Earth Changes
The finding, detailed in the March issue of the journal Geology, suggests old and new faults might generate different types of earthquakes.
Researchers were able to see the wear patterns by using a fairly new technology called laser imaging detection and ranging (LIDAR) to create detailed topographical maps of the vertical sides of exposed fault lines. Like radar, LIDAR sends out a pulse of energy and then records information from bounced back reflections. LIDAR is more sensitive than radar, and can collect data points as close as every 0.12 inches during scans of enormous rock faces.
"Ann said losing toes and going forward at all costs was never part of the journey," said Ann Atwood, who helped organize the expedition.
North Americans are more familiar with the Sican than we think. Because Spanish conquistadors melted down most of the gold treasures of the Inca (the Sican's successors), 80 per cent of "Incan" gold artifacts in museums are in fact of Sican workmanship.
The Sican people fished, farmed, traded, mined, built temples and sacrificed other humans in the worship of a bird-faced god 1,100 years ago in the Lambayeque region of northern Peru. They buried their priest-leaders in shaft tombs, some 10 to 20 metres underground, where they remained relatively safe from European predators.
It's the well being of pets.
"This weather is not good for man or beast," said Stacey Robertson, the chief animal control officer for Pottawattamie County.
Apparently, however, pet owners in the county and in Council Bluffs have taken care of their animals during the latest winter blast.
"We haven't had a lot of calls to collect stray animals, which is good," Robertson said. "People have pretty much kept them in."
Tundra is land area where tree growth is inhibited by low temperatures and a short growing season. In the Arctic, the tundra is dominated by permafrost, a layer of permanently frozen subsoil.
The only vegetation that can grow in such conditions are grasses, mosses and lichens. Forests of spruce trees and shrubs neighbor these tundra areas, and the boundary where they meet is called the treeline.
In summer, the permafrost thaws, and the tundra becomes covered in bogs and lakes, allowing a unique habitat for plants. Climate change, meanwhile, has extended the summer warming season and promoted tree growth, causing the treeline to encroach on the tundra.
Both places are sources of gas hydrates, strange icelike substances that trap methane-the primary component of natural gas.
"It's not frozen gas," explained Timothy Collett of the U.S. Geological Survey in Denver. "It's [formed] from the interaction of gas and water."
The hydrates were discovered in 1983, and no one knows how many of them exist.
But there appear to be enough hydrates to represent a larger energy source than all of the word's gas, oil, and coal combined, Collett said at a meeting of the American Physical Society in Denver, Colorado, on March 5.