North American Plate on EARTH Magazine

The Paleo-Bell River: North America's vanished Amazon

Mon, 02 Jul 2018 16:54:20 -0400

The North Saskatchewan River (foreground), at its confluence with the Alexandra River near the rivers' headwaters in the Canadian Rockies, is part of the Saskatchewan River system, which together with the Nelson River watershed is the last remnant of the once-mighty Paleo-Bell River system. Credit: Yvesgagnon1974/istockphoto.com.

By middle school, most students have learned that the Amazon River is the mightiest of Earth’s rivers. Its mean discharge to the ocean of about 209,000 cubic meters per second is more than the combined discharges of the next six largest rivers in the world. Its farthest tributaries rise in the Andes a few hundred kilometers from the Pacific Ocean, and it drains an area of about 7 million square kilometers as it crosses South America to the Atlantic. The Amazon dwarfs North America’s largest river system, the Mississippi, which drains less than half the area of the Amazon and discharges about one-tenth as much water.

Peeling North American Plate causing East Coast earthquakes

Tue, 16 Aug 2016 16:27:23 -0400

In 2011, a magnitude-5.8 earthquake in Virginia damaged buildings in Washington, D.C., including the National Cathedral. Credit: William Leith, U.S. Geological Survey.

On Aug. 23, 2011, a magnitude-5.8 earthquake struck near Mineral, Va., shaking the Piedmont region and damaging several historic buildings in Washington, D.C. The quake caught many people by surprise because the eastern U.S. lies in the interior of the North American Plate, more than 1,500 kilometers from the nearest plate boundary. In a new study, researchers peering beneath the southeastern portion of the North American Plate may have found an explanation for why parts of the region experience more quakes than expected.

Large earthquake rattles Baja California

Thu, 05 Jan 2012 06:41:58 -0500

The Pacific Plate to the west is sliding past the North American Plate to the east, producing numerous strike-slip faults in the region of Mexico's Baja California, shown here. In red: ridge-transform boundaries; in purple: subduction zones; in green: transform faults. USGS National Earthquake Information Center

A magnitude-7.2 earthquake struck northern Baja California, Mexico, at about 3:40 p.m. local time Sunday, according to the U.S. Geological Survey. At least two people were killed, several hundred were injured and thousands were without power as a result of the quake. Aftershocks as high as magnitude 5.0 have continued to rattle the region today.