Category Archives: subduction

Some facets of the Geology of Diamonds

Originally published on the Scientific American guest blog. Geoscientists can’t say if diamonds are forever, but they can say that some are already billions of years old. They form in a place we’ll never reach: the deep earth, hundreds of … Continue reading

Categories: diamonds, geochemistry, impacts, subduction

A harder look at the geology of diamonds

My recent post about diamonds was a rapid romp through some of the most marvellous things earth scientists have discovered about them. In the interests of keeping the casual reader engaged I left out many things. If this left you with … Continue reading

Categories: diamonds, eclogites, subduction

The Grampian / Taconic orogeny in Ireland – when arcs attack

Ever since the plate tectonic paradigm-shift of the 1960s, geologists have strived to understand ancient rocks in terms of the movements of plates. The geology of north-western Ireland can be explained by what happened when a subduction zone ran out … Continue reading

Categories: Ireland, metamorphism, mountains, subduction, tectonics

How to make a rock from scratch

“If you wish to make an apple pie from scratch, you must first invent the universe.” Carl Sagan. I have a handsome piece of rock in my hand. How did it come to be, how was it made? A perfectly … Continue reading

Categories: geochemistry, metamorphism, subduction