Taxonomy term

volcanic eruption

Lava shaped Lake Tahoe

With its preternaturally clear blue waters, Lake Tahoe is tranquil today, but the deep lake straddling the border of California and Nevada was once the site of repeated lava flows. In a new study, researchers used radiometric argon dating to describe how episodes of volcanism created the landscape around the largest alpine lake in North America.

21 May 2018

Chemical tipping point triggers eruptive transitions

During an eruption, some volcanoes vacillate unpredictably between effusive and explosive behavior. New research has identified a chemical tipping point in some magmas that may trigger the transition between such mild and violent eruptive cycles.

 
02 Apr 2018

Seismic patterns help forecast eruptions from quiet stratovolcanoes

Earth is home to more than 1,500 potentially eruptive volcanoes on land, each with a unique character and history. Predicting when and how a particular volcano may erupt is notoriously difficult, in large part because each eruption is unique. Recent work tracking pre-eruptive seismic behavior beneath two dozen reawakened volcanoes has revealed a distinctive pattern that seismologists may be able to use to assess when — and how violently — a rumbling volcano could blow its top.

24 Nov 2017

How long will the lava flow? Predicting eruption durations with satellite monitoring

If you live near a lava-spewing volcano, it could be helpful to know just how long molten rock might flow during a fiery eruption. In a new study, scientists report that they can calculate how long lava-flowing eruptions might last based on satellite data.

27 Oct 2017

Limestone reservoirs boost volcanic carbon emissions

Volcanoes have been the main source of atmospheric carbon over Earth’s history, with some types of eruptions injecting more carbon into the atmosphere than others. Arc volcanoes, for example, which form in chains along subduction zones, are responsible for up to two-thirds of all volcanic carbon emissions today, and have likely been major contributors for as long as they’ve existed. New research suggests a reason why: These volcanoes draw large amounts of carbon from limestone platforms found along many subduction zones. The finding has implications for how the volcanic carbon cycle affects climate over geologic timescales.

18 Oct 2017

Volcanism triggered end-Triassic extinction

The end-Triassic mass extinction exterminated up to three-quarters of all species on land and in the oceans 201 million years ago. This die-off opened up ecological niches and allowed for, among other changes, dinosaurs to diversify and spread across terrestrial ecosystems during the rest of the Mesozoic. Volcanism has long been implicated in the extinction, but whether it had a major impact on the planet at the time has remained unclear. In new research, scientists observed elevated mercury concentrations in extinction-aged rocks from around the world. Because volcanism is the main nonanthropogenic source of mercury in the environment, the findings suggest that volcanic activity was likely the main extinction trigger at the end of the Triassic.

21 Sep 2017

Glass shards reveal a fiery history in Ethiopia

Chains of volcanoes and a lava lake pepper the landscape of the Afar Triangle in northeastern Ethiopia, where eruptions and earthquakes are byproducts of the rifting that is literally ripping Africa apart, but recent eruptions have been docile. Now, scientists studying ash deposits from the last 40,000 years are showing that dangerous, explosive eruptions present an ongoing hazard, striking the region every 1,000 years on average.

18 Sep 2017

Earthquakes make volcanoes more — and less — gassy

Triggering of volcanic emissions by earthquakes has been observed since antiquity. The Roman naturalist and philosopher Pliny the Elder proposed the link as early as A.D. 77, and in “The Voyage of the Beagle,” Charles Darwin wrote about inland eruptions in Chile closely following an offshore earthquake in 1835. More recent statistical studies show that after large earthquakes, volcanic activity around the world increases. But the lack of robust monitoring equipment at most volcanoes has made it hard to quantify the relationship. In a new study, scientists demonstrate how satellites can be used to track changes in sulfur dioxide emissions from volcanoes after seismic events, offering a potential way to study the often elusive link between seismicity and volcanism.

25 Aug 2017

New global volcanic emissions map debuts

Volcanoes may not always be erupting ash or lava, but that doesn’t mean they’re not venting other materials. Many, in fact, continuously spew gases like carbon dioxide and sulfur dioxide into the air. In a new study, volcanologists compiled data tracking such releases, collected by NASA’s Aura satellite, into the first global map of volcanic sulfur dioxide emissions.

13 Jul 2017

Geologic Column: Volcanoes: Awesome and dangerous

Volcanoes and volcanic eruptions are a marvel of nature, but a beautiful visage can mask significant danger.
03 Jul 2017

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