Bulbous Stalactites: An Unexplained Formation
Some researchers believe that turnip-shaped bulbous stalactites may be only a variation of a welt or shield. It has been observed that caves with bulbous stalactites tend to also have shields and welts, so there may be a connection. Another theory for the origin of bulbous stalactites has to do with intermittent flow of water. Often, a growing soda straw stalactite can have water flowing both internally and externally. If the internal flow stops, calcite may plug the internal channel. Then if the internal flow resumes, the blockage may cause the stalactite to rupture. If the water oozes out in small quantities, helictites form. If there is more water, a bulbous form results. However, no one really knows for sure the real reason that bulbous stalactites form by.
Soda Straws in the Lodge Room area have been observed with bubbles on their tips during wet periods in early spring. Bubble-blowing stalactites are thought to be caused when internal flow in a soda straw is temporarily interrupted while external flow continues. This can draw water and air into the straw. When internal flow resumes, the result will be a bubble on the end of the soda straw with water dripping from the bubble.
Last updated: February 28, 2015