Geology

Four urban sections of the San Andreas Fault system in Northern California have stored enough energy to produce major earthquakes, according to a new study of 'fault creep', and three fault sections, near Hayward, Rodgers Creek and Green Valley, are nearing or past their average recurrence interval. 


Phreatic eruption: Mount Ontake. Credit: EPA/Ministry of Land, Infrastructure

By Rebecca Williams, University of Hull

Mount Ontake, Japan’s second-highest volcano, erupted killing at least 31 people on September 27.

Since then, there has been feverish speculation about why tourists were on an active volcano and why the eruption wasn’t predicted.

Planetary geologists have speculated for decades that glaciers might once have crept through Valles Marineris, the 2,000-mile-long chasm that constitutes the Grand Canyon of Mars.

Using satellite images, astronomers have identified features they say might have been carved by past glaciers as they flowed through the canyons but those claims have remained highly controversial and contested. 

Now, a joint team from Bryn Mawr College and the Freie Universitaet Berlin has identified what could be the first mineralogical evidence of past glaciers within the Valles Marineris: a layer of mixed sulfate minerals halfway up the three-mile-high cliffs of Ius Chasma at the western end of the canyon system.

Volcano season. Some think it's the time of the year. Credit: EPA

By Robin Wylie, University College London


Landslides on Mars typically have runout distances much larger than equivalent features on Earth, and therefore can interact with older landforms that are distal to the failure scarp.

Regardless of the exact formation mechanism of these landslides, it is evident that their combined large area and relatively well constrained formation age can be exploited to better understand the evolution of coincident features, particularly if those features have been modified since the landslide event.


Credit: Image of map courtesy of the USGS and composite image by Patricia Waldron

By: Patricia Waldron, Inside Science

(Inside Science) -- People living in Afghanistan have mined precious gems from their land, such as lapis lazuli, since the times of the Egyptian pharaohs. But modern analyses of the country's mineral deposits show that the Afghan people have barely scratched the surface of their mineable wealth.

The 500 million years after Earth formed were not the hot, lava-filled Hell commonly portrayed, it may have had oceans, continents and active crustal plates - a lot like we have today.

This alternate view of Earth's first geologic eon, called the Hadean, gets support from the first detailed comparison of zircon crystals that formed more than 4 billion years ago with those formed contemporaneously in Iceland, which has been proposed as a possible geological analog for early Earth.

A tiny fragment of Martian meteorite 1.3 billion years old contains a 'cell-like' structure, which investigators say once held water, according to findings published in Astrobiology.

While investigating the Martian meteorite, known as Nakhla, Dr. Elias Chatzitheodoridis of the National Technical University of Athens found an unusual feature embedded deep within the rock. In a bid to understand what it might be, he teamed up with long-time friend and collaborator Professor Ian Lyon at the University of Manchester. 

American cars didn't cause all climate change, no matter what you may have read. Around 13,000 years ago, a sudden, catastrophic event caused drastic climate change and much of the Earth was plunged into a period of cold climatic conditions and drought. This drastic climate change, now called the Younger Dryas, coincided with the extinction of Pleistocene megafauna, such as the saber-tooth cats and the mastodon, and resulted in major declines in prehistoric human populations, perhaps including the termination of the Clovis culture in America.

By tracking seismic shifts, researchers say they may be able to predict a major quake off the coast of Istanbul.

When a segment of a major fault line goes quiet, it can mean one of two things - an inactive “seismic gap” which is the result of two tectonic plates placidly gliding past each other, or the seismic gap may be filled by an earthquake after quietly building tension for decades.

Researchers say they have found evidence for both types of behavior on different segments of the North Anatolian Fault — one of the most energetic earthquake zones in the world. The fault, similar in scale to California’s San Andreas Fault, stretches for about 745 miles across northern Turkey and into the Aegean Sea.