Geochemistry, Mineralogy, Petrology & Volcanology

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

EGU Guest blogger October 28, 2019

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]

#mineralmonday: tiptopite

Mike Jollands September 16, 2019

#mineralmonday: your weekly* dose of obscure mineralogy, every Monday** [*not guaranteed; **or possibly Tuesday-Sunday] What is it? Tiptopite: K2Na1.5Ca0.5Li3Be6(PO4)6(OH)2•(H2O) What’s it made of? Take a deep breath and recite after me: potassium, sodium, calcium, lithium, beryllium, phosphorus, oxygen and water (H2O). Is it pretty? Yes, it’s a beautiful fibrous mineral. You wouldn&# ...[Read More]

How do crystal aggregates form in magma chambers?

EGU Guest blogger September 5, 2019

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]

#mineralmonday : sengierite

Mike Jollands August 4, 2019

#mineralmonday: your weekly* dose of obscure mineralogy, every Monday** [*not guaranteed; **or possibly Tuesday-Sunday] What is it? Sengierite: Cu2(UO2)2V2O8.6(H2O) What’s it made of? A few useful metals – copper (Cu), vanadium (V), uranium (U), plus oxygen (O) and water (H2O). So by ‘useful’ you mean ‘radioactive’? Pretty much. The main reason people have been ...[Read More]