The river holds a lot of history.
Some of it has flowed downstream with the currents and moved on to the sea but some of its oldest history is still here. And when the water is low you can find one of the most striking features visible along the Ottawa River shoreline: The stromatolites on the Quebec side of the river. They have been scraped down by glaciers and eroded by time but the ancient stromatolite bed remnants are still remarkably beautiful and visible.
These stromatolites are over 450 million years old and were formed during the Paleozoic period when this area was located near the equator and was covered in a warm shallow sea. The stromatolites are built up in layers by cyanobacteria, also known as blue-green algae, and are accretionary structures rather than body fossils.
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All images © Karen McRae, 2012