Doug-at-Large

30 Apr 2012

Over 2,000 quakes greater than magnitude 4 since 3/11/11

Apr 30, 2012 12:36pm

29 Apr 2012

Earthquake alert on my iPhone

Apr 29, 2012 7:35pm

But the alarm came simultaneous with the quake, so yes, thank you for letting me know my house is strongly shaking.

25 Apr 2012

It sure woke me up

Apr 25, 2012 7:55am

Tokyo Earthquake 2012: 5.5-Magnitude Quake Reportedly Rattles Japan Capital
http://www.huffingtonpost.com/2012/04/24/tokyo-earthquake-2012_n_1450152.html?ncid=edlinkusaolp00000003

1 Apr 2012

It was a magnitude 5.9 quake

Apr 1, 2012 11:17pm

It was a Richter magnitude 5.9 quake just now, 5- on the Japanese scale of 7 at the epicenter just off Fukushima. Here's the map. The tsunami warning has been called off.

doug

1 Apr 2012

Speaking of earthquakes….

Apr 1, 2012 11:06pm

House shaking a lot right now..

27 Mar 2012

Threatening, active faults found off Boso

Mar 27, 2012 9:51am

Dual jolt could trigger Tokyo temblor up to magnitude 9

Kyodo

Two previously unknown active faults were found off the Boso Peninsula in Chiba Prefecture, with one researcher warning that a jolt in the two faults at the same time could trigger an earthquake of magnitude 8 to 9.

The two faults, one at least 160 km long and the other more than 300 km, were found on the floor of the Pacific Ocean around 100 to 200 km southeast of the southern tip of the peninsula, according to a group of researchers from Hiroshima University, Nagoya University, the Japan Agency for Marine-Earth Science and Technology and other parties.

"The faults have been unmarked and uninvestigated. There is a possibility of strong jolts and tsunami reaching the southern Kanto region (including Tokyo) and the Tokai region (central Honshu). It should be promptly investigated in detail," said research group member Mitsuhisa Watanabe, a professor at Toyo University.

The group will report its findings at a Thursday meeting of the Association of Japanese Geographers in Tokyo.

The group used a bathymetric chart made by the Japan Coast Guard to analyze the geography of the seafloor in detail. It then estimated the location of the active faults by taking into consideration cliffs formed by earthquakes and other elevated features.

According to Watanabe, the two faults were found near a "triple junction," a point where the boundaries of two oceanic plates and a continental plate meet.

Both north-south faults run parallel. The longer fault to the east has a cliff with a height of more than 2,000 meters, while the other one has a cliff more than 3,000 meters high formed by earthquakes, indicating the high possibility that both have repeatedly caused big quakes, he said.

North of the two faults is a focal region for the 1677 temblor, which had an estimated magnitude of 8.0, and the magnitude 7.4 quake that hit in 1953. But the faults seem unrelated to the two quakes, which were likely caused by movement of another active fault, Watanabe said, adding the past movements of the two faults remain unknown.

Active faults have previously been seen as having little connection to earthquakes that occur near ocean trenches. But the same group confirmed last year the existence of a 500-km active fault on the ocean floor along the Japan Trench, which is believed to have moved when the massive earthquake and tsunami disaster hit the Tohoku region last March.

ref: http://www.japantimes.co.jp/print/nn20120327a1.html

16 Mar 2012

Earthquake woke me up )

Mar 16, 2012 4:39am

It was magnitude 5.2, but centered very close to here in southern Saitama. Inland this time. doug

On Mar 16, 2012, at 4:28 AM, Doug Lerner wrote:

> Not even sure what magnitude it was. Going back to sleep. > > doug@4:25 am

16 Mar 2012

Earthquake woke me up )

Mar 16, 2012 4:28am

Not even sure what magnitude it was. Going back to sleep. doug@4:25 am

14 Mar 2012

Here's the map from the earthquake just before - magnitude 6.1

Mar 14, 2012 9:29pm

It was centered in eastern Chiba prefecture - the neighboring prefecture to Tokyo. I live right near the border to Chiba. There it was a 5+ on the Japanese scale of 7. It was also shallow - about 10 km deep.

I don't think there was any damage though.

But there have been 7 earthquakes so far today with magnitudes:

* 4.4

* 4.8

* 6.9 (this was up north)

* 6.1

* 5.7

* 5.4

* 6.1 (the close-by one just now)

11 Mar 2012

The big earthquake - one year later in my neighborhood

Mar 11, 2012 3:31pm

While there were many ceremonies today marking the one year anniversary of the Great East Japan Earthquake, my neighborhood seemed to be a normal Sunday. I strolled by the neighborhood temple and shrine, but both were closed. Plum blossoms (see photos) were in bloom in front of the temple though, and you can see what a beautiful, blue skies day it is. I then walked on to the supermarket where I was when the earthquake hit. They had memorial signs posted (see photo), but otherwise it was a normal shopping day. I didn't watch any if the events on TV. doug