Super typhoon shoved supersized boulder

Haiyan gave momentum to most massive rock ever seen moved by a storm

giant boulder

STRONG STORM  Tsunami-like waves generated by Typhoon Haiyan pushed around this giant boulder, which weighs roughly 180 metric tons.

M. Engel

SAN FRANCISCO — When Typhoon Haiyan made landfall in the Philippines in November 2013, its waves shoved a boulder weighing more than 25 adult African elephants. The boulder is the most massive known rock shifted by a storm, geoscientist Max Engel of the University of Cologne in Germany reported December 16 at the American Geophysical Union’s fall meeting.

Engel and colleagues initially thought there was a language barrier when a local fisherman told them that the 9-meter-wide, 180-metric-ton rock moved during the storm. Comparing satellite photos taken before and after the storm, the researchers found that the boulder traveled about 45 meters along a beach.

Based on videos recorded during the storm, the researchers think the typhoon created protracted tsunami-like waves that pushed the hefty rock. The observations suggest that other boulder movements that scientists had associated with tsunamis might actually have been caused by superstorms, Engel said.