K/T boundary layer. This geological boundary is a thin layer of clay (dark) containing iridium,separating older Cretaceous (K) and younger Tertiary (T) rocks (white and red sandstone). The boundary layer is only a few centimetres thick,but is found worldwide. It is thought to have been formed from material ejected by the impact of a large asteroid around 65 million years ago. This is thought to have triggered the extinction of the dinosaurs,along with many other forms of life. Photographed in the Bottaccione Gorge,near Gubbio,Italy | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Bond, Martin |
Bildgröße: | 4672 px × 3827 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
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