Applying GIS to solve a 200 year mystery

Unearthing the Island's Secrets: The Intersection of Ancient and Modern Mapping Techniques

Oak Island is an infamous island on the south shore of the Province of Nova Scotia. It is at the center of centuries-old lore that includes the Free Masons, Knights Templar, and pirate booty. The island is believed by some to hold one of the greatest treasures of all time, intriguing treasure hunters for more than 200 years. No one has found the treasure yet, and some have even died trying.

Enter Rick and Marty Lagina, brothers from Michigan who bought the rights to much of the island to try to solve the mystery. They use modern technology and input from theorists and independent researchers to look for the treasure.

The History Channel’s The Curse of Oak Island chronicles the brothers’ treasure hunting expeditions with a team of archeologists, field surveyors, treasure hunters, and more. In its 8th season, the show has grown in popularity, attracting nearly 3.5 million viewers per episode.

The Theory

Using tangible features to piece together the treasure map

As a big fan of the show, Erin was surprised by its lack of a GIS Analyst. She grabbed LiDAR data from Nova Scotia’s GeoNOVA site, available aerial imagery, information from the show, and historic survey maps from previous investigations to try to identify patterns and relationships between features.

The positioning of boulders across the island has intrigued investigators for centuries. The “Nolan’s Cross” boulders across the properties of late Fred Nolan are a popular example of how previous searchers have attempted to make sense of the boulder patterns across the island. Erin sought to further answer what the relationships were between the boulders and the treasure lore. What were their purpose? Could Erin help piece together the island’s tangible features to better explain what happened there?

Erin’s work went back to the basics of mapping and measuring—the square and compass. She asserted that these items were not originally meant to be symbolic, but practical mapping and drafting tools. When these tools’ principles are applied to the island, the positioning of the boulders start to make sense. The boulders appear to be marking triangulations—arc intersections—and Erin suspects they can be used to recreate the island’s original surface master plan. These newly discovered spatial relationships combined with clues from Zena Halpern’s previous research could pinpoint the vault’s true location.

The Technology and Analyses

Enhancing LiDAR with local relief modelling

Erin used local relief modeling to enhance the island’s ground surface by purging the data of natural undulations (e.g., big hills and valleys). This process enabled her to focus on human scale features like large boulders, areas used for agriculture, roads, pits, spoil piles, etc. The derived local relief model provides a unique opportunity to identify hidden features and patterns across the island. To learn more about local relief modelling, check out this paper by Ralf Hesse.

Artifact Analysis

Erin suggested that “The Anchors” from the Oak Island map presented by Zena Halpern are not depicting nautical anchors, but what would be considered in modern day “Ground Control Points” or “Survey Markers”. Erin proposed that these two boulders would have been the starting points for deriving all other deliberate boulder positions across the island—including Nolan’s Cross.