I’ve been talking lately about the way that sand ripple formations may have contributed to the patterns in the White Strand Formation rocks on Garretstown Strand. It has reminded me of another location where you can see sand ripples preserved in the stone. Last year I visited Cape Enrage in New Brunswick which is on the coast of the Bay of Fundy in Canada. At Cape Enrage the strata are so steeply dipping that they are almost vertical and form high cliffs. The rock strata are sandstones belonging to the Ward Point Member of the Cumberland Group – and like the Garretstown rocks are from the Carboniferous Period.
Along the near-vertical faces of the bedding planes you can see sand ripple patterns of various types preserved in the rock. Some of the ripples are weathered and flaking to show the many layers that go into their make-up. On the shore below the cliffs are occasional boulders with un-eroded ripple surfaces. There are also blocks of stone showing cross-sections through the rippled sand formations that reveal the complex cross-lamination of the sediments as they were deposited by one of a series of braided rivers flowing to the sea, where the channels migrated across a broad valley floor.
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Amazing. Never seen anything like that. Particularly like No. 4.
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Yes, really weird to see broken sheets of sand rippled stone arranged almost vertically at the top of a cliff face 145 feet high. (These ripples are, I have just discovered) actually be from braided river beds, maybe estuarine, rather than seashores). Just imagine the earth forces that were involved in re-arranging the rocks from horizontal to that position!
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Its strange that such forces, as you say, preserved such delicate forms.
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A lot of it would be random chance, as in fossilisation. A marvel that things survive.
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Absolutely, for every section of ripples preserved in this way, countless millions have disappeared as normal, like fossils as you say. Nothing mystical, but even more of a marvel.
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