Diamonds are Deeper

10 Mar 2018

William sent in this link - ... a large diamond dug up in South Africa contains calcium silicate perovskite trapped inside - a mineral not found on the surface of the Earth, we are assured. It is however abundant in the lower Mantle, we are told, but how did it reach the crust? According to a paper in Nature the mineral is highly unstable - unless trapped in a very strong container such as the diamond in question. This indicates, we are led to believe, the diamond itself must have migrated from deep under the surface of the Earth.

William also sent in the link, ... which may not be particularly terrifying at all. They are referring to the hole in the ground that has opened up north of Yakutsk. The permafrost has melted and the ground has sagged, opening up a huge crater. It has been going on for 50 years. It is now 100m deep and a km in length and has provided a window on Pleistocene flora. There follows a lot of hype about global warming.

Finally, Robert sent in the link ... which is a nice piece of scepticism concerning some recent science stories. It begins with Plate Tectonics and subduction and suggests there are a lot of theories subducting. It then homes in on the dry glaciers of the Gobi desert (see a few days ago). They are not impressed with the fact no glaciers existed during the Late Glacial Maximum, but may have done thousands of years prior to the LGM. It seems that cold alone is not sufficient to form glaciers. Next they move on to a storm in 2013 that was strong enough to move house sized boulders on the west coast of Ireland. They say that these are usually blamed on tsunami waves but clearly storms can do the same. They also mention a couple of other subjects too.