Thursday, May 10, 2012
What's Happening Underneath Mt. Fuji?
The results of a geological survey were reported in The Japan Times online.
Friday, May 11, 2012
Active fault may lie directly beneath Mount Fuji: researchers
Kyodo
An active fault as long as 30 km may lie directly beneath Mount Fuji, a team of researchers has said in a recent survey report.
The possible fault was detected through a simulated earthquake conducted during a crustal survey over a distance of around 34 km from Fujiyoshida in Yamanashi Prefecture to Susono in Shizuoka Prefecture, said Hiroshi Sato, professor at the Earthquake Research Institute at the University of Tokyo.
"More studies are needed to determine the depth and other details of the fault," Sato added.
While faults have been confirmed around Mount Fuji, little is known about the seismic structure beneath Japan's highest mountain due to mudflows caused by a huge landslide that occurred around 2,600 to 2,900 years ago, as well as thick layers of volcanic ash.
Monday, May 7, 2012
What's Happening Under the Sea?
Tuesday, May 8, 2012
Extremely slow quakes confirmed
Jiji
Extremely slow earthquakes occurred at the Nankai Trough, south of Japan, in March 2009, Japanese researchers have reported.
Crustal ruptures in the earthquakes took 30 to 100 seconds, compared with some 1 to 2 seconds in ordinary quakes with magnitude of around 4, said the researchers, including members of the Japan Agency for Marine-Earth Science and Technology, or JAMSTEC.
The findings were published in the latest online edition of the British journal Nature Geoscience.
The low-frequency earthquakes took place in unexpectedly shallow areas of the plate boundary, suggesting such areas may be a source of so-called tsunami earthquakes that cause disproportionately large tsunami for their seismic energy, the researchers said.
By setting up broadband seismometers off the coast of Tanabe, in Wakayama Prefecture, they observed the earthquakes for 10 days from March 22, 2009.
"Our research could lead to understanding the mechanism of tsunami quakes, which could cause severe damage, and it is necessary to continue the research for the long run," said Hiroko Sugioka, a JAMSTEC researcher.
(from The Japan Times online, May 8, 2012)
Thursday, April 5, 2012
A Great Time to be in Science
Remember: All the discoveries have not been made yet. Here's a comment about the feathered dinosaur remains uncovered in China:
“This is a great time to be a dinosaur paleontologist,” said Dr. Norell, whose research concentrates on fossils from China and the Gobi Desert of Mongolia. “The feathered dinosaurs show how the whole conception of dinosaurs has really changed in the last 15 years.”
“This is a great time to be a dinosaur paleontologist,” said Dr. Norell, whose research concentrates on fossils from China and the Gobi Desert of Mongolia. “The feathered dinosaurs show how the whole conception of dinosaurs has really changed in the last 15 years.”
Chill! Here Comes a New Discovery
One of the reasons researchers like Dr. Masaaki Kimura, professor emeritus of The University of the Ryukyus, encourages young people to join his team is this: all the world's discoveries have not yet been made.
This new one is not from Yonaguni, but from the mainland of Japan, where something important has been hidden in plain sight since forever.
Here is the story of the "discovery" of Japan's first glaciers:
Friday, April 6, 2012
First glaciers in Japan recognized
By MINORU MATSUTANI
Staff writer
Scientists have found three glaciers in Toyama Prefecture, the first recognized in Japan and the southernmost in East Asia.
Researchers from the Tateyama Caldera Sabo Museum discovered the three slow-moving chunks of ice in the Hida Mountain Range, otherwise known as the Northern Alps.
Their research paper submitted to the Japanese Society of Snow and Ice was accepted Tuesday, the museum said.
A glacier is defined as a large mass of ice that over many years "flows" owing to its great weight, according to the Japanese Society of Snow and Ice. They are often found on high mountains, such as the Himalayas, and have even been found on Mount Kilimanjaro, which is almost on the equator. Until now, the southernmost glaciers in East Asia were on Russia's Kamchatka Peninsula.
"We have known something similar to glaciers existed, so we checked to see if the masses of ice are moving," said Hajime Iida, a researcher for the museum.
Between 2009 and 2011, Iida's team used "ice radar" to find two glaciers on Mount Tsurugi and one on Mount Tateyama. Ice radar sends electronic waves into the ice to measure how thick it is.
Using GPS, the team confirmed that the masses of ice are moving between 10 and 30 cm a month.
The masses are 27 to 30 meters deep and 400 to 1,200 meters long. The Japanese Society of Snow and Ice will publish the research paper in its journal Seppyou (Snow and Ice) in May, the museum said in a news release.
"The group used the latest equipment to research the movement of ice chunks very concretely. The value of this research is high," said Keishi Ishimoto, the journal's chief editor.
There is no international organization that officially recognizes glaciers. Therefore, unless researchers abroad express opposition to the group's paper, it would be fair to say that the three masses of ice are indeed glaciers, Iida said.
Information from Kyodo added
This new one is not from Yonaguni, but from the mainland of Japan, where something important has been hidden in plain sight since forever.
Here is the story of the "discovery" of Japan's first glaciers:
Friday, April 6, 2012
First glaciers in Japan recognized
By MINORU MATSUTANI
Staff writer
Scientists have found three glaciers in Toyama Prefecture, the first recognized in Japan and the southernmost in East Asia.
