Earth Sciences

A web of faults links the San Andreas Fault over a discontinuous 80-kilometer [50 mile] region in southern California. Carena et al. analyzed a gap in the famous fault line that runs from the Mojave Desert to the Coachella Valley and suggest that a network of seismically active faults likely connects the two strands of the 1,200-kilometer [750-mile] San Andreas Fault.

The researchers examined the three-dimensional geometry of the fault system in the complex region, reaching nearly 20 kilom

Part of the magnetic dust observed in Greenland ice cores may come from extraterrestrial sources, although most of the surface magnetism of ice also comes from iron-rich particles deposited by airborne dust. Lanci et al. used magnetic testing techniques on ice cores from central Greenland to trace the iron oxide content and total dust concentration in polar sources.

They suggest that measuring the magnetic strength of dust deposited on the icy surface can provide researchers an improved me

Researchers propose that an observed rise in the ice-melting rate during the summer and an extension of the melting periods through October in the Alps may be caused by global warming. Vincent et al. analyzed more than 50 years of data showing the annual mass balance changes for two glaciers in the Alps and report anomalous ice melting that was likely caused by climate change. The authors note an ice reduction of nearly half a centimeter [two-tenths of an inch] per day over the widely space

A worst-case scenario of climate change from the possible future release of submerged methane hydrates predicts catastrophic warming in the atmosphere and rising sea level similar to conditions that preceded the last ice age. Renssen et al. simulated the climate response from a massive release of methane from gas hydrates in the oceans, using a three-dimensional model to estimate the changes to the atmosphere-sea ice-ocean system over 2,500 years. Although the researchers do not speculate on

A new study examines the factors that would enable researchers to create a Martian version of the Global Positioning System widely used on Earth. Mendillo et al. investigated the planet’s ionospheric characteristics with radio signal data taken from the Mars Global Surveyor spacecraft and analyzed how local time, latitude, and solar cycle patterns would affect Mars’ electron content and contribute to errors in estimating exact locations on the planet’s surface. They note that,

Though the catastrophe that destroyed the dinosaurs’ world may have begun with blazing fire, it probably ended with icy darkness, according to a Purdue University research group.

By analyzing fossil records, a team of scientists including Purdue’s Matthew Huber has found evidence that the Earth underwent a sudden cooling 65 million years ago that may have taken millennia to abate completely. The fossil rock samples, taken from a well-known archaeological site in Tunisia, show that