Updated Oct 14, 2011
Some of the bottles and test tubes were labeled “Nihon Yako,” which could be the name of a luminous paint company, according to the ministry. “Yako” means luminous.
The bottles were removed from the premises Friday afternoon and will be stored by a radioactive isotope disposal agency, the ministry said.
Despite the initial fear in the neighborhood that the high radiation levels were coming from radioactive materials emitted by the Fukushima No. 1 nuclear plant, the bottles and test tubes had been sitting underneath the floor boards of the vacant house in the Tsurumaki district, the ministry said.
A radiation level of 600 microsieverts per hour was measured around the surfaces of the bottles, which had been contained in a wooden box.
At 1 meter from the bottles, the reading was 20 microsieverts per hour, science ministry official Takao Nakaya said.
After the ministry officials locked the bottles and tubes into a lead container, the radiation level declined to between 0.1 and 0.35 microsievert per hour, he said.
The owner of the house, an elderly woman who is reportedly around 90 years old, said she had never seen the bottles before and had no idea why they had been stored under the floor, according to the science ministry.
The woman’s deceased husband was an office worker and had nothing to do with radioactive isotopes, the ministry said. The woman lived in the house from around 1953 to February this year but now lives elsewhere.
She lived alone in the house since after her husband died a decade ago. According to the ministry, the owner’s daughter has been checking the home now and then for the past few months.
Although the ministry estimated that the woman may have been exposed to about 30 millisieverts per year, no ill effects from radiation have been confirmed. The calculation was made based on an estimate that the woman had slept in a bed about 2 meters away from the bottles. Experts say that when a person is exposed to 100 millisieverts of radiation, the risk of dying from cancer increases by 0.5 percent.
Radium-226, which in the past was used as luminous paint, has an extremely long half-life — 1,600 years — and emits gamma, alpha and beta rays, said Masahiro Fukushi, a professor of radiation at Tokyo Metropolitan University.
Although alpha rays and beta rays can be blocked by a paper or metallic plate, gamma rays are very powerful and penetrate most materials.
When radioactive radium is ingested or inhaled, it accumulates in bones, and thus can lead to cancer, Fukushi said.
In Japan, the radiation hazard prevention act stipulates that a person or an organization must register with the government when storing substances that contain 10 becquerels per gram of radioactive materials and when the total amount exceeds 10,000 becquerels.
However, unregistered radioactive materials are found at an average of about once a year, mostly in shuttered hospitals or abandoned offices, according to Nakaya of the science ministry.
Mainichi breaking news advisory: High radiation in Setagaya may not be linked to Fukushima radiation…
Setagaya hotspot unrelated to Fukushima (NHK, October 13, 2011)
High levels of radioactivity observed in Tokyo’s Setagaya Ward have been found to have nothing to do with the nuclear disaster in Fukushima.
Experts commissioned by the ward reported a level of 3.35 microsieverts per hour at a 1-by-10-meter area at a sidewalk near a residential fence on Thursday. A maximum of 2.707 microsieverts per hour had been detected in the location a week before.
Later on Thursday, the experts found what seemed to be the source of the radiation — 3 or 4 old jars in a wooden box left in a storage space under the floor of a vacant house facing the sidewalk.
The jars were reportedly dirty and black, and measured about 8 centimeters long and about 6 centimeters wide.
The radiation level of the bottles reportedly exceeded 30 microsieverts per hour — higher than the maximum that could be measured with the experts’ devices.
After obtaining permission from the house’s owner, the experts measured radiation levels on the premises.
The ward says it will take steps to eliminate the radiation while consulting the science ministry and other authorities.
More related news: High radiation affects school routes
Tokyo’s Setagaya Ward has changed school routes in order to keep children away from the small area where a relatively high level of radiation has been detected.
On Thursday morning, about 10 teachers and local officials stood at an intersection to redirect children on their way to a nearby elementary school.
Some children were accompanied by their parents. A mother of a first-grader said she is worried that her child may have passed along the radiation contaminated site every day for over 6 months since the Fukushima accident.
