Earth Science in the Horseshoe Valley, November 8th, 2025. Submitted by Tom Koleszar

Nineteen MalaNats members toured the Horseshoe Valley area looking at variety of glaciological and geological sites. And the weather even cooperated – for November: no sun, but no wind or rain either!

Glacial Sediments at 12 Mile on the Goat Main. B. Kurtar

Our first stop at 12 Mile on the Goat Main was mostly about recent (10,000 – 30,000 years ago) ice advances and retreats at the close of the last ice age. Some of the sediments left behind as the last ice left the area are nicely exposed in the gravel pit at 12 Mile.

 

 

 

 

On the Beaver Main we stopped at a view point overlooking Dodd Lake and towards the Rainbow Range.  Here we talked a little more about the geographical features left behind by the ice, and also delved into the regional geology and geological history of the area. (And enjoyed the nice view!)

Looking over Dodd Lake to the Rainbow Range. B. Kurtar
Looking at Rocks near Beaver Lake: B. Kurtar

A little further down the road we stopped to hear about fractures and intrusions, and saw swarms of hydrothermal dykes of varying colours. We found the rotten rock that hydrothermal fluids create (and that geologists love to find!) and learned a bit about mineralisation in these veins.

 

 

 

We then drove further up the road to Little Horseshoe campsite where we enjoyed our lunches and warmed up around a nice campfire.  Wide ranging naturalist discussions ensued, going all the way from rocks to mushrooms!

Lunch and a Fire at the Little Horseshoe Lake Campsite. B. Kurtar

On the way out, we made one last stop, walking up an old road to a rock pit where a nicely mineralised quartz vein is exposed. Here we did a bit of hunting for pyrite, chalcopyrite, molybdenite, and other sulphide minerals within the quartz. As usual, no one found any gold! From there we headed back home having enjoyed a nice day, learned a little bit, and perhaps acquired a few little treasures!

Dykes and Intrusions Exposed in the Road Cut: B. Kurtar
Quartz Vein Exposed in a Roadside Pit. B. Kurtar