GMPV
Geochemistry, Mineralogy, Petrology & Volcanology

Volcanoes

The Volcano & the Ash cloud: Eyjafjallajökull eruption 11 years later

April 7, 2021
In the foreground there is a farm with a backdrop of a volcano is emitting large amounts of ash into the air.
The Ash cloud billowing out of Eyjafjallajökull in southern Iceland, April 16th 2020 (Source Encylopedia Britanica, Brynjar Gauti/AP)

11 years on from the infamous eruption and ash cloud that shut down the European airspace, there are parallels between current travel restrictions and another Icelandic eruption that’s currently in the news. 11 years ago the now infamous eruption of Eyjafjallajökull occurred. I remember that one, the ash cloud, right? Yes, that’s the one. The one that was all over the news, with stunning images of ...[Read More]

Ask us (almost) anything: how is tuff formed?

, and August 25, 2020
Ask us (almost) anything: how is tuff formed?

Tarun Goswami, an archaeologist from India, asks: How is a tuff formed? and more specifically… Why do some deposits have more ash than others? We are paraphrasing – the questions are specifically about the tuffs formed in the Toba supereruption. So… you asked, we answer! First of all, modern definitions generally describe a tuff as a volcaniclastic rock composed of solid volcanic ...[Read More]

Can limestone digestion by volcanoes contribute to higher atmospheric carbon dioxide levels?

October 28, 2019
Can limestone digestion by volcanoes contribute to higher atmospheric carbon dioxide levels?
Degassing at Merapi volcano, Indonesia. Source: GFZ.

By Frances Deegan and Ralf Halama Carbon – the element on everyone’s lips. Carbon is unquestionably one of the most important elements on Earth – terrestrial life is carbon-based and so are many of our energy sources. From the perspective of a human time-scale, biological and anthropogenic (caused by human activity) carbon fluxes are very important (e.g. through industrial activity and burni ...[Read More]

How do crystal aggregates form in magma chambers?

September 5, 2019
How do crystal aggregates form in magma chambers?
EBSD map of chromite crystals colored according to the orientation, showing random orientations.

By Penny Wieser (PhD student at the University of Cambridge) Clues into the inner workings of volcanoes can be gleamed from material which is erupted at the surface, or that which solidified at depth in the crust. Just before eruption, three main phases are present: a gas phase (containing water, carbon dioxide, sulphur, chlorine etc), a liquid melt phase (the magma), and a solid phase (consisting ...[Read More]