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| Trail Map |
The natural rock arch on the Burnt Head Trail was formed after the Pleistocene glaciers melted, between 10,000 and 8,000 years ago. The sea level gradually rose by about 120 metres as huge ice sheets and glaciers across the northern hemisphere melted.
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| The arch on the Burnt Head Trail is made of rock of the Drook Formation. Photo courtesy of Chris Woodworth-Lynas. |
On the shores of Conception Bay, rising water levels and waves from strong northeasterly storms battered the coastal rocks. Over time, the constant assault began to erode the shoreline, where some rock had already been loosened by the glaciers' retreat. Eventually all this action washed away pieces of bedrock at sea level. In some places, unstable overhangs were left as rock was removed. These, too, eventually collapsed and were washed away by the sea. This is what occurred to form the arch you see today.
When you look closely at the arch, you can make out both the rock layers, which have been folded downwards, and straight partings, or cleavege, tilted to the right. Cleavage is the result of great pressure causing re-alignment of clay minerals. Rocks with good cleavage can be split easily, yielding rock pieces that are ideal for building house foundations or root cellar walls.
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| Features of the Drook Formation: The orange lines show the folded sedimentary layers (which were originally flat). The black dashes represent clay minerals in the sediment, which have been realigned through compression (red arrows) to form cleavage. Drawing courtesy of Chris Woodworth-Lynas. |
The sheltered cove in the area below and inside the arch is deceptively large. A17-foot open boat can fit inside — with turning space — at low tide. The craggy ledges of the arch are perfect places for nesting birds. Ravens have made their nests on rock walls of the arch, keeping their young safe from predators. The croaks of raven parents and nestlings can be heard during the nesting season in spring to early summer.
Information provided by Chris Woodworth-Lynas.