The ward had already made the 10-by-one-meter area along a sidewalk off limits after announcing the finding on Wednesday.
But the ward decided to change school routes in response to concerns voiced by parents.
Earlier: High radiation in Tokyo residential area (NHK) | Small radiation hotspot found in Tokyo’s Setagaya Ward (JAPANTODAY)
TOKYO — Officials said Wednesday they have found a small area in Tokyo’s Setagaya Ward with higher levels of radiation than evacuation zones around the Fukushima nuclear plant.
Setagaya’s mayor said concerned parents monitoring for radiation asked them to conduct further tests on a roadside spot near a kindergarten in Tsurumaki. Its radioactivity level of 2.7 microsieverts per hour slightly exceeded that of an area about 40 kilometers from the Fukushima Daiichi plant.
Mayor Nobuto Hosakai said the cause is being investigated. He said rainwater containing radioactive particles had been dripping from the roof of a building by the sidewalk.
Officials said Wednesday that an estimated annual exposure at the spot wouldn’t pose a health danger. They said the area has been closed off and city officials will also survey nearly 260 parks.
YOKOHAMA — Tests found 195 becquerels of strontium-90 per kilogram in sediment in Yokohama, the first time the radioactive isotope has been detected outside the 100-kilometer radius of the Fukushima No. 1 nuclear power plant.
The sediment, taken from the rooftop gutter of an apartment building in Kohoku Ward in July, was analyzed by a private-run laboratory. The Yokohama city government is conducting its own analysis.
Science ministry surveys found strontium-90, which has a half-life of about 30 years, in Fukushima Prefecture and in southern Miyagi Prefecture, but never beyond 100 km of the crippled Fukushima plant. Yokohama is 250 km from the plant.
The concentration of strontium-90 in the Yokohama sample is larger than the 77 becquerels per kilogram detected in soil in Fukushima city between April and May.
However, a simple comparison is not appropriate because the conditions in Yokohama at the time were favorable for the accumulation of radioactive substances.
“We decided on a reanalysis because the concentration was so high,” a city government official said. “We will decide on our response measures after obtaining the results.”
Strontium has similar chemical properties as calcium. It is soluble in water and tends to accumulate in human bones.
A resident of the five-story apartment house, built seven years ago, collected the sediment and had it tested at the Isotope Research Institute, an analysis laboratory in Yokohama’s Tsurumi Ward.
The laboratory also found a cesium concentration of 63,434 becquerels per kilogram in the same sediment sample. The Yokohama City Institute of Health, which reanalyzed the sample, detected 105,600 becquerels of cesium per kilogram, although the results were not released because the sample came from privately owned land.
The city government was initially not too concerned about checking for strontium content because it was believed to be too heavy to travel long distances from the Fukushima plant and such analyses were expensive.
In early October, however, the city collected sediment samples from the apartment house rooftop in question, a gutter near the apartment house and elsewhere, and took them to the Isotope Research Institute for analysis.
“I knew that strontium would travel over large distances,” said Hiroaki Koide, assistant professor of nuclear engineering at the Kyoto University Research Reactor Institute. “It is no surprise that fallout strontium from the Fukushima No. 1 plant was detected in Yokohama. The concentration appears somewhat large, but I can understand that because the same sample produced a high cesium concentration. Condensation probably took place.”
High radiation dose readings marked in spots in Tokyo, Chiba (Mainichi, October 13, 2011)
Airborne radiation of up to 3.35 microsieverts per hour was recorded Thursday along a sidewalk in a residential area in Tokyo’s Setagaya Ward in an inspection commissioned by the ward, and a citizens’ group detected up to 5.82 microsieverts close to the ground at a children’s theme park in Funabashi, Chiba Prefecture, local officials said.
While officials are still investigating whether the radiation resulted from the nuclear accident, the levels detected were both higher than the 2.17 microsieverts per hour measured Wednesday at the village office in Iitate, Fukushima Prefecture. The village is 45 kilometers from the plant and designated as an evacuation zone due to the relatively high radiation.
Funabashi is about 210 km from the Fukushima plant, while Setagaya is about 230 km away.
