GMPV
Geochemistry, Mineralogy, Petrology & Volcanology

Magma

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]

Living with volcanic gases

Living with volcanic gases

Professor Tamsin Mather, a volcanologist in Oxford’s Department of Earth Sciences reflects on her many fieldwork experiences at Masaya volcano in Nicaragua, and what she has learned about how they effect the lives of the people who live around them.  Over the years, fieldwork at Masaya volcano in Nicaragua, has revealed many secrets about how volcanic plumes work and impact the environment, ...[Read More]

A little fracture can go a long way: How experiments illuminate our understanding of volcanic eruptions

A little fracture can go a long way: How experiments illuminate our understanding of volcanic eruptions

What controls how violently a volcano erupts? Stratovolcanoes like Mount St Helens (USA), Gunung Merapi (Indonesia), or Volcán de Colima (Mexico) tend to erupt in two distinct ways: effusively and/or explosively. Effusive eruptions are eruptions where lava is extruded without any major explosions. Although effusive eruptions can be dangerous, at stratovolcanoes they tend to be restricted to volcan ...[Read More]