Ice ages come and go. So do pulses of volcanic eruptions on land and at sea, maybe, on roughly the same time scale. Could the two be related? A recent two-week oceanographic expedition aimed to find out. The overarching hypothesis: As water accumulates on land in the form of massive ice sheets, the pressure of the overlying ice puts a lid on volcanoes. A corresponding drop in sea level allows volcanic vents on the seafloor to let loose. Then, when the planet warms, causing ice to melt and sea levels to rise, hydrothermal venting is suppressed, while volcanoes on land become more active.
January 28, 2015
January 20, 2015
Volcanoes can have multiple personalities, peaceful one minute, explosive the next. A geologist who has untangled these complicated states on land and at sea, improving our ability to see deadly eruptions coming, will receive the 2015 Vetlesen Prize. Stephen Sparks, a volcanologist at the University of Bristol, will be awarded a medal and $250,000 at a ceremony in New York in June.
December 16, 2014
In Portuguese, fogo means fire, and for hundreds of years, Fogo volcano in the Cape Verde islands off Senegal has lived up to its name. It has spouted off every 20 years or so, at least as far back as 1460 when the Portuguese settled here. Nearly 20 years after its last eruption, in 1995, Fogo awoke on the Sunday after Thanksgiving. Within a week, it had buried two villages high in Fogo’s caldera – Portela and Bangaeira – under lava, leaving 1,200 people homeless.
February 17, 2014
Terry Plank got hooked on volcanoes when her professor at Dartmouth took the students to Costa Rica and let them have lunch on Arenal, a famous volcano that was in the process of erupting. “They gave us each a pineapple and a can of tunafish and we had to figure out how to eat this stuff with our Swiss Army knives while sitting on a lava flow…It just looked like black rock, but every once in awhile a boulder at the end would fall off and you’d see it was completely red inside. And it made all these cool sounds and you’d feel these little earthquakes… It was totally cool. How could you not like that?”
December 12, 2013Guleed Ali pauses to study his notebook, standing on a steep slope covered in gray volcanic ash and desert brush, high above the present-day shore of Mono Lake in eastern California. He looks across the slope to where, a few hundred yards away, a gash of lighter gray sediment cuts across the hill, then disappears. The exposed sediment is history: A record of deposits left by Mono Lake when it stood far higher than today.
September 11, 2013
Naturally occurring arsenic pollutes wells across the world, especially in south and southeast Asia, where an estimated 100 million people are exposed to levels that can cause heart, liver and kidney problems, diabetes and cancer. Now, scientists working in Vietnam have shown that massive pumping of groundwater from a clean aquifer is slowly but surely drawing the poison into the water. The study, done near the capital city of Hanoi, confirms suspicions that booming water usage there and elsewhere could eventually threaten millions more people. The study appears in the current issue of the leading journal Nature
July 31, 2013
If some volcanoes operate on geologic timescales, Costa Rica’s Irazú had something of a short fuse. In a new study in the journal Nature, scientists suggest that the 1960s eruption of Costa Rica’s largest stratovolcano was triggered by magma rising from the mantle over a few short months, rather than thousands of years or more, as many scientists have thought. The study is the latest to suggest that deep, hot magma can set off an eruption fairly quickly, potentially providing an extra tool for detecting an oncoming volcanic disaster.
July 09, 2013
A new study in the journal Nature provides fresh insight into deep-earth processes driving apart huge sections of the earth’s crust. The process, called rifting, mostly takes place on seabeds, but can be seen in a few places on land—nowhere more visibly than in the Afar region of northern Ethiopia. (See the slideshow below.) Here, earthquakes and volcanoes have rent the surface over some 30 million years, forming part of Africa’s Great Rift Valley. What causes this, and does it resemble the processes on the seafloor, as many geologists think?
August 09, 2011
Researchers returning from a cruise some 250 miles off the coast of Oregon have reported seeing a volcanic eruption on the seafloor that they accurately forecast five years ago—the first successful prediction of an undersea eruption. The event took place at Axial Seamount, one of the most active and intensely studied undersea peaks in the world.
February 18, 2011
Northern New Jersey, southern Connecticut and environs are not necessarily where one would expect to explore the onetime extinction of much life on earth, and subsequent rise of dinosaurs. But it turns out to be a pretty good place to start. Underlying the exurbs are geological formations left by three giant episodes of volcanism starting around 200 million years ago, and intervening layers of sediments that built up in the interims between massive lava flows.
November 03, 2010
Scientists have long known that large volcanic explosions can affect the weather by spewing particles that block solar energy and cool the air. Some suspect that extended “volcanic winters” from gigantic blowups helped kill off dinosaurs and Neanderthals...
August 19, 2010
Scientists are in the early stages of building a fiber optic network on the seafloor for observing, in real time, deep-sea hydrothermal vents---places where super-heated water and minerals spew from Earth's crust offering clues about how life on the planet may have began.
January 06, 2009
But Global Warming May Have Helped Override Some Recent Eruptions
Climate researchers have shown that big volcanic eruptions over the past 450 years have temporarily cooled weather in the tropics—but suggest that such effects may have been masked in the 20th century by rising global temperatures
January 05, 2005
The Maurice Ewing, owned by the National Science Foundation and operated by the Lamont-Doherty Earth Observatory (L-DEO), is the only research vessel devoted to obtaining images of the deep earth for fundamental earth science research.
|Clocking the Run-up to Volcanic Eruptions|
|Upper Mantle Oxidation State Implications for the Asthenosphere||Earth Science Colloquium|
|Volcanoes and Vents: A Hidden World Beneath the Sea|
|LDEO Open House||Welcomes Science and Nature Lovers of All Ages|
|Water in Arc Magmas||Part of the Earth Science Colloquium Series|