In an apparent attempt to calm public concerns over the recent spate of discoveries of contaminated spots in the Kanto area, Chief Cabinet Secretary Osamu Fujimura said Thursday morning the government will continue to step up nationwide monitoring as well as consider more necessary measures.
After learning of the findings at the H.C. Andersen Park, officials in Funabashi began checking radiation levels in the park and the affected area was made off limits by its operator. The contaminated spot is located where accumulated rain water flows into and is not normally accessed by park visitors.
In Setagaya, radiation of up to 3.35 microsieverts per hour was recorded Thursday at a height of 1 meter along the sidewalk in the Tsurumaki district, ward officials said.
The ward officials took samples of tree leaves over a home’s board fence in the area concerned to investigate what type of radioactive material is involved.
They are also trying to work out how to decontaminate the sidewalk, which is regularly used by pupils at a primary school. The area has been cordoned off as a precautionary measure.
The finding comes following Wednesday’s media reports that a high reading of 2.71 microsieverts per hour was detected there earlier this month and that radioactive strontium exceeding normal quantities has been found in sediment atop an apartment building in Yokohama City’s Kohoku Ward, some 250 km away from the nuclear plant.
The reading of 3.35 microsieverts means that if a person were to stay close to the contaminated spot for an entire year, spending eight hours each day outdoors and the rest inside a wooden house, their cumulative annual radiation dose could reach about 17 millisieverts, compared with the government-set allowable limit of 20 millisieverts a year.
Setagaya officials said the higher radiation level could have resulted from an accumulation of rainwater due to the location’s sunken geological formation. But they could not explain why radiation readings taken at a height further above the ground were higher than close to the surface where mud and dust gather.
Research on Oct. 4 and 6 found radiation levels varied widely even along the same sidewalk, with the lowest reading at only 0.088 microsievert and the highest at 2.707 microsieverts near the fence.
More detailed checks Thursday concentrating on the section along the fence detected as little as 0.15 microsievert. At the point with the highest reading, it was 1.34 microsieverts near the ground but 3.35 microsieverts at 1 meter above surface.
The officials said they have used water and other methods in attempt to decontaminate the spot, which was discovered after a resident alerted authorities, but radiation levels have shown little improvement even after the cleaning.
Michikuni Shimo, a professor in environmental radiation at the Fujita Health University, called on the public to remain calm, noting that the amount of radiation detected is not at a level regarded as dangerous.
Radioactive strontium detected in Yokohama (Asahi 2011/10/13)
YOKOHAMA — Tests found 195 becquerels of strontium-90 per kilogram in sediment in Yokohama, the first time the radioactive isotope has been detected outside the 100-kilometer radius of the Fukushima No. 1 nuclear power plant.
The sediment, taken from the rooftop gutter of an apartment building in Kohoku Ward in July, was analyzed by a private-run laboratory. The Yokohama city government is conducting its own analysis.
Science ministry surveys found strontium-90, which has a half-life of about 30 years, in Fukushima Prefecture and in southern Miyagi Prefecture, but never beyond 100 km of the crippled Fukushima plant. Yokohama is 250 km from the plant.
The concentration of strontium-90 in the Yokohama sample is larger than the 77 becquerels per kilogram detected in soil in Fukushima city between April and May.
However, a simple comparison is not appropriate because the conditions in Yokohama at the time were favorable for the accumulation of radioactive substances.
“We decided on a reanalysis because the concentration was so high,” a city government official said. “We will decide on our response measures after obtaining the results.”
Strontium has similar chemical properties as calcium. It is soluble in water and tends to accumulate in human bones.
A resident of the five-story apartment house, built seven years ago, collected the sediment and had it tested at the Isotope Research Institute, an analysis laboratory in Yokohama’s Tsurumi Ward.
The laboratory also found a cesium concentration of 63,434 becquerels per kilogram in the same sediment sample. The Yokohama City Institute of Health, which reanalyzed the sample, detected 105,600 becquerels of cesium per kilogram, although the results were not released because the sample came from privately owned land.
The city government was initially not too concerned about checking for strontium content because it was believed to be too heavy to travel long distances from the Fukushima plant and such analyses were expensive.
