What do stalagmites look like?
The stalagmite root is 3m high, with a round column, a thick top and a thick bottom. It is carved with white granite and is made of four sections, with a simple shape.
stalagmites are formed by water full of calcium carbonate dripping to the bottom of the cave through cracks at the top of the cave or from stalactites. On the one hand, the water evaporates; on the other hand, the amount of CO2 dissolved in water decreases due to the high temperature in the cave sometimes, so calcium precipitates and deposits at the bottom of the cave.
Over time, stalagmites grow from bottom to top, and stalactites grow from top to bottom. Stalagmites are unearthed like bamboo shoots and grow from bottom to top. Stalagmites and stalactites grow slowly, about one meter long and one meter high in ten thousand years. Stalagmites are formed by the continuous dripping of water containing carbonic acid to one place and the precipitation of calcium carbonate. It can have different shapes, and the flow rate of water droplets, the height of water droplets and the condition of the ground will all affect the shape of stalagmites.
stalagmites respond to climate change
Stalagmites generally grow every year except in particularly dry years, when the roof of the cave stops dripping. With the change of seasons, the water dripping from the cave top contains different substances, so that stalagmites, like tree rings formed by trees, will form their own annual rings, and the age of stalagmites can be counted through the annual rings. Many stalagmites were formed a long time ago, and the stalagmites stopped growing because there was no dripping water, so they became "dead" stalagmites, and researchers have a way to accurately date the growth of these stalagmites.
With the climate change, the substances contained in calcareous stalagmites will also change. Scientists can recover the past climate change by measuring the changes of these substances. There are many limestone caves in China, in which a large number of stalagmites grow, which have become important materials for paleoclimate research. For example, Dongge Cave in Guizhou, Hulu Cave in Nanjing and Wanxiang Cave in Gansu are all geomantic treasures for studying ancient climate by using stalagmites.