M4.7 quake jolts Kanto region; no tsunami alert issued

:( nooo good at all, My prayers are out

Is that it? It felt much bigger than a 4.7

I was having an English lesson with my student (using the telephone) who lives in Hachioji & suddenly she shouts "Earthquake". I am in Okinawa so obviously i felt nothing. Be careful. The same thing happened Sunday evening while speaking with another student who lives in Kanagawa.

Chiba was a 4. But no mention here....

Mirai, I was also surprised that it was only a 4.7 and so deep as well. It felt bigger or closer in my house.

RedMango - at least did she shout in English? :)

:( nooo good at all, My prayers are out

Prayers for what? The slight dust it unsettled?

If its not a 6+ it never really even throws things from my shelving. Good use as an alarm clock though.

Those who think it was bigger than 4.7 mag quake, how exactly is a 4.7 mag quake supposed to feel then? Don't forget, that the quake was only 50km below which is why the intensity was stronger than a 4.7 quake 100km below ground. Intensity scale is a better measure, where I was it felt like a 2.5 - 3 Shindo.

Japan uses mainly two types of scales for earthquakes The world widely used Richter scales, in this case the 4.7 mag... witch indicates the force of the event, and the very locally use (only in Japan) the Shindo scale, witch is basically how people feel the tremor.

So there is the probability that you can have a Magnitude 3 quake but Shindo 4 (being shindo 5 a very strong movement).

The shindo scale is more subjective and depends much on the terrain, the soil and even the building conditions.

Low calorie "Shake" for breakfast, weight watchers can't complIn.

Thank you Daniel for reminding us again of the difference between the two scales in Japan.

The shindo scale is more subjective and depends much on the terrain, the soil and even the building conditions.

No, that's not at all how the shindo scale works. It measures the shaking at "a point on the earth's distance". That's why you can have different shindo scales from the same earthquake. There is no way that a scientific measuring scale would be so unscientific to measure the subjective measurements.

The effect on people and buildings are approximations.

http://en.wikipedia.org/wiki/Japan_Meteorological_Agency_seismic_intensity_scale

Yep, it was a long 'growly' kind of quake this morn, but no problem! Restart the reactors! (sarcasm)

To find out about each earthquake, go to the WEATHER page on J Yahoo and click on earthquakes.

There you will find a chart of each one as it comes up, with the time of the earthquake on the left, then the time it was logged, the place, and the figures in the two columns on the right give the Magnitude and then the Shindo.

Thus this morning's 7:53 am quake shows logged at 7:58, Ibaraki Prefecture south, 4.7 for the magnitude, and 4 for the maximum Shindo, and then below that it lists all the areas nearby and what shindo they felt.

http://typhoon.yahoo.co.jp/weather/jp/earthquake/

＠Thomas Anderson

Umm.. I know our view point differ greatly in many things (almost everything)... but I think you ought to read carefully the same link you are posting.

Shindo scale is a type of measurement and therefor it has a very well stated definition. For the sake of time and to explain it as simple as possible I used the term "subjective" which is not wrong neither an exaggeration.

It is subjective since the result of the measurement of Shindo scale for the same event in the same time varies from point to point that is measured.

The shindo WAS based on subjective measurements, but since that was unscientific and not objective, it was completely revised since 1996 and the subjective measurements were completely abolished. That's probably what you mean.

Anyway, there's no way that a scientific measuring scale would use subjective measurements.

When I shouted "Earthquake!" this morning, my son quietly stood from his chair (he was having breakfast), then hid himself under the table until I said it was OK. I hope the predicted "Big one" will never come, but it's good to know your children are prepared.

Here's the Japanese meteorological website that gives all the info in English.

http://www.jma.go.jp/en/quake/20140418075441353-180753.html

Japanese legend is that Japan rides on the back of a giant catfish. The Ritcher magnitude scale is no longer widely used. It's been replaced by the moment magnitude scale.

@ebisenAPR. 18, 2014 - 09:21AM JST RedMango - at least did she shout in English? :) good point - thanks !

anyone here living near chiba?? or currently in japan, i hope someone can give any information about the news or what going in there right now. I'm trying to contact my mom using skype, but i can't get through.. pls..

@Shane Raga Eduveje

Don't worry about it; nothing is going on-a quake that small is somewhat unsettling, but there was virtually no damage or injuries. I happily commuted into Tokyo from Chiba this morning about 15 minutes after the quake-slight train delay as they stop running as a precaution during quakes....

"Japanese legend is that Japan rides on the back of a giant catfish."

Actually, that explains a lot.

The magnitude in the epicenter is given in Richter scale but it doesn't give you perception of how strong or weak is the quake on the surface (depending on depth, etc.)

The JMA scale have definition but how you feel is subjective from person to person.

I for myself seems have generated with the time the feeling for shindo scale. This morning was quite weak - I thought 1-2 and looking at the detailed map here it matched my observation: http://www.jma.go.jp/en/quake/20140418075809395-180753.html

The strongest I have felt is 3.5 I think and believe me - it feels strong. Relatively weak at epicenter but still felt strongly at shindo 4 at many places.

People thumbed Shane down for being concerned? What a heartless bunch. I have dear ones in Chiba prefecture too, so I can fully understand his concern.

I was on thee train from Hachioji to Chigasaki and didn't feel a thing.

I once read or heard that as each 'shindo' goes up in number, the way we feel it is ten times stronger than the number below it. Is this the case?

Woke up from this in eastern Tokyo. My first earthquake experience. It wasn't very dramatic, but it felt very weird!

A magnitude 7 hit us here in the Philippines last year and I it felt like the walls were gonna give way any second. Hope the people in Kanto Region are ok.

The next big one is coming for Tokyo. The Olympics Committee is going to regret their decision with the venue selection for the 2020 Games.

This reminds me of the great Hanshin quake where hospital patients survived collapsing concrete ceilings because they were in beds with metal bedsteads which acted as back-up jacks. Bed frames can act like a roll-cage in a sports car.

Since then I have always slept in a bed here, with my water bottle, battery-free wind-up torch/flashlight and whistle beside me, snug as a bug in a rug...