Rupture of Denali fault responsible for 7.9-mag Alaskan earthquake

Geologists just back from a reconnaissance of the 7.9-magnitude Alaska earthquake of November 3 confirm that rupture of the Denali fault was the principal cause of the quake. According to Caltech geology professor Kerry Sieh, Central Washington University geological sciences professor Charles Rubin, and Peter Haeussler of the U.S. Geological Survey, investigations over a week-long period revealed three large ruptures with a total length of about 320 kilometers. The principal rupture was a 210-kilometer-long section of the Denali fault, with horizontal shifts of up to nearly 9 meters (26 feet). This places the rupture in the same class as those that produced the San Andreas fault’s two historical great earthquakes in 1906 and 1857. These three ruptures are the largest such events in the Western Hemisphere in at least the past 150 years.

Health of Native Americans on decline before Columbus’ arrival

The health of indigenous people in the Western Hemisphere was on a downward trajectory long before Columbus set foot in the Americas, Ohio researchers say. The rise of agriculture is partly to blame as the demands of tending domestic crops encouraged people to settle in larger communities, where disease was more easily spread. The current research suggests that the overall health of the average person declined with the development of agriculture, government and urbanization.