What happened during the Mount Ontake eruption in Japan?

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Discussion Overview

The discussion revolves around the sudden eruption of Mount Ontake in Japan, focusing on the events that transpired during the eruption, the impact on hikers, and the challenges in predicting such volcanic activity. Participants explore various aspects including eyewitness accounts, geological explanations, and the aftermath of the eruption.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Mount Ontake erupted unexpectedly while many hikers were present, leading to casualties from volcanic rocks and ash.
  • Some participants express concern about the lack of immediate warnings and the current lockdown status of the area.
  • One participant introduces a method for predicting earthquakes and volcanic eruptions, claiming successful past predictions and urging collaboration for a global seismic safety system.
  • Reports indicate that the Japan Meteorological Agency had warned surrounding communities about increased seismic activity prior to the eruption.
  • Experts suggest that the eruption was likely a phreatic eruption, which is difficult to predict due to its nature of involving steam explosions from groundwater and heat.
  • Authorities report that most victims were killed by volcanic rocks, with evidence suggesting they were struck by debris traveling at high speeds.
  • Participants reflect on the helplessness of hikers caught in the eruption, with references to videos capturing the chaos.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the predictability of the eruption and the effectiveness of existing warning systems. The discussion remains unresolved with differing opinions on the methods of prediction and the response to the eruption.

Contextual Notes

There are limitations regarding the assumptions made about the predictability of volcanic eruptions and the definitions of the types of eruptions discussed. The discussion does not resolve the complexities of volcanic activity and its forecasting.

Who May Find This Useful

This discussion may be of interest to those studying geology, volcanology, emergency management, and disaster preparedness, as well as individuals interested in the social impacts of natural disasters.

Astronuc
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Mount Ontake in Nagano Prefecture, Japan, erupted abruptly while over two hundred people were on the summit.

A hiker captures video of group overtaken by ash during Mt. Ontake volcano eruption. They were apparently pelted by rocks/pebbles.

http://www.washingtonpost.com/blogs...p-overtaken-by-ash-during-mt-ontake-eruption/

http://news.yahoo.com/volcano-erupts-japan-injuries-reported-053344700.html

http://www.bbc.com/news/world-asia-29399306http://www.volcano.si.edu/volcano.cfm?vn=283040
No current activity report, but perhaps on Monday they will have some information.
 
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Yikes that is scary! I assume the place is on lock down now?
 
I'm sorry that this message is pretentious.
And I ask you to forgive my mistakes in English.Dear colleagues.

Today has been human victims by the eruption of of a volcano.
I tell you that there is a method of short-term earthquake prediction.
This method can predict and the eruption of the volcano.
I showed more than ten predictions to the expert.
I enclose the letter of expert who recommends to continue working in this direction.

I invite all who are engaged in methods of predicting earthquakes то unite their knowledge to create a global system of seismic safety.
I appeal to the leaders with a request: "Remember that you must defend the people's lives."

I tell that my technique has been successfully tested on real predictions of earthquakes.
I suggest to use complex of methods, together with my technique in order that protect people's lives in seismic catastrophes.

Regards
Alexandr Yagodin

https://sites.google.com/site/earthquakepredict/expertreport2012

https://sites.google.com/site/earthquakepredict/metod-kay-wave-e

https://sites.google.com/site/earthquakepredict/dd1Уважаемые коллеги.

Сегодня погибли люди из-за извержения вулкана.
Я сообщаю вам, что существует метод кратковременного предсказания землетрясений.
Этот метод может предсказывать и время извержения вулкана.
Я продемонстрировал это эксперту более, чем на десяти предсказаниях.
Я прикладываю письмо эксперта, который рекомендует продолжить работу в этом направлении.

Я предлагаю всем, кто занимается методами предсказания землетрясений объединить свои знания в создании глобальной системы сейсмической безопасности.
Я обращаюсь к ведущим руководителям с просьбой: "Помните, что вы должны защитить жизнь людей".

Я сообщаю, что моя методика успешно прошла испытания на реальных предсказаниях землетрясений.
Я предлагаю применить комплекс методов совместно с моей методикой для того, что защитить жизнь людей в сейсмических катастрофах.
 
Japan's Mt. Ontake Is Still Erupting As Questions Emerge About Warnings
http://www.npr.org/blogs/thetwo-way...ntake-is-still-erupting-warnings-are-reviewed
Apparently there were indications of increased seismic activity at the mountain.

"Officials at the Japan Meteorological Agency say they sent messages to communities surrounding Mt. Ontake on the 11th of this month, warning them about a recent increase in volcanic earthquakes."
 
Why Deadly Japan Volcano Erupted Without Warning
https://news.yahoo.com/why-deadly-japan-volcano-erupted-without-warning-205218353.html
Japan has a similar high-tech network for watching its volcanoes. But Saturday's killer outburst was likely a phreatic eruption, a shallow steam explosion that is nearly impossible to predict, experts told Live Science.
. . . .
A phreatic eruption is just water and heat. Think of the inside of a volcano as a solid rock "oven" heated by magma. Earthquakes and shifting magma often jiggle and crack the rock. When a new crack opens in the oven, a blast of heat escapes, similar to opening a kitchen oven's door. If groundwater leaks into the crack, the water immediately flashes into steam from the intense heat. This violent transformation pulverizes the surrounding volcanic rock.
. . .

Phreatic eruptions
https://wwwf.imperial.ac.uk/Earth's...cklibrary/viewglossrecord.php?gID=00000000380
http://volcanoes.usgs.gov/images/pglossary/HydroVolcEruption.php
http://en.wikipedia.org/wiki/Phreatic_eruption
 
Japan police: Volcanic rocks killed most victims
https://news.yahoo.com/japan-police-volcanic-rocks-killed-most-victims-121744423.html

Rescuers have retrieved 47 bodies from the ash-covered summit area of Mount Ontake since Saturday's eruption. Authorities announced Friday that another 16 people are still missing. Search efforts were suspended because of rain.

Doctors concluded that all but one of the bodies showed signs of having been hit by volcanic boulders and rocks, . . . .
. . . .
Experts say hikers near the summit might have been hit by rocks flying as fast as 300 kilometers (190 miles) per hour. Most of the ash fell in the first hour of the explosion, according to the University of Tokyo's Earthquake Research Institute.
. . . .
There would seem to be some need to detect magma chambers close to the surface, where the hot magma can contact ground water.

AFP obtained a CCTV video of the eruption. It seems to run fast, but it happened so quickly in a matter of seconds.
https://uk.news.yahoo.com/video/cctv-footage-shows-japan-volcano-133819109.html

Images taken from cameras of victims on Ontake
http://news.yahoo.com/japan-volcano-victims-leave-photos-last-moments-053541862.html
 
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I remember seeing some video of hikers. How helpless the feeling would be.
 

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