Group items tagged

In the days leading up to some recent moderate-sized earthquakes, instruments nearby have picked up brief low-frequency pulses in Earth’s magnetic field

A few scientists have proposed that such pulses, which seemed to become stronger and more frequent just before the earthquakes occurred, could serve as an early warning sign for impending seismic activity

Now, a team has come up with a model for how these magnetic pulses might be generated, though some critics say they may have a humanmade origin.

Alaska earthquake

In 1965, south central Alaska was rocked by North America's greatest earthquake. (At 8.3-8.5 on the Richter scale, it released over twice the energy of the 1906 San Francisco earthquake.) Its epicenter was near Price William Sound, along a 1,000 km thrust fault where the Pacific plate subducts under the North american plate. The earthquake tilted at least 120,000 sq km. Some landmasses were thrust up locally as high as 25 m; elsewhere land sank as much as 2.5m. The shock was felt over almost 1,300,000 sq km. Extensive coastal damage resulted from submarine landslides and tsunamis which caused 122 of the 131 deaths. Property damage cost was about $311 million. Tsunami damage reached Crescent City, Calif. Tens of thousands of aftershocks indicated that the region of faulting extended about 1,000 km.

In March 2011, a devastating tsunami struck Japan's Tohoku region

Now, researchers have uncovered the cause of this tsunami, shedding light on what displaced the seafloor off the northeastern coast of Japan

Learning more about the 2011 tsunami and its causes is an important step for monitoring future events.

According to prevailing theories of plate tectonics, the Indo-Australian plate began to deform internally about 10 million years ago

thrusting the Himalayas up and slowing India down

Most scientists think that the Australian portion forged ahead, creating twisting tensions

Canadian earthquake   In 1700, an earthquake, the most intense Canada has ever seen, hit the sea floor off the British Columbia coast. Long before Europeans first landed on Vancouver Island, native legend tells of a great disaster. The sea rose in a heaving wave, and landslides buried a sleeping village. Myth was resolved with science in 2003 by government research. Earthquakes of that intensity cause tidal waves, and Japanese written history tells of a massive tsunami striking fishing villages the next day along the coast of Honshu, killing hundreds. Coupled with geological evidence of the level 9 quake, the connection was clear. Mythology and seismology came together to validate history.

Seismologists have known for years that the Indo-Australian plate of Earth's crust is slowly breaking apart

quake was caused by at least four undersea fault ruptures

within a 2-minute, 40-second period

Santorini locals began to suspect last year that something was afoot with the volcano under their Greek island group

Wine glasses occasionally vibrated and clinked in cafes, suggesting tiny tremors, and tour guides smelled strange gasses.

satellite radar technology has revealed the source of the symptoms. A rush of molten rock swelled the magma chamber under the volcano by some 13 to 26 million cubic yards (10 to 20 million cubic meters)—about 15 times the volume of London's Olympic Stadium—between January 2011 and April 2012

Marie Byrd Land is a desolate region of Antarctica buried deep beneath the West Antarctic Ice Sheet

Historic eruptions have punctured the ice sheet, creating a chain of volcanoes amid the ice

researchers have shown that molten rock still stirs deep underground

A spectacular meteor wowed stargazers across the United Kingdom Friday (Sept. 21) when it flared up and shattered into piece

spotted by observers across Scotland and northern England as well as Ireland

Many observers captured views of the meteor on camera

Scientists have begun piecing together the characteristics of the meteor that exploded over Russia on the morning of February 15, using data from seismic instruments that track earthquakes and microphones designed to detect sonic booms from nuclear explosions

The explosion had the equivalent of up to 500,000 tons of TNT

about 30 times the energy output of the Hiroshima atomic bomb

Scientists have discovered a new planet orbiting a Sun-like star, and the exoplanet is the smallest yet found in data from the Kepler mission

Kepler-37b, is smaller than Mercury, but slightly larger than Earth’s Moon

discovery came from a collaboration between Kepler scientists and a consortium of international researchers who employ asteroseismology

Mount St. Helens

In 1980, following a weeklong series of earthquakes and smaller explosions of ash and smoke, the long-dormant Mount St. Helens volcano erupted in Washington state, U.S., hurling ash 15,000 feet into the air and setting off mudslides and avalanches. The eruptions caused minimal damage in the sparsely populated area, but about 400 people - mostly loggers and forest rangers - were evacuated. The explosion was characterized as the equivalent of 27,000 atomic bombs. The cloud of ash eventually circled the globe

The team successfully established contact that afternoon — notwithstanding a minor earthquake in the area — at a heart-thumping transmission rate of 512 bits per second.

approval from NASA to attempt contact, and that go-ahead came on May 29th

spacecraft has two transponders,

transponder A and Transponder B

Transponder B is normally the engineering telemetry transponder and transponder A is the ranging transponder