My cup of tea is sitting nearby, the rocket-fuel for the mind is sitting in a piece of man-made metamorphic rock and lying on the saucer is a humble object that bears mute witness to ancient, earth-changing events. Tea in England is typically taken with milk and sometimes with sugar – lots if it’s “builders’ tea” – and a small… Continue reading Stirring tales from the deep past.
Category: geochemistry
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 from melting of the mantle rocks – is now solid, so ‘tasting it’ involves dissolving… Continue reading Tasting the earth: mantle geochemistry
The Himalaya: mountains made from mountains
Good building stones get reused. Sometimes the only traces of very old buildings are their stones, built into more modern ones. It’s the same with rocks and mountain belts. Stone that now forms parts of the Himalaya was once part of a now-vanished mountain range. The Himalaya were formed by the collision between the Indian… Continue reading The Himalaya: mountains made from mountains
Radioactivity and the earth (and moon?)
We tend to think of radioactivity as an artificial thing; some argue that the first nuclear explosions in 1945 should mark the start of a new human-dominated geological epoch called the Anthropocene. These man-made explosions have left distinctive radioactive traces that may well outlive us all. It turns out that natural radioactivity, even fission reactions,… Continue reading Radioactivity and the earth (and moon?)