Although we did a Friday Foto post on volcanic eruptions last month, a new study suggests that mega volcanoes may have led to the extermination of half of Earth’s species some 200 million years ago.
According to LiveScience, the release of gases from giant eruptions caused climate change that led to the End-Triassic Extinction, the widespread loss of land and sea species that made way for the rise of the dinosaurs, the research says.
The new study, published Thursday, March 21, in the journal Science, shows that a set of major eruptions spanning from what is now New Jersey to Morocco occurred very close to the time of the extinction.
Scientists suspected previously that such volcanic activity and the resultant climate change were responsible for this major extinction and at least four others. But researchers weren’t able to constrain the dates of the eruptions and extinctions well enough to prove the hypothesis. The new study, however, dates the End-Triassic Extinction to 201.56 million years ago, the same time the volcanoes were blowing their tops.
Facts and figures about volcanoes
A volcano is a mountain that opens downward to a reservoir of molten rock (like a huge pool of melted rocks) below the earth’s surface. Unlike mountains, which are pushed up from the earth’s crust, volcanoes are formed by their buildup of lava, ash flows, and airborne ash and dust. When pressure from gases and molten rock becomes strong enough to cause an explosion, it erupts and starts to spew gases and rocks through the opening.
Volcanic eruptions can hurl hot rocks (sometimes called tephra) for at least 20 miles (32 km) and cause sideways blasts, lava flows, hot ash flows, avalanches, landslides and mudflows (also called lahars). They can also cause earthquakes, thunderstorms, flash floods, wildfires, and tsunamis. Sometimes volcanic eruptions can drive people from their homes forever.
Did you know…
- at least 20 volcanoes will probably be erupting as you read these words?! For example, Italy’s Stromboli has been almost continuously erupting over 2,000 years.
- there are an estimated 1 million volcanoes on the ocean’s floor that pump out roughly 3/4 of the lava reaching the earth’s surface?!
- the “Ring of Fire” that encircles the Pacific Ocean has about 450 historically active volcanoes?!
- more than 65 active or potentially active volcanoes exist in the U.S. and over 40 of them are in Alaska?!
- Yellowstone National Park actually sits on top of a supervolcano which erupted 3 times in the past 2 million years forming 3 massive calderas (or huge craters). The largest one — Yellowstone Caldera — is more than 60 miles (100 km) across. Some other large calderas formed by supervolcanoes are in Alaska, eastern California, Indonesia, Japan, New Zealand and South America.
Nature’s fury and beauty
Although volcanic eruptions can create havoc, misery and death with their fury, they can also provide spectacular views and beautiful photos. For example…
Lightning flashes around ash plume of the Puyehue-Cordon Caulle volcano chain near Entrelagos, Chile. (Carlos Gutierrez/Reuters)
An arching lava fountain, about 12 meters high, spurts from an early vent in the Puu Oo eruption of Kilauea Volcano, Hawaii. U. S. Geological Survey photo by Jim Griggs
Lightning over Sinmoedake peak REUTERS/Minami-Nippon Shimbun/Handout via Totallycoolpix.com
Have a great weekend! 🙂 j & B