Rapid growth does not take millions of years
Rapid stalactite growth in Siberia By David Lewis Subscribe Natalya Polina was showing me around a geological museum in southern Siberia. She explained, “This is a cross-section from a stalactite. The rings show how much it has grown each year”.1 My interest was aroused by a very wide ring which grew well over a centimetre in one year (see picture on the right). “What causes the rings?” I asked Natalya. “The dirt that surface water carries into the cave varies between summer and winter,” she replied. “There is more dirt in summer so a dark ring is deposited, whereas in winter, when…