A pair of images depicting coastal erosion of a coastal promontory off the coast of Kythira,Greece. The top simulated image shows how the arch keystone might have appeared before its collapse. The bottom image shows the same feature as it appears in the present day (unmanipulated). A sea arch is a natural opening eroded out of a cliff face by marine processes and may take many hundreds of years to form. Arches are therefore ephemeral geological landforms. They develop where waves attack a plane of weakness which cross-cuts a promontory. Caves produced on either side of a promontory might be joined over time to become a tunnel and,finally,an arch. Ultimately the keystone itself will erode leaving only a seastack. The architecture of an arch and the speed of its erosion is a reflection of its lithology and structure | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Parker, David |
Bildgröße: | 5501 px × 6345 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |