The Big Rock at Beaver Island
Although the land that makes up Beaver Island first appeared 11,000 years ago, there have been a lot of changes over time.
When the lake dropped to a very low level from 8,000 years ago, the island was actually a peninsula and was part of the mainland. Next, 4,000 years ago glacial melt caused the lake to rise and submerge nearly the entire island under Lake Michigan. It was this melt that dropped The Big Rock here. It originated in the Canadian Shield in modern day Ontario. Glacial boulders, like The Big Rock, are unlike the bedrock beneath them and are known as “Erratics”.
Next, glacial refreezing caused the water levels to drop again, creating a slightly smaller island than present day. The present shoreline was caused by isostatic rebound, when the land masses that were depressed by the weight of ice sheets rose after the removal of the huge weight of the ice.
To Claim the Find:
A) Take a picture of you or your GPS and the Big Rock at the above coordinates and post it with your log.
B) Answer these questions by e-mail or Geocaching messages
1. Who's tooth filling did the locals say this rock belonged to?
2. What type of rock do you think The Big Rock is? Give us your best guess.
Virtual Rewards 3.0 - 2022-2023
This Virtual Cache is part of a limited release of Virtuals created between March 1, 2022 and March 1, 2023. Only 4,000 cache owners were given the opportunity to hide a Virtual Cache. Learn more about Virtual Rewards 3.0 on the Geocaching Blog.