Ordovician worm castings from Bell IslandThis past summer 4 of us did a 26 km circumnavigation of Bell Island. Bell Island is composed of Ordovician sandstones and siltstones with beds of hematite (iron ore). The beds dip gently in a westerly direction indicating there hasn't been much tectonic activity since the beds were laid down. The Ordovician is a geologic period spanning the time 488 to 443 million years ago.
After our rounding and answering the call of nature, I had a look in the talus slope of the hill behind the beach. I knew what I was looking for and after a few minutes I found it, a rock with pronounced worm castings. Worm castings are the remains of worm tracks through the sediments.
Most people would know about the fossils left by trilobites; they left their hard exoskeletons as they moulted. Worms are pretty delicate so they don't leave a lot of fossil evidence. The rocks of Bell Island don't contain fossils of the worms but they do preserve the ghostly trails of their existence.
Rocks are part of the paddling environment and I find it interesting to know a little about them.
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