GMPV
Geochemistry, Mineralogy, Petrology & Volcanology

Magma

Happy Birthday Mama Etna!

Happy Birthday Mama Etna!

18 May 1971. This date may not mean anything to you at the moment, but it represents a very special day for the evolution of Mount Etna, leaving a deep mark in the recent eruptive activity of the volcano. Exactly 50 years ago, Mount Etna saw the birth of what, only a short time later, was to become the most active crater of the last decades: “The South-East Crater”, the fourth child of ...[Read More]

How do crystal aggregates form in magma chambers?

How do crystal aggregates form in magma chambers?

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]

Are mantle melts heterogeneous on a centimeter scale?

Are mantle melts heterogeneous on a centimeter scale?

The mantle makes up the majority of the volume of the Earth, but there is still a lot about it that we don’t understand. This is because we can’t observe it directly – forget ‘Journey to the center of the Earth’ – even our deepest drill holes (about 12 km deep) are merely tickling the surface of the planet (about 6400 km to the center). Most of what we know abou ...[Read More]

Building a lava dome: one block at a time

Building a lava dome: one block at a time

Lava domes form when lava is extruded from a volcanic vent, but is too viscous to flow far away. Think of thick treacle that does not flow as easily as runny honey, and so when it is extruded, it forms a “lava pile” around the vent. Lava domes commonly form within the crater of a larger volcano (e.g. Mt. St. Helens), but can also stand alone or form part of a “dome complex”. A lava dome can take o ...[Read More]