Calcite (Inventory)/Rimstone Dam

From LagWiki

The Rimstone Dam field of the Calcite section should be used to record any observation of rimstone dams.

Rimstone dams are calcite deposits that form at the edges of water to make terraces or walls over which the water spills. Unlike shelfstone, they are not flat and horizontal, but are sloped and have height. Each terrace is stair-stepped from its neighbor. They form at the edges of pools or along sloping water paths when the water spills and loses some of its CO₂.

Rimstone dams can occur singularly or in large, cascading terraces of dams. The spaces behind each dam will usually be lined with pool spar. They can vary greatly in both height and width from small ripples to large walls. Smaller rimstone dams are also known as gours.

Look for them on the floor where water may have once flowed and take care during survey not to damage them as the walls can be very thin and fragile.

Gallery

A large group of rimstone dams	Gours or small rimstone dams
Rimstone dam. Other items visible include: shelfstone, popcorn, and a crust over floor sediments.

See also

• Shelfstone
• Pool spar

References

• Hill, Carol; Paolo Forti (1997) Cave Minerals of the World (Second Edition ed.) National Speleological Society pp 92-94 ISBN: 1-879961-07-5
• Palmer, Arthur N. (2007) Cave Geology CAVE BOOKS, Dayton, OH pp 277-278 ISBN-13: 978-0-939748-66-2, ISBN-10: 0-939748-66-5

Calcite (Inventory)/Rimstone Dam is a part of the cave inventory project.