Taxonomy term

november 2014

Russian earthquake ruptures superfast and deep

A “superfast” magnitude-6.7 earthquake was detected off the coast of Kamchatka, Russia, in May. The earthquake, called a “supershear” quake, is one of a handful of superfast earthquakes noted by researchers over the years, but this is the first identified at such great depth.

24 Oct 2014

New lunar research answers old questions, poses others

From its close perch in the sky, the moon has long mystified artists, lovers and scientists. Now a quartet of recent papers — all of which touch on the moon’s violent birth and turbulent infancy — may help scientists put two long-standing lunar mysteries to rest, while deepening a third enigma and suggesting a speculative solution to a fourth.

23 Oct 2014

Past penguin populations not dependent on ice extent

Penguins’ lives revolve around ice, so it seems they might be particularly vulnerable to changing ice conditions and ice loss. But a new study charting the rise and fall of penguin populations over the last 30,000 years suggests that past populations have actually increased during times of climate warming and retreating ice.

21 Oct 2014

We're all living in the global aftershock zone

Can a large earthquake trigger another quake hundreds or even thousands of kilometers away? The answer, scientists say, appears to be yes, but when it happens is far from predictable. How does such dynamic triggering affect global earthquake hazards? Perhaps the whole world should be considered an aftershock zone.

19 Oct 2014

Remote triggering of ice quakes

On Feb. 27, 2010, a magnitude-8.8 earthquake struck the subduction zone off the coast of Chile. The resulting Rayleigh surface waves rippled around the world, triggering small earthquakes in many different tectonic settings, including Antarctica. As the surface waves moved across the white continent, a third of Antarctic seismic stations reported shaking coming from so-called “ice quakes.”

19 Oct 2014

Triggered tremor along the San Andreas Fault

The San Andreas Fault (SAF) in California is one of the most active in the U.S., but the 1,300-kilometer-long strike-slip fault seems to only be susceptible to small-scale dynamic triggering. After the magnitude-9 Tohoku quake in Japan in 2011, the SAF experienced an elevated incidence of tremor up and down its length. The tiny tremors were recorded at depths between 16 and 30 kilometers, below the fault’s seismogenic zone.

19 Oct 2014

Casting a seismic shadow

In the week or two before the magnitude-8.6 Indian Ocean earthquake in 2012, Earth was unusually quiet, with few large quakes over magnitude 5. Afterward, seismic activity all over the globe was elevated for more than a week. Then, suddenly, global seismicity dropped off precipitously: Beginning two weeks after the mainshock, no earthquakes of magnitude-6.5 or greater occurred for 95 days.

19 Oct 2014

Harpooning space debris

Harpooning was first used to spear fish, and later whales, but has yet to be used in space. Now, the European Space Agency (ESA) is considering the ancient technique to capture rogue satellites interfering with important orbits.

18 Oct 2014

Mercury formed by hit and run?

The solar system was once as busy as a store parking lot on Black Friday. Collisions were common in the early days, and new evidence of a hit-and-run scenario may explain some of Mercury’s peculiarities.

17 Oct 2014

Clues to limestone weathering written in Western Wall

Builders and masons take note: When it comes to the durability of limestone, grain size matters. New research combining field and lab data shows that fine-grained limestone is more susceptible than its coarser-grained cousins to a one-two punch of chemical and mechanical weathering. The findings, which arose in part from observations of Jerusalem’s historic Western Wall, could have implications for Earth’s carbon cycle and landscape — as well as for architectural preservation.

16 Oct 2014