In early October, however, the city collected sediment samples from the apartment house rooftop in question, a gutter near the apartment house and elsewhere, and took them to the Isotope Research Institute for analysis.
“I knew that strontium would travel over large distances,” said Hiroaki Koide, assistant professor of nuclear engineering at the Kyoto University Research Reactor Institute. “It is no surprise that fallout strontium from the Fukushima No. 1 plant was detected in Yokohama. The concentration appears somewhat large, but I can understand that because the same sample produced a high cesium concentration. Condensation probably took place.”
Radioactive strontium found in Yokohama, 250 km from Fukushima plant (Mainichi, October 12, 2011)
YOKOHAMA (Kyodo) — Radioactive strontium exceeding normal quantities has been detected in sediment from atop an apartment building in Yokohama, some 250 kilometers from the damaged Fukushima Daiichi nuclear power plant, city officials said Wednesday.
While the discovery of 195 becquerels of strontium 90 in the rooftop sediment has fueled concerns that leaked radiation may have spread further than the government had expected, the officials said the city office is carefully examining where the material came from.
This is the first time strontium at a concentration of over 100 becquerels per kilogram has been found beyond 100 km from the Fukushima plant. The strontium 90 was detected in Yokohama, south of Tokyo, by a private agency that conducted the test upon the request of a resident.
Strontium 90, with a half-life of 29 years, has been detected at concentrations roughly between 10 to 20 becquerels at various places across Japan prior to the nuclear crisis triggered by the March 11 earthquake and tsunami.
After learning about the findings, the Yokohama city is now investigating soil samples collected from areas near the building, the officials said. Meanwhile, the science ministry said it is still uncertain whether the strontium had come from the Fukushima nuclear accident.
Radioactive strontium found on Yokohama condo rooftop (Japantoday, OCT. 13, 2011)
YOKOHAMA —The Ministry of Education, Culture, Sports, Science and Technology said Wednesday that radioactive strontium 90 has been found in sediment on the roof of a condominium in Yokohama.
According to a TBS report, the level of radioactive strontium was 195 becquerels, which is 95 becquerels per kilogram above the government standard.
This is the first time that radioactive strontium with a level higher than the government benchmark has been found so far from the stricken Fukushima Daiichi nuclear power plant, TBS reported.
Yokohama is about 250 kilometers from the Fukushima nuclear plant.
Strontium 90 is a radioactive isotope of strontium, with a half-life of 28.8 years. Its presence in bones can cause bone cancer, cancer of nearby tissues and leukemia.
The science ministry said it has not yet determined where the strontium in the sediment came from.
Japan Today
Yokohama tests soil for radioactive strontium (NHK, October 12, 2011)Officials in Yokohama City are testing soil for radioactive strontium following a report from a local resident in September that the substance had been detected in sediment on the roof of an apartment building.
In September, radioactive cesium more than 80 times the government-set limit of 500 becquerels per kilogram was found in sediment collected from roadside ditches in Yokohama City, which is near Tokyo.
The city later removed sediment from the area.
But the city decided to retest the sample for radioactive strontium due to the request of a local resident.
The resident said a private testing institution had detected 195 becquerels of strontium per kilogram — more than 6 times the government safety limit — in the rooftop sample.
The science ministry says radioactive strontium can accumulate in bones if inhaled and that it poses a cancer risk.
The ministry added that it has found strontium in the soil in Fukushima Prefecture, site of the crippled Fukushima Daiichi nuclear plant. But the agency says it has conducted few checks for the substance outside the prefecture because the amounts detected in Fukushima Prefecture were very small.
Yokohama is located about 250 kilometers from the Fukushima plant.
Residents near Fukushima mountains face nuclear recontamination every rainfall | Gov’t unveils plan to expand decontamination project areas; local reactions mixed (Mainichi Japan) October 12, 201
The government has unveiled plans to sharply expand a government-funded decontamination project to areas with annual radiation emissions of 1 millisievert or more, prompting mixed reactions from local government officials and residents.
