Familiarize yourself with the designated evacuation area in your neighborhood. Falling objects, toppling furniture and panic present the greatest dangers during an earthquake. Try to protect yourself under a table or doorway.
Do not run outside, and try to remain as calm as possible. If you are in the streets, try to find protection from glass and other objects that may fall from surrounding buildings. After a strong earthquake, turn off ovens, stoves and the main gas valve. Then listen to the radio or television for news. In coastal areas beware of possible tsunami while in mountainous areas beware of possible land slides. Ask in our forum. Home Back. Plan a Trip.
However, before getting into terms like "magnitude" and "seismic scale," let's explore the relationship between Japan and earthquakes--so that you can at least understand a bit about what's happening under your feet first. There are actually well-documented geological reasons why Japan is so earthquake-prone. An earthquake occurs due to the stresses caused by the movements of tectonic plates that comprise the earth.
Japan and earthquakes go hand in hand due to the country's position along the "Pacific Ring of Fire," where it lies across three tectonic plates, including the Pacific Plate under the Pacific Ocean and the Philippine Sea Plate.
As earthquakes can also occur within a tectonic plate, thus occurring on land rather than in the sea and radiating outwards, it is it is foreseeable that a major quake may strike directly under Tokyo or another large urban city that is not accustomed to earthquakes or seismically retrofitted.
Fortunately, though, many buildings are outfitted to better withstand earthquakes. Some are actually designed with the top part able to move with a given earthquake as it happens, while others are meant to actually absorb it and stay steadfastly grounded. Such innovative technology shows that the relationship between Japan and earthquakes--although certainly frightening at times--has produced some useful technology that can help save lives.
The intensity of an earthquake is measured using the term "magnitude", while the impact of the earthquake that can be felt is measured on the "seismic intensity scale. Of course, as you will see below, seismic activity in Japan has been known to go above even the highest level on the scale. Actual effects vary depending on various factors including distance from the epicenter and the geological condition of the area.
With a magnitude of 9, the Great Tohoku Earthquake that originated off the coast of Japan was the most powerful earthquake ever to have struck the country and the fourth strongest earthquake in the world since record-keeping began in As Japan earthquake information available through smartphone apps, the internet and other media will tell you, however, many much smaller tremors and quakes occur daily and even hourly without any destructive effects.
In fact, constant seismic activity in Japan is simply part of life for many locals and expatriates alike. The connection between Japan and earthquakes is an old one, no more so to the people who live there.
Learning from past disasters, Japan is now one of the most earthquake-ready societies in the world, and training starts from young as school children are regularly put through earthquake drills, where the alarm is sound and the students hide under their desks. When an earthquake occurs, JMA immediately issues information on its hypocenter, magnitude and observed seismic intensity. If the seismic intensity is 3 or greater, the Agency issues a Seismic Intensity Information report within one and a half minutes.
The information is provided to disaster prevention authorities via dedicated lines, and reaches the public through local governments and the media. This information also plays a vital role as a trigger for the initiation of rescue and relief operations related to earthquake disasters. Sites of seismic intensity meters as of January 5, Seismic Intensity Seismic intensity describes the scale of the ground motion at a particular location.
It varies with the distance from the epicenter and the surface geology at each point. JMA's seismic intensity scale has 10 degrees 0 imperceptible , 1, 2, 3, 4, 5 lower, 5 upper, 6 lower, 6 upper, 7. The seisimic intensity is measured with a seisimic intensity meter. These estimations are based on prompt analysis of the quake's focus and magnitude using waveform data obtained from seismographs near the epicenter.
The Earthquake Early Warning system is aimed at mitigating earthquake-related damage by allowing countermeasures such as promptly slowing down trains, controlling elevators to avoid danger and enabling people to quickly protect themselves in various environments such as factories, offices, houses and near cliffs.
When an earthquake occurs, JMA estimates the possibility of tsunami generation from seismic observation data. In general, there are three key ingredients that can produce a dangerous earthquake-tsunami combination, he added. First, the earthquake must be at least a magnitude-7 temblor. Second, the quake's epicenter has to be underneath the ocean, Caruso said. And finally, the earthquake has to be shallow.
Today's earthquake was shallow — about 6 miles 10 km underground — but the epicenter was on land, meaning there aren't likely to be any dangerous tsunamis as a result, Caruso said. Given said he hasn't seen many damage reports yet, but Japanese authorities and scientists at the USGS will be monitoring the area for potentially dangerous aftershocks, which are smaller quakes that follow the largest event in a series and that generally decrease in strength.
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