Geology

On April 25th, a 7.8-magnitude earthquake struck Nepal, claiming over 5,000 lives and affecting millions more. Relief efforts are under way and satellite imagery is helping to visualize the damage but radar images from the ESA Sentinel-1A satellite showed why Nepal’s capital, Kathmandu, experienced so much damage

The maximum land deformation, shown in before and after pictures, is 8 miles away. The two acquisition dates lead to rainbow-colored interference patterns in the combined image, known as an ‘interferogram’, enabling scientists to quantify the ground movement.

Some of the ocean's underwater volcanoes did not erupt from hot spots in the Earth's mantle but instead formed from cracks or fractures in the oceanic crust, which would help explain the spectacular bend in the famous underwater range known as the Hawaiian-Emperor seamount chain, where the bottom half kinks at a sixty degree angle to the east of its top half. 

It has long been accepted that as the Earth's plates move over fixed hot spots in its underlying mantle, resulting eruptions create chains of now extinct underwater volcanoes or 'seamounts'.

Can earthquakes ever be predicted? This question is timely after the magnitude 7.8 earthquake that struck Nepal recently. If authorities had more warning that the earthquake was coming, they may have been able to save more lives.

While Nepal is a documented area of previous seismic activity, at the moment there is no technique that provides predictions of sufficient clarity to allow for evacuations at short notice. So if we cannot predict these events now, are there avenues of research to provide useful predictions in the future?

In the ongoing conflict between science and young Earth creationism, evolution is usually a main point of contention. The idea that all life on Earth evolved from a common ancestor is a major problem for young Earth creationists. 

As a geologist, though, I think that the rocks beneath our feet offer even better arguments against young Earth creationism. For the young Earth creationist model doesn’t square with what you can see for yourself. And this has been known since before Darwin wrote a word about evolution.

Seismologists have discovered a massive magma reservoir beneath the Yellowstone supervolcano in Wyoming, US, that suggests its volcanic system could be more than 5.6 times larger than was previously thought.

The Calbuco volcano, a 2,000 meter peak in southern Chile, sent a column of ash about 15 kilometers skywards twice on the night of April 22 and early the following morning. 

As the risk of deadly flows of ash and hot air was immediate, a 20 kilometer radius evacuation zone was declared.

The event was spectacularly visible from Puerto Montt, a city of nearly 200,000 inhabitants, only 30 km away. It seems to have begun within barely five hours of warning signs being first detected by local seismometers.

In 2013, Typhoon Haiyan killed more than 6,000 people and destroying nearly $3 billion worth of property in the Philippines. While the country is still recovering from the storm, researchers have found that an aquifer on the island of Samar inundated with salt water by the storm surge could remain undrinkable for up to 10 years - a second aquifer on the island that was also inundated has recovered much more quickly.

Geology and infrastructure play key roles in determining whether aquifers that provide drinking water are inundated with seawater during a typhoon or hurricane and how long the contamination lasts.


New details of a nightmare period on Earth with surface conditions as frigid as present-day central Antarctica at the equator have been revealed thanks to the publication of a study of ancient glacier water.

The research, by an international team led by Daniel Herwartz, is published in the journal Proceedings of the National Academy of Sciences and shows that even tropical regions were once covered in snow and ice.

The same processes that determined how continents were generated on Earth more than 2.5 billion years ago have continued within the last 70 million years - and they profoundly affect the planet's current life and climate.

A new study details how relatively recent geologic events , namely volcanic activity 10 million years ago in what is now Panama and Costa Rica, hold the secrets of the extreme continent-building that took place billions of years earlier. This provides new understanding about the formation of the Earth's continental crust, the masses of buoyant rock rich with silica, a compound that combines silicon and oxygen. 

One canyon on Earth has two mouths - but that is not the only mystery.

First formally documented by western explorers mapping the Colorado Territory in the 1800s, Unaweep Canyon is a puzzling landscape and so it has inspired numerous scientific hypotheses for its origin. A new paper published in Geosphere by Gerilyn S. Soreghan and colleagues brings together old and new geologic data of this region to further the hypothesis that Unaweep Canyon was formed in multiple stages.