Under the plan, the Environment Ministry is to designate those areas with annual radiation exposure of 1 millisievert or more as “priority contamination inspection areas” by the end of November. In collaboration with the central government, local governments are supposed to decide on areas which need to be decontaminated and ways of decontaminating them. The central government will shoulder all the costs.
According to monitoring conducted by the Ministry of Education, Culture, Sports, Science and Technology, there are locations with annual radiation exposure of more than 1 millisievert in Tokyo, Fukushima, Miyagi, Tochigi, Gunma, Ibaraki, Chiba and Saitama prefectures. Drawing on the findings and results of other tests carried out by local municipalities, the Environment Ministry is expected to designate contaminated municipalities as “priority inspection areas”.
Relatively high levels of radiation have been detected in the northwestern part of Chiba Prefecture. Seiichi Someya, head of a radiation-related taskforce at the Kashiwa Municipal Government, said, “It is impossible for the city to shoulder the decontamination costs on its own, and therefore we are thankful for the government support,” adding, “We want to know the details of the project as soon as possible.”
Nevertheless, some local residents are critical of the central government’s response to the spread of radioactive substances from the Fukushima No. 1 nuclear plant. A 41-year-old mother of two children, who took part in a petition urging local governments to measure radiation levels and start cleanup operations, said, “It’s good that the government has acknowledged the need to decontaminate areas with annual radiation of 1 millisievert or more, but it is rather late. We already knew by late April that this area was badly contaminated. Measures could have been taken earlier.”
In Tokyo, meanwhile, Katsushika Ward has been measuring radiation levels at parks in seven locations every week since the end of May. Some of the parks still register 0.23 microsieverts per hour.
In August, the ward measured sand pits at 398 locations in such places as elementary and middle schools, parks and the like. The ward has moved to replace sand registering more than 0.25 microsieverts per hour with non-contaminated sand at 20 locations.
The “Kanamachi 2-Chome Tokiwa Park” in the ward registered 0.24 microsieverts per hour on Oct. 6. A 42-year-old office worker passing by the park said, “Because I have an elementary school child, we will feel secure if decontamination is done in accordance with the government plan.”
 |
| Hot water: Hiroko Aki of Nagareyama, Chiba Prefecture, uses a becquerel counter Tuesday at the newly opened Bec-Miru facility in Kashiwa to check well water from her home for radiation. YOSHIAKI MIURA |
Facility in Chiba lets public test for radiation (Japan Times, Oct 12, 2011)
KASHIWA, Chiba Pref. — People concerned about radiation in their food, water and the soil at nearby playgrounds thronged to a new facility that opened Tuesday in Kashiwa, Chiba Prefecture — a well-known radiation hot spot — that will allow users to measure radiation levels at an affordable price.
“People can bring in whatever they want here and test the level of radiation themselves,” Motohiro Takamatsu, 47, representative of the Bec-Miru facility, told The Japan Times.
Takamatsu’s facility, about a six-minute walk from JR Kashiwa Station, boasts sofas, a playground and a pastel-colored reception area where six staff members greet customers. In the back of the room are eight state-of-the-art becquerel counters, which Takamatsu imported from German company Berthold Technologies and has made available to locals for a fee.
“Those machines capture gamma rays, meaning they can’t detect the levels of plutonium or strontium. They are for measuring levels of cesium” in any given product, Takamatsu explained.
The LB 2045 gamma spectroscopy system, which costs about ¥2.5 million each, can detect the level of cesium contamination down to a minimum of 10 becquerels from a 1-kg specimen in about 15 to 20 minutes.
Customers will be able to use the machine for 20 minutes for ¥3,980. The LB 200 models, which cost ¥1 million each, are able to detect cesium contamination levels of a minimum of 20 becquerels and will be available for ¥980 per 20 minutes.
“We have set up four LB 2045 machines and four LB 200 models,” Takamatsu said. “We need to have at least 40 to 50 customers a day to make ends meet.”
Takamatsu, who has two preteen daughters and works as a software engineer in the city, was originally planning to purchase a new car with the money he had saved up from his job.
