About two weeks back I had to make a trip down to Kenton-on-Sea in the Eastern Cape. Now we have been going to Kenton since I was just a nipper as I have an uncle who has lived there since time immemorial. He is nearly as old as the rocks that outcrop along the shoreline, or so it seems to me. Anyway, I mustn't digress. That portion of the coast is not only beautiful but full of interesting geology - two rivers stretch inland for many miles, with Kenton almost marooned between the two - it was in its day almost an island before they built the two bridges across the Bushman's River on the western side. Vertical sediments of the Cape Fold Belt outcrop along the Kariega River, fossilised sand dunes stand sentinel along the coats, one of which forms one of Kenton's famouse landmarks, Carriage Rock, because it looks like an old carriage.
But it is the modern sand dunes that I want to talk about today. They stretch for miles along that Eastern Cape coast, unsullied by developments or human activity. At Woody Cape, on the northeastern corner of the Addo Elephant Park there is a huge dunefield called the Alexandria Dune Sea which forms part of a larger dune system the details of which are not to be discussed here.
What I did want to illustrate was how these dunes migrated ahead of the prevailing winds and I took a short video which shows the aeolian (wind blown) sands being driven up the windard (stoss side) of the dune and jetted into open space, where they settle as foresets on the lee side. Ongoing wind action will cause the dunes to migrate downwind over time, enveloping all that stands in their way.
Check out the video below.
https://www.facebook.com/gerald.davie/videos/10216405998769064/
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