Tamu Massif, Earth’s Extreme Mega Volcano
New volcano, Tamu Massif, among largest in solar system
A recently discovered volcano could be the second largest in our solar system. Tamu Massif is an extinct, shield type volcano 1600km east of Japan. The area of its basalt dome is approximately equal to Great Britain and Ireland added together, or over 100,000 square kilometers. That is comparable to Mars’ Olympus Mons, the largest volcano in our solar system. Tamu Massif formed around 145 million years ago. It’s peak is about two kilometers below sea level, and its peak is 4.4km above the sea floor. By comparison, Olympus Mons would rise over 20km above the sea floor on Earth. William Sager, lead author of the paper which identified Tamu Massif as a single volcano, named the volcano after Texas A&M University, where he worked while researching it.
Tamu Massif, part of the Shatskiy Rise in the northwestern Pacific, was previously thought to be comprised of many smaller volcanos in close proximity to one another. Researchers studied the lava formations of its dome and discovered that the entire dome is composed of the same type of rock, all with the same geologic age. That discovery lead to the conclusion that Tamu Massif is a single volcano. According to Sager, other oceanic plateaus on Earth which were thought to be comprised of multiple volcanoes
“Tamu Massif is the biggest single shield volcano ever discovered on Earth,” Sager said. “There may be larger volcanoes, because there are bigger igneous features out there such as the Ontong Java Plateau, but we don’t know if these features are one volcano or complexes of volcanoes.”
|Tamu Massif stands out among underwater volcanoes not just for its size, but also its shape. It is low and broad, meaning that the erupted lava flows must have traveled long distances compared to most other volcanoes on Earth.The seafloor is dotted with thousands of underwater volcanoes, or seamounts, most of which are small and steep compared to the low, broad expanse of Tamu Massif.The volcano’s top lies about 6,500 feet below the ocean surface, while much of its base is believed to be in waters that are almost four miles deep.|
“It’s not high, but very wide, so the flank slopes are very gradual,” Sager said.
“In fact, if you were standing on its flank, you would have trouble telling which way is downhill. We know that it is a single immense volcano constructed from massive lava flows that emanated from the center of the volcano to form a broad, shield-like shape.
“Before now, we didn’t know this because oceanic plateaus are huge features hidden beneath the sea. They have found a good place to hide.”
“It’s shape is different from any other sub-marine volcano found on Earth, and it’s very possible it can give us some clues about how massive volcanoes can form,” Sager said. “An immense amount of magma came from the center, and this magma had to have come from the Earth’s mantle. So this is important information for geologists trying to understand how the Earth’s interior works.”
See Article in Nature Geoscience (2013) Subscription Required, Abstract available for review.
See Video at http://youtu.be/kj5Z8QSLOZw NMANewsDirect·