But after the March 11 disaster struck and news broke that parts of northwestern Chiba could be heavily contaminated, the safety of food and soil became the priority for him as well as other parents in the area.
He decided to purchase German spectroscopy systems in June, hoping they would provide a sense of safety for locals concerned with radiation. Thanks to his investment, residents of northwestern Chiba Prefecture, where high levels of cesium were detected in areas around Kashiwa and Nagareyama, can now take the matter into their own hands.
Customers, who will need to make reservations before using the machines, are expected to bring in anything from garden soil, rice, meat, vegetables and even mother’s milk. They will be operating the machines on their own after an on-site briefing by staff.
Takamatsu had no prior knowledge of radiology but read books, contacted college professors and experts in the field and eventually gained expertise.
“We’ve been testing the machines, and some of the local soil actually surpassed the 10,000-becquerel mark,” Takamatsu said.
To avoid any hazard to the store staff and others, every specimen customers bring in will undergo quick tests at the entrance for any serious radioactive contamination.
“If the contamination passes 1 microsievert at that point, which roughly translates to at least 100,000 becquerels, we will not allow our customers to use the machines,” Takamatsu said.
Junko Kasahara, who runs a small organic farm with her husband in nearby Nagareyama, was one of the first in line Tuesday.
“We’ve had eggs, cabbage, onions, pumpkins and other products tested at other research facilities, but it costs ¥15,000 every time, plus the results only become available after a week,” the 37-year-old Kasahara said.
On Tuesday, Kasahara brought in some soil and leafy vegetables from her farm to have them tested at Bec-Miru.
“They showed no contamination and were safe,” she said, noting the quick service and the affordable price will not only come in handy for her but for providing quick information to her customers as well. “The store is very easy to access, and I will probably do the preliminary checks here.”
Japanese sake tested for radiation (NHK, October 12, 2011)
Japan’s tax officials have conducted preliminary radiation checks on sake and other alcoholic beverages in the wake of the accident at the Fukushima Daiichi nuclear power plant.
The National Tax Agency conducted a trial test on Wednesday ahead of extensive assessment. The agency will conduct tests of all breweries and factories located within 150 kilometers of the troubled plant. Brewing facilities outside the radius will also be randomly tested.
Checks will investigate if either water used for brewing or alcoholic products have radioactive materials. At the trial on Wednesday a testing apparatus called a survey meter for measuring radiation was used. The officials poured sake and wine to the equipment and recorded the results.
The officials say they only detected normal levels of background radiation.
The agency says that if high levels of radioactive materials are detected, it will send samples to a government-backed alcoholic research institute in Hiroshima, western Japan for detailed analysis.
If radioactive materials above the government-set limit are detected in the analysis, the agency will notify related prefectures and ask them to take necessary measures, including banning shipments.
The agency plans to carry out the tests at 6 of its regional tax bureaus as early as next week.
The agency will release all test results on its website.
Rice and barley, the main ingredients for the alcoholic beverages, have already been tested for radiation.
The agency hopes the testing will put consumers at ease.
Drill confirms safety of Fukushima nuclear plant (NHK, Oct 13) | Radioactive substance levels in Fukushima reactor building drop below legal limits (Mainichi)
Radiation 47 times higher than criteria detected from nuclear waste
The radiation readings were registered in a safety check of vitrified waste delivered to the Rokkasho facility on Sept. 15.
So far, the radiation level fell below 4 becquerels for one of the three worrisome canisters and workers continue decontaminating the remaining two, Kyushu Electric said.
FUKUOKA (Kyodo) — Radiation dosages 47 times higher than acceptance levels have been detected from vitrified radioactive waste at a storage facility in Rokkasho, Aomori Prefecture, Kyushu Electric Power Co. said Thursday.
Up to 190 becquerels of both beta and gamma rays were detected from the surface of three of 28 canisters of waste from spent nuclear fuel reprocessed in Britain. The storage facility’s acceptance level is set at 4 becquerels, Kyushu Electric said, adding there has been no leakage of radiation.
The spent fuel came from nuclear reactors operated by Kyushu Electric Power Co.
