I have always asked myself..."why would someone dig down 90-150 ft to bury a treasure?"
This seems impractical knowing you would have to do it again to retrieve the treasure.
I do believe the the logs every 10 were put in place to reduce the indentation that would form over time as the earth below settled. But that doesn't mean it was too hide treasure...possibly salt mining activity since islands are known to form on salt domes which nova Scotia is known for.
Since the three guys who found the impression in 1795 sought funding to continue the dig in 1804 as the Onslow company, they were convinced there was treasure. But that doesn't mean there was treasure.
So I believe, as with most legends there is some truth to it, but in this case there is no treasure.
So a very precise and regular backfilling scheme involving recognizable empiric details found in other stories then?
There was an open air commercial fishing/salting(?) operation at OI in 1753-58 in the pre English colonial period. It was on the mudflat at Smith's Cove. There are well known salt cavern deposits in NS, but OI is not one of them. They were not mined in the 18th century even where they exist.
If a deep hole was ever dug in early colonial times (and they were) we would need to list the reasons why that was ever done to understand what is most likely. I don't even think the list goes far beyond digging a well.
Since we know the oldest stories aren't factual in even their main details we know they have suffered embellishment and alterations from some base reality which we can strive to know from reliable evidence. There is no corroborating evidence for any searches at OI prior to 1830. That includes 2 printed works that do mention other lesser known folk stories from nearby.
OI needed a backstory. It would have never served to allege you were looking for something that wasn't already pre charged with a ton of intrigue. Most of the primitive stories we still peddle that concern our origins on this planet are pure fictions, and they are not helped by labelling them, or including them, in legends.
What is the recognizable legend at OI if not that of Enoch's shaft and vault that first floods and then collapses into the abyss when the 3 searchers approach the vault? Should we conclude the legend is based on real events when we thoroughly understand this was always given as just allegory to make a point about how the most basic questions about life and death are unanswerable? What does it mean when old allegory allegedly reappears as a real details in NS in a alleged factual search? It is life imitating art that is already imbued with mystery. There is a fundamental reason why this story resonates and was kept alive by Freemasons. It is not because there was ever something in a hole in NS that would answer questions that are unanswerable.
What is buried a OI is an unanswerable question that is perfectly well adorned with Enoch's old legend. It is a modern attempt to use reason to account for a fiction, and it must fail. In failing it is meant to push you more strongly in the direction of having faith. Faith alone can move mountains and perforate an island to no end. There is even government money for faith based initiatives, and there is capitalist money for making a spectacle of it. Real need for questions and answers, not so much....