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The Growth Of Stalactites: The growth of stalactites and stalagmites is usually extremely slow. Some take 4,000 years to increase by only 2.5cm (lin) in length. However, stalactites in Ingleborough Cave, Yorkshire, have been known to increase by 7.6cm (3in) in ten years.
Another deposit, caused by water seeping through a long crack in the Roof of a cave, is a wavy band of calcium carbonate which grows across the ceiling like a fringed curtain. Water flowing down a Wall or across a Floor of a cave may build up a flowstone.
Limestone caves contain many features formed from deposits of calcium carbonate, including icicle-like stalactites [6] and pillar-like stalagmites [5]. Stalactites develop when water that is highly charged with dissolved calcium bicarbonate seeps through holes in the roofs of caves. Drops of water that hang on the Roof are partly evaporated and a tiny quantity of calcium carbonate is precipitated and sticks to the roof. Another drop of water deposits a second film of calcium carbonate in the same place and, in this way, stalactites slowly develop.
Lateral growth in trees frequently begins later than growth in height, but the period of lateral growth is longer. Rates of lateral growth likewise are low at the outset, increasing after a few weeks and then diminishing. In view of the long annual period of lateral growth in trees, deleterious environmental conditions may exercise a pronounced effect on growth. In the wood of trees of temperate regions, narrow and wide growth rings may be observed, marking years characterized by unfavorable and favorable conditions for growth. |
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