Japan Nuclear Fuel Ltd., which operates the High-Level Radioactive Waste Storage Center in Aomori, northeastern Japan, is looking into why three of the vitrified waste canisters are emitting radiation at such levels.
Kyushu Electric said the vitrified waste was a by-product of the reprocessing in Britain of spent nuclear fuel shipped there by it and two other Japanese power companies. Radioactivity readings were below the criteria before shipments from Britain, it said. …
Shinmoedake volcano in Kyushu may become active again soon: experts(Mainichi Japan) October 12, 2011
Mount Shinmoedake in the central part of the volcanic Kirishima mountain range in southern Kyushu could resume its volcanic activities within several months as magma continues to be piled up deep underground, the Coordinating Committee for Prediction of Volcanic Eruptions said on Oct. 11.
Within about four months, the amount of accumulated magma is likely to increase close to levels registered in late January when the volcano became active, the committee said.
According to the group, GPS monitoring found that the 1,421-meter volcanic mountain has been swelling steadily — an indicator of the increasing size of accumulated magma. If the amount of accumulated magma reaches levels registered in late January, Mount Shinmoedake, which straddles Miyazaki and Kagoshima prefectures, could resume its volcanic activities on a scale comparable to that for late January, the committee said. Mount Shinmoedake has erupted seven times since mid-June after remaining quiet for about two months since mid-April.
Committee chairman Toshitsugu Fujii said, “There could be various scenarios. It is hard to think the volcanic activities will stop quickly.” He said the mountain could erupt on a scale larger than that for late January, and other craters in the Kirishima mountain range could also erupt.
The Meteorological Agency maintained its volcanic alert at level 3, banning people from entering the mountain.
Scientists: 3/11 fault slip matched pre-quake strain accumulation(Asahi, 10/13)
The pattern of extensive strain accumulation on a tectonic plate before March 11 largely matched the actual fault slip that caused the Great East Japan Earthquake, a team of researchers said.
The finding could help forecast the spatial extent of a coming earthquake based on strain accumulation data.
The team, led by Kazuki Koketsu, professor at the Earthquake Research Institute of the University of Tokyo, used seismograms and Global Positioning System measurement network data to analyze the extent of the fault slip during the March 11 earthquake.
They also analyzed data from a quiescent period before the earthquake and evaluated the strain accumulation, including distortions, due to the continental plate being dragged down by the oceanic plate, with which it was bonded.
They found that the distributions of the two quantities were largely similar.
Based on records of known earthquakes before the March 11 disaster, it was believed that earthquakes of magnitude 7 to 8 occurred separately along different sections of the Japan Trench.
However, six earthquakes coincided and created the magnitude-9.0 mega-quake on March 11.
According to an analysis by the Geospatial Information Authority of Japan, strain accumulation is also distributed more extensively than any single hypothetical seismic source along the Nankai Trough, an underwater plate interface off the southern coast of Japan.
There are instances in the past when an earthquake simultaneously ruptured the Tokai, Tonankai and Nankai seismic sources along the Nankai Trough.
Following the Great East Japan Earthquake, attention is focused on the possibility of another mega-quake bigger than any single event envisaged so far.
Extensive strain accumulation has also been found along the Kuril Trench to the east of Hokkaido.
DPJ nuclear power skeptics finding themselves isolated (Asahi, 2011/10/13)
IAEA team to help decontaminate area around nuclear plant (Japan Times)
Panel to suggest provisionally hiking annual exposure limit
Evacuee kids’ thyroids need monitoring (Japan Times, Oct 5)
“NAGANO — Hormonal and other irregularities were detected in the thyroid glands of 10 out of 130 children evacuated from Fukushima Prefecture, a Nagano Prefecture-based charity dedicated to aid for the victims of the 1986 Chernobyl nuclear accident said Tuesday.
The Japan Chernobyl Foundation and Shinshu University Hospital did blood and urine tests on youngsters aged up to 16, including babies under age 1, for about a month through the end of August in Chino, Nagano, when the children stayed there temporarily after evacuating from Fukushima.” Read the rest here…
EDUCATION IN JAPAN COMMUNITY Blog 