Seismic echoes

Reverberations of a powerful temblor in southwestern

Mexico on Sept. 19 caused water to slosh against the surrounding limestone rock 1,500 miles away in a Death Valley National Park pool just a few minutes later. Experts call the phenomenon a “desert tsunami.” It also has been caused by strong quakes as far away as Japan, Indonesia and Chile. “It depends on the depth, magnitude and location around the world,” said National Park Service aquatic ecologist Kevin Wilson. He said the waves from the Mexican quake lasted about 30 minutes.