In the first part
of this look at magma chambers, I talked about some of the processes that dominate what goes on beneath an active volcano. The twin actions of fractionation and assimilation were what preoccupied the early researchers, however more recently we've realised things are a little more complicated than that. In this part I want to take a closer look at some of those intricacies.
Planet Earth: Extreme Beauty – Extreme Danger
The moon has no global magnetic field yet Apollo astronauts found magnetized rocks on the lunar surface.
A new hypothesis proposes a mechanism that could have generated a magnetic field on the moon early in its history. The 'geodynamo' that generates Earth's magnetic field is powered by heat from the inner core, which drives complex fluid motions in the molten iron of the outer core. The moon is too small to support that type of dynamo but the researchers write in Nature that an ancient lunar dynamo could have arisen from stirring of the moon's liquid core driven by the motion of the solid mantle above it.
This post is the first of a new series I plan to write, on the techniques used to study and monitor volcanoes. The reason science is the best method we have of investigating the world around us is not so much what we know, but how we know it. I thought I'd start with a technique that always amazes me; we can measure centimetres of ground deformation over an area of many square kilometres, from an altitude of 800 km. Interferometric Synthetic Aperture Radar, InSAR for short.
Want to get people excited about space exploration? Continue to use D&D-style names like Tharsis Tholus for geological features on Mars and every young man in the world will want to visit.
What goes on underneath the most deadly volcanoes? As my PhD investigates the processes that occur below the ground on Santorini, I thought I would try to explain some of what goes on under every active volcano.
The Hayward fault runs smack dab through the UC Berkeley football stadium; it is being retrofitted this year.
In the last week, there have been 3 earthquakes on or near the campus, with a magnitude of 4.0 (last Thursday afternoon), 3.8 (last Thursday evening), and 3.6 (this morning).
On a traditional GPA scale, 4.0 is a perfect grade score of straight A's. So the mean (and median) GPA for UC Berkeley is now 3.8.
What do you say to that, San Andreas Fault and Stanford University? Unwilling or unable to compete (or both)?
Every 100,000 years a "super-eruption" of a major volcanic system occurs - one of the most catastrophic natural events on Earth - yet it's hard to know what triggers these violent explosions.
The eruption of super-volcanoes dwarfs the eruptions of recent volcanoes and can trigger planetary climate change by inducing Ice Ages and other impacts. One such event was the Huckleberry Ridge eruption of present-day Yellowstone Park about two million years ago, which was more than 2,000 times larger than the 1980 eruption of Mount St. Helens in Washington. These super-eruptions are second only to meteor strikes in their impact.
You can thank the stretching of continents and the oceans that filled those newly created basins for the Earth we know today. Rifting is one of the fundamental geological forces that have shaped our planet. But rifting involves areas deep below the Earth's surface so scientists have been unable to understand fully how it occurs.
Using one of the most sensitive neutrino detectors on the planet, the Borexino instrument, an international team are measuring the flow of solar neutrinos reaching Earth more precisely than ever before.