Researchers from the Tateyama Caldera Sabo Museum discovered the three slow-moving chunks of ice in the Hida Mountain Range, otherwise known as the Northern Alps.
Their research paper submitted to the Japanese Society of Snow and Ice was accepted Tuesday, the museum said.
A glacier is defined as a large mass of ice that over many years "flows" owing to its great weight, according to the Japanese Society of Snow and Ice. They are often found on high mountains, such as the Himalayas, and have even been found on Mount Kilimanjaro, which is almost on the equator. Until now, the southernmost glaciers in East Asia were on Russia's Kamchatka Peninsula.
"We have known something similar to glaciers existed, so we checked to see if the masses of ice are moving," said Hajime Iida, a researcher for the museum.
Between 2009 and 2011, Iida's team used "ice radar" to find two glaciers on Mount Tsurugi and one on Mount Tateyama. Ice radar sends electronic waves into the ice to measure how thick it is.
Using GPS, the team confirmed that the masses of ice are moving between 10 and 30 cm a month.
The masses are 27 to 30 meters deep and 400 to 1,200 meters long. The Japanese Society of Snow and Ice will publish the research paper in its journal Seppyou (Snow and Ice) in May, the museum said in a news release.
"The group used the latest equipment to research the movement of ice chunks very concretely. The value of this research is high," said Keishi Ishimoto, the journal's chief editor.
There is no international organization that officially recognizes glaciers. Therefore, unless researchers abroad express opposition to the group's paper, it would be fair to say that the three masses of ice are indeed glaciers, Iida said.
Information from Kyodo added
Tuesday, January 24, 2012
A Tale of Two Ancient Cities
Imagine this scenario. It is almost two millennia ago. You live in a beautiful, seaside city. The surrounding land is flat and fertile. Water is abundant. As a bonus, your city sits beside a deep water harbor and enjoys the benefits of foreign trade. Your lovely city is called Bathonia.
Farther along the coast, there is another location. Water is scarce. There are steep hills overlooking another deep water harbor. Trade is possible, but the lack of water is a serious handicap. Food has to be grown elsewhere. This location came to be called Constantinople.
For some reason not fully understood, about two millennia ago, the population abandoned Bathonia and built up Constantinople. Why?
One scenario posits that Constantinople was easy to defend from the Roman legions and other attackers. This makes perfect sense. The history of the Crusades proves the defensibility of Constantinople.
But what if something else were true? Some of the ruins of Bathonia are now submerged in a lake, cut off from the Sea of Marmara. What if a devastating earthquake suddenly closed the entrance to Bathonia’s deep-sea harbor? This, too, would make perfect sense. A natural disaster devastating a hometown is a good reason to pull up stakes and rebuild elsewhere.
Studies of Bathonian ruins made accessible by a drought that lowered the water level may shed light on why Bathonia was abandoned in favor of Constantinople, now called Istanbul.
But what about Yonaguni? Where did everyone go? Why did they leave? It is so much harder to find answers when your study target is at the bottom of the sea, scoured by fast moving ocean currents.
Farther along the coast, there is another location. Water is scarce. There are steep hills overlooking another deep water harbor. Trade is possible, but the lack of water is a serious handicap. Food has to be grown elsewhere. This location came to be called Constantinople.
For some reason not fully understood, about two millennia ago, the population abandoned Bathonia and built up Constantinople. Why?
One scenario posits that Constantinople was easy to defend from the Roman legions and other attackers. This makes perfect sense. The history of the Crusades proves the defensibility of Constantinople.
But what if something else were true? Some of the ruins of Bathonia are now submerged in a lake, cut off from the Sea of Marmara. What if a devastating earthquake suddenly closed the entrance to Bathonia’s deep-sea harbor? This, too, would make perfect sense. A natural disaster devastating a hometown is a good reason to pull up stakes and rebuild elsewhere.
Studies of Bathonian ruins made accessible by a drought that lowered the water level may shed light on why Bathonia was abandoned in favor of Constantinople, now called Istanbul.
But what about Yonaguni? Where did everyone go? Why did they leave? It is so much harder to find answers when your study target is at the bottom of the sea, scoured by fast moving ocean currents.
Monday, November 7, 2011
Snake-Free!
Zamami Island, about two hours west of Naha (Okinawa) by fast ferry, is in the Kerama island group. Among the island's many charms is the fact that it does not host the deadly habu snakes found on Okinawa proper. Yonaguni is also habu-free.
The most common explanation for the fact that some islands are infested with habu and others are not goes like this. The islands that have snakes living on them were once connected. When the land bridges that connected them subsided below sea level, they became independent islands with shared animal populations. The islands that do not have snakes came into being separately, when sub-sea sedimentary rock layers were fractured, tilted, and pushed up above sea level.
The most common explanation for the fact that some islands are infested with habu and others are not goes like this. The islands that have snakes living on them were once connected. When the land bridges that connected them subsided below sea level, they became independent islands with shared animal populations. The islands that do not have snakes came into being separately, when sub-sea sedimentary rock layers were fractured, tilted, and pushed up above sea level.
An Ancient Earthquake (Zamami Island)
The two dark stripes and their discontinuities tell of earthquakes that happened in ancient days. The larger right/left discrepancy is close to one foot. The one above that is a few inches.
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