Author Archives: Metageologist

Hot spot volcanoes: no plumes required?

It’s a simple and well-known picture. Volcanoes form either at plate boundaries due to subduction or inside plates due to mantle plumes. Invoking plumes – columns of hot rock rising from deep in the mantle – is an awfully useful way of explaining … Continue reading

Categories: Deep earth

Great Geology in Google Maps: dunes

Google Maps is a great resource, particularly in satellite view. My favourite way to enjoy it is via the Chrome extension “Earth View from Google Maps“. This pops up a gorgeous image in every new tab. Many show human landscapes, but … Continue reading

Categories: Great Geology in Google earth, sediments

Tasting the earth: mantle geochemistry

If seismologists listen to the earth then geochemists taste it. Like experts blind-tasting a glass of wine and recognising where it came from, geochemists studying the deep earth aim to find out where a particular liquid came from. Their liquid – basaltic magma formed … Continue reading

Categories: Deep earth, geochemistry

Metamorphic petrology under stress: round 2

Back in August I wrote about an extremely important paper by John Wheeler of Liverpool University called “Dramatic effects of stress on metamorphic reactions”. This uses a theoretical approach to show that differential stress (squashing rocks) is a very important … Continue reading

Categories: metamorphism