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John O. O'Brien has worked out a problem with his book,
Oak Island Unearthed. Now:

Historically Beavering Through Those Dammed Oak Islands

Prepared by Jack Sorenson
for a March 2018 meeting of the Lunenburg County Unity Group

My parents were both geologists. My mother was the first female graduate in geology at the University of Idaho. My father, after getting his geology degree at the University of Minnesota, had gone to Idaho to get a degree in mining engineering, and had taught some of the classes to my mother-to-be.

I grew up in Wallace, in Idaho's "panhandle," about 200 kilometres (125 miles) down from the B.C. border. My town is in the Bitterroot Range of the Rocky Mountains. It is the County Seat of Shoshone County (think Shoshone Indians), and is the centre of a major hard-rock mining area, known as The Silver Valley, which has produced tremendous amounts of silver, lead, and zinc. All of that was very important in the World War II effort while I was a little kid. My Dad was a geologist/engineer for a major mining company, and as I was growing up I went down into several mines and worked one summer in the mill associated with a concentration plant. After I graduated from high school, my Dad, who by then was Vice President of his company, took me to see the shaft that served a working mine his company had recently bought. We went into the building housing the shaft cable, and he suggested I look down the shaft, as far as I could. I saw lights going down, down, down. And he told me to not expect to see the bottom, as it was 6,000-feet deep! A year ago, that shaft was over 9,600-feet deep (1.82 miles/2.93 kilometres). An important point: mining shafts are needed in the search for mineral seams that can be mined more-or-less laterally. I write of this so that you will accept that I know that shafts which are not water-wells, are for mining rather than for hiding treasure.

After my first year of teaching in the music department at Dalhousie University, my mother and I went to Europe for six weeks. We got back on June 20, 1971, and then - on the first day of spring - we drove down to see Oak Island. As we stood beside the somewhat-ravaged "money pit," my mother said: "I wonder what the dickens they were mining..." Now you know where I am coming from.

Without the dams, it would be very apparent that there are two islands, and that they are on two different bedrocks:

West = Halifax Formation
East = Windsor Formation

When those two strata collided millions of years ago, the Windsor Formation drove under the Halifax. The softer bedrock of that East island, not being covered by the hard rock of the West island, eventually eroded to a much lower point. That erosion, over a vast amount of time, produced the condition that we see today:

West = Halifax Formation
Glacial till overburden, now:
from 15 to 30 feet (4.5 to 9.2 meters)



East = Windsor Formation
Glacial till overburden, now:
Approximately 172 feet (52.5 meters)

Try to imagine the major melt of a big ice age. Huge amounts of earlier earth formations were being pushed from higher areas toward the seas. And much of the red-clay-dominant ground moving into our area, was carrying - at its lower levels - less thick layers of lighter-colour clays, such as grayish (some of which was palygorskite), white, yellowish, and grey-green.

Now, consider that those more-fluid and less plant-fibrous lower-level clays, when suddenly dropping down from the much higher edge of the Halifax formation toward the more eroded bedrock of the Windsor formation, could result in a very thick accumulation. Indeed, the three layers of grey clay that are directly above the bedrock of the East island, total approximately 44 feet (13.4 meters). That astonishing volume is covered by as much as about 108 feet (30.5 meters) of other overburden.

The above information is meant to trigger interest in a truly significant published book (now in its third edition) entitled Oak Island Unearthed. The author, John O. O'Brien, is an elderly former hard-rock miner who worked underground in various regions for 36 years. He now lives in Bridgewater, about ten blocks from my and my wife's North Street Apartment.

A couple of years ago, when I first encountered an earlier edition of his book (published in 2014), I got in touch with O'Brien so that my mining-town background could exchange with his. After a quick discussion I suggested that he needed a web-site. With his permission I started to pursue the project. My first effort was to introduce him to two other "treasure shafts" in Mahone Bay, about which he had no knowledge; and then to write a primary article, Mahone Bay Unearthed, for the new web-site.

Mahone Bay Unearthed led to the publisher including significant parts of that article in the recently-published third edition of O'Brien's Oak Island Unearthed. As well, I was asked to write the forward for that new edition.

Recently, John O'Brien prepared a short new article,
meant as an addition to the new Third Edition of his book.
It presents several points, including the following:

1. Operations began about 1200 years ago (around 800 AD), as established by the carbon-dating of coconut fibre.

2. Those people who first came up here with coconut fibre, were Mayans — probably merchants with slaves — who sailed and rowed up the coast with the aid of the Gulf Stream. They would have been scouring our coast-lines when the sea levels were perhaps about 15 feet lower than today.

