Bassett Island Isthmus EarthCache

Power Island and Bassett Island are two islands located in the West Arm of the Grand Traverse Bay. Power Island is roughly 200 acres, which includes 3 miles of shoreline and over 5 miles of trails. Bassett Island is significantly smaller, only a single acre, but home to four rustic campsites. Power Island and Bassett Island are connected by an isthmus.

An isthmus is a strip of land that connects two larger land masses. Panama, which connects North and South America, is probably the most famous example of an isthmus. Isthmuses can be formed by any of a number of geological processes, such as weathering, erosion, volcanism, and plate tectonics. Isthmuses can also be man-made, formed by floodings and the construction of land bridges and dams.

Isthmus - a strip of land with water on both sides

A tombolo is a special type of isthmus, which is formed by deposits of sand, gravel, or silt. They are formed by beach sediments being swept and accumulated via wave refraction and lateral long shore drift. This sediment transport leads to the formation of a spit or shoal, which then connects the island to the mainland. Once a tombolo has formed, the island is no longer an independent land mass, but is considered a tied island.

Tombolo - island attached by a bar or spit

1. Approximately how wide is the isthmus?
2. Do you think that this isthmus is also a tombolo? Provide at least two observations to support your decision.
3. (Optional) A photo of yourself anywhere along the isthmus.

Failure to e-mail information within 48 hours of logging your "Found it" will result in your log being deleted