• Speleothems in Miller's Chapel.

    Oregon Caves

    National Monument Oregon

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  • Haunted Candlelight Tours

    Haunted Candlelight Tours Offered Sunday, October 26 through Friday, October 31, 2014. The tour begins at 4pm and are first come first serve. The tour is limited to 12 people per group. Last regular cave tour will be at 3pm.

Speleothems

Speleothems, known as drapery at Paradise Lost in Oregon Caves.

Speleothems, known as drapery at Paradise Lost in Oregon Caves.

NPS

Speleothems are depositional features in the cave. They are also known as formations or cave deposits. They do not occur in caves until a cave has an opening to the outside world. Openings allow for the deposition of calcite.

Two processes create speleothems: evaporation and loss of carbon dioxide. The first process, evaporation, occurs when dry outside air enters the cave, evaporating the water and leaving behind the minerals. This process is not common except near entrances and it creates the formation known as cave popcorn. The second process occurs when water entering the cave loses carbon dioxide. When water from the soil enters rock, it is under more pressure. When it reaches the inside of the cave, the pressure reduces and the carbon dioxide can escape. This reduces the acidity of the water, causing water to be supersaturated in calcite, which settles out of the water. This is the slower of the two processes, but is dominant throughout most of the cave.

Did You Know?

The vista from Mount Elijah looks to the Red Buttes wilderness, Mount Shasta and other scenic vistas.

One of the most spectacular vistas near Oregon Caves is located on Mount Elijah. The hike is strenuous if you start at the monument but the staff at the Visitor Center can direct you to another, less strenuous trail to the mountain.