HAZARDS

hazards

Scientists get rare opportunity to monitor caldera collapse in real time

Many of the most catastrophic volcanic eruptions in history have something in common: caldera collapse — the formation of a large hole by the collapse of a volcano’s peak associated with the emptying of the magma chamber. But these events are rare. So, in August 2014, when Bárdarbunga Volcano in central Iceland erupted, it gave scientists the unique opportunity to study a caldera collapse in real time.

17 Oct 2016

Everything's bigger in Texas, including the Wink sinkholes

Residents of the neighboring West Texas towns of Wink (population 940) and Kermit (population 6,000) have had decades to get used to a pair of large sinkholes that opened a couple of kilometers apart between their towns, the first in 1980 and the second in 2002. But according to a new study, the ground around the two holes is subsiding and unstable, opening up the possibility that they could collapse into one giant sinkhole.

10 Oct 2016

Lack of afterslip in Nepal hints at mounting tensions

On April 25, 2015, a magnitude-7.8 earthquake struck Nepal, northwest of Kathmandu, damaging much of the capital city, flattening surrounding villages and killing more than 8,000 people. The quake’s hypocenter was relatively shallow, only 15 kilometers below ground on a fault that’s part of the Main Himalayan Thrust. Yet the displacement didn’t rupture all the way to the surface, indicating that only part of the fault slipped. Now, in a new study looking at how the fault continued to move following the 2015 event, researchers have found that the shallower section of the fault is likely still locked — and potentially loaded for another earthquake.

02 Oct 2016

Kilauea increases asthma risk

Kilauea may be best known for its picturesque red lava flowing into the ocean, but new research presented this week at the Geological Society of America annual meeting in Denver, Colo., suggests that locally, the volcano may be known for something more dangerous: asthma. The new study links gaseous eruptions from the Hawaiian volcano to increased asthma risk for those living downwind, especially children.

 
28 Sep 2016

Benchmarks: September 8, 1900: Massive hurricane strikes Galveston, Texas

Everyone said it couldn’t happen. City leaders saw no need for an expensive seawall, trusting local meteorologist Isaac Cline when he claimed that it was “impossible for any cyclone to ... materially injure the city.” And so, on the morning of Sept. 8, 1900, when the skies over Galveston, Texas, darkened with rain and the winds blew strong, residents of this booming barrier island community believed their city could weather any storm. By the next morning, the city lay in ruin, blasted by a Category-4 hurricane that killed an estimated 10,000 people — a quarter of the island’s population — and more than the combined death tolls of all other landfalling U.S. hurricanes since.

08 Sep 2016

Peeling North American Plate causing East Coast earthquakes

On Aug. 23, 2011, a magnitude-5.8 earthquake struck near Mineral, Va., shaking the Piedmont region and damaging several historic buildings in Washington, D.C. The quake caught many people by surprise because the eastern U.S. lies in the interior of the North American Plate, more than 1,500 kilometers from the nearest plate boundary. In a new study, researchers peering beneath the southeastern portion of the North American Plate may have found an explanation for why parts of the region experience more quakes than expected.

31 Aug 2016

Firefighting gets a leg up from earthquake sensor networks

Seismic networks monitor ground motion in earthquake-prone regions like California and Nevada. Now, they may also help combat other natural hazards like wildfires, which are especially common in drought-stricken western states where parched landscapes create ideal conditions for fires to spread.

19 Aug 2016

Helium escape may help predict volcanic activity

Europe’s tallest active volcano, Mount Etna, rises 3,300 meters above the island of Sicily, which lies just off the coast of Italy’s “toe.” Within 100 kilometers of more than 3 million people, Etna frequently rumbles and occasionally belches. As recently as last May, explosions accompanied lava fountains and ash erupted from one of the volcano’s craters over several days. This was just one of many eruptions in a long line of events, with historical documents dating similar outbursts back to 1500 B.C. Scientists cannot pinpoint when Etna will next erupt, but in a new study in Geology, researchers have identified a clue that may help them better understand how the volcano’s inner plumbing system changes just prior to an eruption.

17 Aug 2016

Vibrations make large rocky landslides flow like water

There is a rule of thumb in geology for how far a landslide will run out: Most landslides travel roughly twice the vertical fall distance from where they fall off their parent slope. But certain types of dry landslides, called sturzstroms, can travel 20 to 30 times farther, without water or mud to lubricate the flow. Scientists have long hypothesized about exactly how this occurs, and new computer models seem to back up their hypotheses: that vibrations generated by dry rocky landslides can cause the slides to flow like a fluid and spread out across surprisingly large areas.

06 Aug 2016

Sand shouldn't stand in for volcanic ash in jet engine tests

In 2010, the ash cloud produced by Iceland’s Eyjafjallajökull Volcano grounded trans-Atlantic and European flights for six days due to fears that the high-flying ash could damage — and stall — jet engines. The eruption, which snarled international air travel and led to billions in economic losses, spotlighted the need for more study of the effects of volcanic ash on jet engines. Many such studies have been done using sand as a convenient stand-in for ash. But a new study shows that some types of volcanic ash behave very differently from sand at high temperatures, suggesting sand is an inadequate analogue.

31 Jul 2016

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