Sunday, May 31, 2015

The biggest volcano on earth and yesterday's 7.8M earthquake in Japan

Yesterday, I came across a story about a giant volcano discovered below sea in the northwest Pacific and identified in 2013 as the "biggest volcano on earth and one of the biggest in the solar system". (See story below)

Called TAMU MASSIF the giant shield volcano had been thought to be a composite of smaller structures, but now scientists say they must rethink long-held beliefs about marine geology.

By coincidence, a 7.8M earthquake struck in the same area, also yesterday, (see maps below), where the said massive volcano has been hiding for 145 million years.



New Giant Volcano Below Sea Is Largest in the World

Tamu Massif in the northwest Pacific challenges traditional views of ocean science.
By Brian Clark HowardNational Geographic
A volcano the size of New Mexico or the British Isles has been identified under the Pacific Ocean, about 1,000 miles (1,600 kilometers) east of Japan, making it the biggest volcano on Earth and one of the biggest in the solar system.
Called Tamu Massif, the giant shield volcano had been thought to be a composite of smaller structures, but now scientists say they must rethink long-held beliefs about marine geology.
“This finding goes against what we thought, because we found that it’s one huge volcano,” said William Sager, a geology professor at the University of Houston in Texas. Sager is lead author in a study about the find that was published this week in the peer-reviewed journal Nature Geoscience.
“It is in the same league as Olympus Mons on Mars, which had been considered to be the largest volcano in the solar system,” Sager told National Geographic.
Tamu Massif is a rounded dome that measures about 280 by 400 miles (450 by 650 kilometers), or more than 100,000 square miles. Its top lies about 6,500 feet (about 2,000 meters) below the ocean surface, while the base extends down to about 4 miles (6.4 kilometers) deep. Tamu Massif dwarfs the largest active volcano on Earth, Mauna Loa in Hawaii, which measures about 2,000 square miles (5,200 square kilometers).
Made of basalt, Tamu Massif is the oldest and largest feature of an oceanic plateau called the Shatsky Rise in the northwestern Pacific Ocean. The total area of the rise is similar to Japan or California.
Sager started studying Tamu Massif about 20 years ago. He named it Tamu Massif because Tamu is short for Texas A&M University, where the scientist worked at the time; massif is French for “massive” and is a scientific term for a large mountain.
The 7.8M Earthquake May 30, 2015  189km WNW of Chichi-shima, Japan Depth: 677.6 km


Location of Tamu Massif