Deep in the earth, in mysterious caves far from human hands, these caves had their own strange and special ways to record time with the passage of time.
Within these caves there is something that distinguishes them strongly, they are stalagmites and stalactites, or ascending columns and overhangs. Which grows very slowly. The average growth of droppers is estimated at 0.13 mm per year, and their rate of growth can reach 3 mm per year. Read also For the first time … a team of scientists has chronicled the climate via a pile of bat guano Scientists are finding evidence confirming the oldest human activity everIt dates back 30,000 years … an amazing cave that changes the history of human existence in North AmericaIn side a cave in California … the first evidence of humans eating hallucinogenic plants
Stalactites and stalactites
The ascending columns consist of calcium carbonate that accumulates on the floor of the cave due to the trickle of mineral water over a long period of time. The stalactites that hang from wet cave roofs are also formed in such a way as to form the stalagmites themselves. The color of each depends on the type of ores that are included in the cave stone formation.
Stalactites and stalactites are beautiful formations that attract tourists to watch them, but it is not permissible to touch these formations by hand because sweat and fat disrupt the precipitation of water on them, and may also change their color. Some of these stalagmites are 62 meters long, as is the case in the Suiba San Martin cave in Cuba.
Each pendulum begins with the drip of one drop of water loaded with mineral salts, then a second point, then a third, and so on in the same place, and when the drops fall, they leave a thin stuck of calcite. Each other deciduous point forms another ring of calcite.
With the successive precipitation and calcite deposition, the conical shape typical of pendentives is formed. The same water droplets fall from hanging on the ground, forming conical stalagmites erecting on the ground, and over time, these stalagmites may enlarge, forming compact columns.
The ancient recorded past
Scientists have previously tried to discover how much ancient past was included in these underground formations, such as ancient forest fires and other natural disasters and crises. However, in a new study published in Reviews of Geophysics, researchers have found more.
The researchers, led by geochemist Andy Baker of the University of New South Wales in Australia (UNSW in Australia), found that stalagmites not only record dramatic states of sudden and extreme weather events, but also act as natural timekeepers, consistently chronicle the passage of time in layers of rock. Formed.
“Our new global analysis shows that we can consider the growth of stalagmites as like a very constant velocity pendulum over hundreds and thousands of years,” Baker says in the report published on Science Alert.
“In general, the growth of stalagmites can be predicted, and it is this unique property that makes them so valuable to researchers. You can tell the time in the past by using very regular growth rings that are widely found around the world,” he adds.
23 caves on 6 continents
During their study, Baker and his team analyzed stalagmites from 23 caves across 6 continents, looking for any common mechanisms that might explain their evolution. They found that the growth rates of stalagmites increased in line with warmer temperatures, and that the formations appeared to only grow in regions with monsoons. Advertising
While many climatic disturbances can affect stalagmite growth methods, once these severe disturbances pass, the rate of growth over time is common and relatively consistent around the world. The average height of global stalagmites has increased by about 1 meter over the past 11,000 years, Baker says.
Stalagmites generally grow in an orderly manner, just like tree rings, except in cases where long-term, multi-year disturbances appear, such as long wet or dry years associated in the record with events such as El Niño or La Niña events.
When these disturbances end and pass, the growth layers of the stalagmites return to their usual rhythm, consistent with the humidity descending on them from above.
The researchers emphasized in their research paper that “the rate of stalagmite accumulation does not change relatively over time, because the source of the drip water has enough volume and stable chemical composition to be a buffer for rapid changes.”
For these reasons, the researchers say stalagmites have a lot to learn about the chronology of the ancient past, with an extensive archive of intermediate climate data that we are just starting to explore.