SHELFSTONE
Shelfstones are planar- to subplanar-topped projections of speleothem formed at & just below the waterline of cave pools. They are almost always composed of travertine. Shelfstone only forms if the water level in a cave pool is stationary for long intervals of time, or varies only slightly through time.
All shelfstones shown below are composed of travertine.
Green Lake - cave pool with standing water. Shelfstone is not well developed along the pool margins. Green Lake Room, King’s Palace Trail, Carlsbad Caverns.
Dry cave pool with moderately developed shelfstone along the foreground margin. The shelfstone formed when the pool was full of standing water. Northwestern portion of the Big Room, Carlsbad Caverns.
Shelfstone rimming dry cave pool, near Breast of Venus, Big Room, Carlsbad Caverns.
Shelfstone rimming dry cave pool, near Breast of Venus, Big Room, Carlsbad Caverns.
Shelfstone rimming dry cave pool, near Breast of Venus, Big Room, Carlsbad Caverns.
Shelfstone rimming partially drained cave pool. This pool still has standing water (dark green area at bottom), but the shelfstone formed when the pool was full. Near Breast of Venus, Big Room, Carlsbad Caverns.
Shelfstone rimming dry cave pool, near Top of the Cross, Big Room, Carlsbad Caverns.