Looking out on a tranquil scene like this, the photo taken at dawn on a mid-December day, we tend to forget that the flat surface of the sea hides a mountain landscape: the underwater terrain beneath this view of the north end of the Sound of Mull drops to depths of over 60m and rises again so it breaks the surface.The areas of shallow water are often formed by harder rock which, when sea level was lower, were left sticking up by the processes of erosion. The coast which runs from Kilchoan westwards to the end of Ormsaigbeg illustrates this well. Anyone walking along it will have noticed that the rocks form ridges parallel to the shore, most of which are igneous dykes, part of the cone sheets associated with the great Ardnamurchan volcano.
Unfortunately, one of these sheets rises near the surface in the middle of the entrance to Kilchoan Bay. This reef, which is visible from mid-tide, isn't at all clearly marked on the 1:150,000 marine chart, but members of the village, one of whom is Alasdair MacColl, have erected a steel pole with a radar reflector on top to warn ships and boats of the danger. In the time we have been here, this has been hit at least twice, probably by fishing boats, the first time nearly knocking it over.
Unfortunately, one of these sheets rises near the surface in the middle of the entrance to Kilchoan Bay. This reef, which is visible from mid-tide, isn't at all clearly marked on the 1:150,000 marine chart, but members of the village, one of whom is Alasdair MacColl, have erected a steel pole with a radar reflector on top to warn ships and boats of the danger. In the time we have been here, this has been hit at least twice, probably by fishing boats, the first time nearly knocking it over.
Similar underwater 'mountains' rise in the middle of the entrance to Loch Sunart, reaching the surface to form a group of small islets and shoals, the New and Red Rocks: two of the small islands are just visible in the above photo. One of the New Rocks is marked by a light buoy which flashes green every 6 seconds.The miserable southeaster continues to blow. With a westerly gale forecast for tonight, we were down in the bay this morning checking the lashings on the kayaks. The shore is thick with kelp torn from its roots. The only creatures who seem to enjoy this weather are the gulls.
The deteriorating weather has cause the Tobermory schoolchildren to be brought home early. CalMac rang the school to say that a special boat was being provided to bring them across at midday, and that it would be the last sailing of the day.
I am indebted to Alasdair MacColl of Portuairk for the following information. The 'steel pole' to which I referred is properly called an 'isolated danger mark', and the two black balls on top indicate that shipping may safely pass on either side.
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