How much do we know about Stonehenge? Less than we think. And what has Stonehenge got to do with the Ice Age? More than we might think. This blog is mostly devoted to the problems of where the Stonehenge bluestones came from, and how they got from their source areas to the monument. Now and then I will muse on related Stonehenge topics which have an Ice Age dimension...
THE BOOK Some of the ideas discussed in this blog are published in my new book called "The Stonehenge Bluestones" -- available by post and through good bookshops everywhere. Bad bookshops might not have it.... To order, click HERE
Tuesday 6 December 2022
Vatnajökull -- Sentinel satellite image
This is a fabulous Sentinel satellite image of Vatnajökull in Iceland-- published by the Copernicus project. If I had still been teaching glacial geomorphology, I think I could have based a whole course of lectures on this one image..........
2 comments:
Philip Denwood
said...
Very impressive. What is the difference between the white in the middle and the grey round the edges?
The white is the higher part of the ice cap, still snow covered after the winter. The edge of the white area is somewhere near the equilibrium line, marking the transition between the accumulation zone (above) and the ablation zone (below). So the grey area shows exposed ice. If you click on the image you can see some fantastic detail of the structures in the ice and the many thousands of annual layers. Vatnajökull is unusual in that many of the surfaces have ash deposits on them, derived from the eruptions of the nearby volcanoes.
2 comments:
Very impressive. What is the difference between the white in the middle and the grey round the edges?
The white is the higher part of the ice cap, still snow covered after the winter. The edge of the white area is somewhere near the equilibrium line, marking the transition between the accumulation zone (above) and the ablation zone (below). So the grey area shows exposed ice. If you click on the image you can see some fantastic detail of the structures in the ice and the many thousands of annual layers. Vatnajökull is unusual in that many of the surfaces have ash deposits on them, derived from the eruptions of the nearby volcanoes.
Post a Comment