© Mark Legg
A new study shows that an undersea area off the coast of California, known as the California Borderland, is building up seismic stress and could rupture catastrophically, unleashing tsunamis. Here, a map of the California Borderland, showing tectonic features and locations of earthquakes greater than Magnitude 5.5. The dashed box shows the area of the new study. The arrows show relative plate motion between the Pacific and North American plates.
A new study shows that an undersea area off the coast of California, known as the California Borderland, is building up seismic stress and could rupture catastrophically, unleashing tsunamis. Here, a map of the California Borderland, showing tectonic features and locations of earthquakes greater than Magnitude 5.5. The dashed box shows the area of the new study. The arrows show relative plate motion between the Pacific and North American plates.
As the North American and Pacific tectonic plates grind past each other, large chunks of Earth's crust wedged between them get squeezed and twisted off Southern California and Baja California in Mexico. This logjam of crust could cause catastrophic ruptures at two faults along this boundary, setting off undersea temblors of magnitude 7.9 or 8.0, according to new research published April 25 in the Journal of Geophysical Research: Earth Surface.
"We're dealing with continental collision," Mark Legg, a geologist at Legg Geophysical, a geoexploration and hazard assessment company in Huntington Beach, California, said in a statement. "That's fundamental. That's why we have this mess of a complicated logjam."
Comment: It shouldn't be a surprise that the ice caps aren't receding. The fact that global temperatures haven't shown any warming trend over the past 18+ years should provide a clue.