Category Archives: Manitoba

Steep Rock Quarry 2022

 

After photographing the ice of the lake and then the crocuses o the cliffs, we moved to the quarry nearby from which limestone was mined from 1913 to 1992. I had not stopped to look at it last time I was here about 15 years ago, but it was well worth a visit. The quarry is now filled with sensational turquoise water. At least the water appear

What makes Steep Rock special is limestone. Limestone is a sedimentary rock made up of different shaped crystals of calcium carbonate (CaCO3) called aragonite and calcite. The limestone was formed by the accumulation over millions of years of small pieces of exoskeleton left behind by marine  invertebrates  including corals, gastropods (snails) and clam-like brachiopods. These pieces were compressed by the weight of the ocean above them and by their own weight. Eventually these pieces were solidified into rock that was exposed when the sea retreated. After the sea dried up and the last glacier scraped off the top layer sediment that had accumulated the limestone was what was left. Over thousands of years the cliff has suffered erosion. The caves add to the intrigue of the place.

This area was a sea for about 350 million years. Each layer of rock was separated by other rocks such as shale and dolomite. Each layer represents a different period in the history of the area. Limestone is a soft rock that often breaks up into small pieces of rock that can be excellent for gravel. In water it often makes the water look turquoise.

We also noticed a large number of Red-side garter snakes. There were not as many as the last time I visited the area when we actually heard the snakes rustling in the grass before we saw them. That was a bit disconcerting, even though the snakes are not dangerous.