Studland Bay. Looks all peaceful now, but if you take a closer look at the cliff you will see this... The lighter coloured rock at the bottom is the last strata of the Cretaceous period, the time of the Dinosaurs. The shattered flint and dark sediment above is the result of an asteroid about 6 miles across hitting on the other side of the world.... (Pic curtesy of Google Earth) The impact sent debris into the stratosphere which rained down all over the planet. The energy contained in the debris made the atmosphere turn into an oven, killing almost anything that was out in the open and setting fire to the world's forests. It also caused acid rain which killed off surviving plant life and anything in the surface of the ocean. The soot from the fires blocked out the sunlight for some years so survivors had to glean meat from the fallen corpses of the dinosaurs. While it wiped out most of the life on Earth, it gave a chance for some small burrowing mammals to fill the vacant niches left by the dinosaurs.
Zigs, how do you know these things? I am constantly amazed at the depth, breadth and topics that members here exhibit. It seems I'm hanging out with a brilliant bunch of people!
I've loved geology ever since I found my Dad reading an Encyclopedia when I was about 6 We've identified another place (more local) that might have the same impact layer, the cliff at the abandoned hoverport a few miles from us... We have plans to investigate it
Thanks for the photos and info @Zigs! It's so much more fun when people do a show-and-tell than to listen to lectures. Amazing that the events show so clearly in your cliffs. I never went to Dorset and now I'm regretting it.
I like a good show and tell Dorset has got some good bits but Tetters is scared of the place Couldn't find a better pic but the layer of pebbles here is probably the great storm of 1824.
We investigated further today.... ...And found it The KT Boundary. The same layer of shattered flint, but this time topped by a darker layer which was either burned by the global fires or cooked by the ejecta falling back to Earth at a temperature of several hundred degrees Celsius Anything caught outside on that day would have burned to death
Scary, isn't it. Do you find any fossils in that layer of flint? We've picked some nice sea urchin fossils on the beaches in Denmark. And mussel fossils too. They are all over the place so nobody bothers to pick them bar tourists.
Couldn't have got any scarier Not seen any fossils yet but if there are they'll be shattered and blackened We find sea urchin fossils here too, got a few in the garden. The chalk layer had been lifted up and eroded before the asteroid struck, hence all the flint lying on top of it, it had been weathered out of the chalk. We have the same here in the garden. I cleaned up some of the debris after scraping off the mud stuck to them to have a better look at. Flint has a hardness of 7 (steel is 6.5, diamond is 10) so it must have been a hell of a blast to shatter it from 8,000 kilometers away.
That's great @Zigs I've always been interested in it. I've always thought that all the stones in the soil is from the glaciers when they were moving over the soil, some are big.
Ta Logan The glaciers did move a hell of a lot of stones by picking them up and dumping them miles away but that was quite recently, 10 thousand years ago. This Asteroid hit the Earth 65 million years ago, that's how the debris got buried under lots of other stuff since