3. In red-clay-dominated Mahone Bay, after discovering significant low-down layers of light-coloured clay in at least three regions — Mader's Cove, Martin's River, and East Oak Island — they dug shafts and began mining a substance which was valuable to their Gulf of Mexico culture.

4. Probably when they became fully aware of the astonishingly-thick low-down layers of grey clay at East Oak Island, they refilled their shafts at Mader's Cove and Martin's River, so as to "cap off" access to The Underworld. Then they gave all their attention to the truly "big find of grey clay" about which we are now aware.

5. In coming up here, they also were trading with the Mi'kmaq, whose word, "Sakawachkik," means "ancient traders from the south." They came up in the spring and left in the fall. Significant is the fact that the hats worn by the Mi'kmaq and the Mayas, were near-identical.

6. Very likely, on each trip up here and back down south, the merchant crews passed and viewed the stunning ocean-washed-out caves on Feltzen South peninsula, which we now call "The Ovens." Embedded in their minds would have been the few similar caves which were constantly visible to them across the open-flowing and cavern-eroding channel washing between the east island that they were mining, and the somewhat larger west island. Around 1521-22, the tide level would have been about seven feet lower, and the small washed-out caverns would have been more visible than after the subterfuge of damming.

7. Around 1520 to 1522 the Aztec armada that was escaping the clutches of Cortez, came to Oak Island to bury their king, Montezuma II, along with treasures from their rapidly-deteriorating civilization. Because of their several centuries of clay-mining in Mahone Bay, they knew of some geologically-special "Ovens"-like caverns which they could use for that purpose, and which could be hidden by the building of two dams. As the icing on the cake, nearby was their old and very productive clay mine, which they could turn into a remarkably clever and effective decoy and booby-trap.

In the the early autumn of 2017, O'Brien awoke in the middle of the night, as a long-repressed memory hit him like a ton of bricks. It had been buried deeply enough that it couldn't pop out until he had gotten all the other stuff out of the way while working through three editions.

That memory:

In the summer of 1958, 13-year-old John O'Brien was on East Oak Island with his father. They were sitting on the western side, looking across toward the left side of West Oak Island. Whether or not his father and a couple of his father's academic friends had actually seen evidence of Ovens-like caverns over there, their awareness of its geology would have suggested as much.

What was obscuring the view? It was the filling-in associated with the two dam-like dykes which had been built to connect the islands at their north and south coasts. O'Brien has confirmed by compass-readings that the east-facing coast-lines at both The Ovens and West Oak Island, have received the same heavily-washing waves. And the geology of both is of the hard-rock Halifax Formation, showing simple folds (anticline/syncline). But while the coast-line at The Ovens shows significantly large caves on the left side of the eastern face, along to the right are smaller ones. It is those that are duplicated in the fewer smaller caves at West Oak Island.

It is the above information that O'Brien had buried all-too-deeply in his miner's brain. He made me aware of the issue when he called last fall, asking me to accompany him on a trip to have a new look at The Ovens. So it is only relatively lately that I have known of the big picture.

While working on the third edition of Oak Island Unearthed, O'Brien's locked-up brain had been puzzling about how the Aztecs had managed to mine burial chambers in the West Island. After the new edition had been printed, he decided that he had to write an article that would answer a major question: because those people did not have iron and steel tools, how long would it have taken them to mine such tunnels in such hard rock? He found himself conjecturing that it might have taken as many as twenty clay-mining seasons to have achieved it. And therefore he would have to expand and elaborate an article that we published on the website about a year and a half ago, entitled The Power of Prophecy to the Aztecs. Fortunate it is, that the mining-tool issue could disappear with his middle-of-the-night memory-flash. Although in the very few surviving Maya/Aztec documents there are statements that could be used in such an argument, he would have been setting up a huge mountain of controversy that could trash the validity of his already-published writings.

How lucky it was that, a few months ago, "The Ovens" burst to the surface of O'Brien's brain. Although it will require yet another modification of his book, it does seem to be the last, and critical, piece of the Oak Island puzzle.

The illustrations below, are taken from pages 17 and 188 of The Last Billion Years: a Geological History of the Maritime Provinces of Canada, published in 2001 by Nimbus.

1: "Layer cake" strata = essentially the "Windsor Formation" of the EAST Oak Island, with its several-hundred-year-old Mayan/Aztec grey-clay mine, which was turned into a booby-trap by the Aztecs around 1521-22 A.D.

2: "Simple folds" = essentially the "Halifax Formation" of the WEST Oak Island, with its one or two natural chambers used by the Aztecs for the around-1521-22 burial of Montezuma II and his treasure.

3: Raised beaches from about 15,000 years ago are still to be seen in a few places on the Nova Scotia south shore.

geological graphics maritimes
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