Midnight Dome EarthCache

Midnight Dome

_{© Brad Hubley, 2025}

The Midnight Dome is a knob of rock, common to the area south of the Tintina Trench fault line. The geology of the two edges of the Trench differs greatly due to a slippage of 450 km that occurred within the last 65 million years and corresponds with recessive weathering of rocks.  The Tintina Trench, in the Dawson City area, marks the edge of the glaciers as they existed 3 million years ago. Generally speaking, gold laden placer gravels occur south of the Trench and hardrock deposits are found on the north side. 

Bear Glacier

_{© Brad Hubley, 2025}

Glaciers, such as the Bear Glacier (seen here in Bear Glacier Park in British Columbia), are large, slow-moving masses of ice that form on land when snow accumulates and compacts over many years. They are a crucial part of the Earth's climate system and play a vital role in regulating water resources. This glaciation may have changed the direction of the Yukon River from south flowing to north. The river cut a path through the bedrock instead of making a path in the lower, but ice-filled, Tintina Trench. Later glaciations may have changed the direction of the Yukon River again.

Logging Requirements:

To log this Earthcache, send me the answers to the following questions (please do not include them in your log).

1. The Midnight Dome is a type of what kind of rock?
2. What is recessive weathering?
3. What are placer gravels?
4. What kind of hardrock deposits are found on the north side of the Tintina Trench?
5. In what direction is the Yukon River currently flowing?
6. Optional: an image of the area is greatly appreciated but not necessary.