Northwest Dive Club

This is not far from the hamlet of Woss, although the "roads" are terrible and its over an hour of crawling to get in there from highway 19. And many truck scratches... There's about 900-1,000ft of cave before getting into trimix depths. Max depth is 132ft, total there is about 1900ft of cave here. Sadly it ends at a very narrow slot. It could be done on the way too or from the Wet Dream system - if you were motivated to haul stuff in the 350m trail and had leftover tanks.

https://vimeo.com/346766620

Fascinating. And cool as heck...

What can you tell us about the geology of the cave and its possible formation?

Vancouver island limestone/marble is all basically in the same chunk. It was laid down in the arctic many millions of years ago (much older than FL or Mx limestone) back when Pangea was the lone continent on the planet. The tectonic plates broke apart and drifted around, that particular plate drifted out into what we now call the Pacific. Eventually it drifted back and crashed into the North American plate which lifted and folded the limestone as well as highly metamorphosing it into marble. Various igneous intrusions happened at this time, some of which are in the video. These new mountains almost immediately started eroding. The fractures in the marble allowed flowing water (creeks/rivers) to erode almost all (2000+) island caves. Most island caves remain active streamways. There are a some which are perched relics ie vadose caves. This is a good visual of the process. https://www.bgs.ac.uk/mendips/caveskarst/caveform.htm