The operator of Japan’s “most dangerous” nuclear plant has said it will comply with a government request to temporarily close the facility and carry out work to improve its ability to withstand earthquakes and tsunamis.
Japan has raised the severity level of its nuclear crisis to the maximum seven, putting the emergency at the Fukushima Daiichi power plant on a par with Chernobyl.
Officials from the nuclear and industrial safety agency (Nisa) confirmed that the crisis level had been raised from five to seven on the international nuclear and radiological event scale.
An earthquake prediction is a prediction that an earthquake of a specific magnitude will occur in a particular place at a particular time (or ranges thereof). Despite considerable research efforts by seismologists, scientifically reproducible predictions cannot yet be made to a specific day or month.
However, for well-understood faults seismic hazard assessment maps can estimate the probability that an earthquake of a given size will affect a given location over a certain number of years. The overall ability to predict earthquakes either on an individual basis or on a statistical basis remains remote.
Once an earthquake has already begun, early warning devices can provide a few seconds’ warning before major shaking arrives at a given location. This technology takes advantage of the different speeds of propagation of the various types of vibrations produced. Aftershocks are also likely after a major quake, and are commonly planned for in earthquake disaster response protocols.
A strange and catastrophic double earthquake was responsible for the tsunami that devastated parts of the South Pacific in 2009, scientists claim. In a rare set of events, an initial 8.1 magnitude earthquake was immediately followed by a second 8.0 shock. The resulting tsunami devastated the South Pacific islands of Tonga and Samoa.
An estimated 192 people died as four waves each more than five metres high surged inland. And international team led by Professor Thorne Lay of the University of California, US, studied the causes of the tsunami. The results are published in the journal Nature. The earthquake was unusual, not only because of the double shock, but also because of the location of the first event. Almost all catastrophic earthquakes – shocks of magnitude 8.0 or bigger – occur at locations where fragments of the Earth’s rigid crust, known as tectonic plates, grind against one another.
ANCHORAGE, Alaska – A powerful earthquake has shaken an Aleutian Island region of Alaska but there is no threat of a tsunami.
The U.S. Geological Survey says the 6.7-magnitude quake struck at 9:56 p.m. Saturday and was centered in the Bering Sea about 110 miles northeast of Dutch Harbor or 930 miles west of Anchorage. The quake hit about 21 miles beneath the seabed.
Alaska Tsunami Warning Center says there was no danger of a tsunami from the temblor.
USGS geophysicist Jessica Sigala says residents of the Dutch Harbor, the nearest sizable community, reported feeling a “weak shaking” from the quake.
A magnitude 6 quake is capable of causing severe damage.
A 3.6 magnitude earthquake rattled the Washington area early Friday, with thousands of residents reporting that they felt the ground shake as they slept or were waking. The U.S. Geological Survey said the quake was centered in Montgomery County and struck at 5:04 a.m.
“The whole house shook,” said Carroll Ripley, of Germantown. “I thought maybe there was an explosion or a plane flew over the house or something.” “I went straight outside to do a perimeter check — in my underwear,” he said. The epicenter was in the Germantown-Gaithersburg area near I-270 and Route 119 (39.167°N, 77.252°W), according to USGS. It was 3.1 miles deep. Authorities across the region said there were no reports of damage. Buses and trains ran on schedule during the morning commute, and traffic moved at its usual pace. Crews in Washington were inspecting underground facilities, vaults, tunnels, bridges and overpasses, according to D.C. Fire and Emergency Medical Services. A natural gas leak at a maintenance depot in the Gaithersburg-Rockville area may be linked to the quake, but officials were unsure of the cause. ”There’s not a single tree branch down,” Montgomery County Fire and Rescue Assistant Chief Scott Graham said. “This was a non-event, thank God.”
An earthquake (also known as a quake, tremor, temblor or seismic activity) is the result of a sudden release of energy in the Earth’s crust that creates seismic waves. Earthquakes are measured with a seismometer; a device which also records is known as a seismograph. The moment magnitude (or the related and mostly obsolete Richter magnitude) of an earthquake is conventionally reported, with magnitude 3 or lower earthquakes being mostly imperceptible and magnitude 7 causing serious damage over large areas.
Intensity of shaking is measured on the modified Mercalli scale. At the Earth’s surface, earthquakes manifest themselves by shaking and sometimes displacing the ground. When a large earthquake epicenter is located offshore, the seabed sometimes suffers sufficient displacement to cause a tsunami. The shaking in earthquakes can also trigger landslides and occasionally volcanic activity.
In its most generic sense, the word earthquake is used to describe any seismic event — whether a natural phenomenon or an event caused by humans — that generates seismic waves. Earthquakes are caused mostly by rupture of geological faults, but also by volcanic activity, landslides, mine blasts, and nuclear experiments. An earthquake’s point of initial rupture is called its focus or hypocenter. The term epicenter refers to the point at ground level directly above the hypocenter.