried) easily qualifies.

In fact, it would go at about fifth on the list (a Chinese earthquake in 1920 and an Iranian earthquake in the 9th century also killed about 200,000 people).

What really astonished me was the one at the top of the list, though — on January 23, 1556, in Shensi, China, an earthquake with about magnitude 8 struck. That’s about 10 times the destructive force of last week’s earthquake in Haiti. The 16th century Chinese earthquake killed 830,000 people.

That’s 830,000 identified people. The website says “the unidentified was uncountable”:

The earthquake occurred near Huaxian, Shaanxi (formerly Shensi), China, about 50 miles (80 km) east-northeast of Xi’an, the capital of Shaanxi. … Damage extended as far away as Taiyuan, the capital of Shanxi (formerly Shansi) and about 270 miles (430 km) northeast of the epicenter. There are felt reports as far away as Liuyang in Hunan, more than 500 miles (800 km) away. Geological effects reported with this earthquake included ground fissures, uplift, subsidence, sandblows, liquefaction and landslides. Most towns in the damage area reported city walls collapsed, most to all houses collapsed and many of the towns reported ground fissures with water gushing out (ie. liquefaction and sandblows). Gu, et.al. says that “the identified death toll of soldiers and civilians was 830,000, and the unidentified was uncountable.”

Additional details from Gu, et.al.:

• In Huaxian, “city walls, temples, offices and civilian houses were demolished, without a single wall left standing…. The ground fissured and sunk. Water gushed out and formed canals. Sixty percent of the people (several tens of thousands were killed or injured.”
• In Weinan [15 miles (24 km) west of Huaxian], “city walls, temples, storehouses, offices and civilian houses collapsed totally…. In the city, the ground sunk for more than 3 meters. Fifty percent of the people were killed.”
• In Xi’an [one of China's major cities then as it is now], “city walls, storeyed buildings and terraces collapsed. Most temples were destroyed. More than half of the houses toppled down. Only 10-20 percent of the walls were left standing. The ground fissured crisscross. Thirty percent of the people were killed.”
• Even as far away as Taiyuan, “houses were destroyed in great numbers.”

Elsewhere on the USGS site, there’s a list of earthquakes so far this year. Obviously, the one in Haiti has had the largest effect — but did you know that the Solomon Islands were rocked by three quakes in early January, including one that was more powerful than the one in Haiti? That the San Francisco Bay was shaken? That Oklahoma City felt one?

And, more than 1,700 people died in 2009 from earthquakes — touching 15 countries on four continents. The USGS estimates that over a million earthquakes occur annually, though most go undetected because they are too remote or too weak. Still, they tally and post results of over 15,000 earthquakes every year. Whoa. That’s an average of 40 a day.

I’m slightly curious — do you think earthquakes are more likely to kill people in modern times, given that there are many more people living on earth, and we tend live in higher-density environments? Or are they less likely to kill people, given that many deadly earthquake zones have specific building codes, plus we have rapid-response disaster aid capacity?