The botanical gardens of Beijing and several scenic spots on the outskirts of Beijing are majestically standing with some petrified giant trees. I once heard a little boy ask how trees turn into stone, and his father replied in seconds: pouring cement is stone.
All right. His father had a point.
Petrification, this is an anomaly in fantasy - although there are monsters in the "Classic of Mountains and Seas", we are more familiar with Medusa's gaze.
No imagination can go beyond reality, and until modern science explains how fossils are formed, petrification magic is a good explanation.
Now we understand that it includes mineralization, molding, displacement, recrystallization, pressurization, carbonization, etc"Mathematical, physical and chemical magic"Fossils are created.
Some petrification magic doesn't last long. In recent years, a group of posing photos has been very popular, the calcified bird of Lake Natron in Africa - the water source of the lake is extremely alkaline, and the pH value is as high as 105。
In addition to the eye-catching calcified bird, petrification is the process by which organic matter becomes by replacing the original substance and filling the pores, crevice spaces with minerals.
The geological history of our planet is similar to that of human civilization – long and turbulent – with periods of mass upheaval and destruction alternating with periods of relative calm.
Life on Earth has evolved through all these changes and has thrived for 4 billion years despite experiencing mass extinctions, leaving behind magnificent physical traces of the past.
Petrified trees are the quintessential and most spectacular example of this process – they are so beautifully preserved that one needs to look and touch them a few more times before they realize that they have indeed turned to stone.
Petrified trees are not uncommon among fossils and are found in many places on all continents, even Antarctica.
Petrification literally means the process of turning living tissue into stone. This requires two related mechanisms: the deposition of minerals in the living tissue space; Organic molecules (in the case of wood, mainly cellulose and lignin, which make up the cell walls of wood, and pectin, which binds the cells together) are actually replaced by minerals.
What minerals?
Silica – mainly silica in the form of opal, chalcedony, or quartz.
Silicification begins within the cell wall, and the space within and between cells is gradually filled with silica.
Over time, almost all of the original organic matter in the tree disappears, becoming pure silica, with small amounts of metallic elements such as iron (color on top).
Both processes of mineralization and displacement take time, ranging from tens to millions of years. The oldest known petrified tree is about 38.5 billion years old.
Petrochemicals can also be as short as 100 years, subject to two conditions: the plant tissue must not decay before mineralization; The (water) environment must be extremely rich in minerals.
The elimination of oxygen is the most important factor in the preservation of wood tissue: oxygen is necessary for the life processes of organisms that break down lignin. Burying in mud is a good option.
While it is theoretically possible to make petrified wood by pouring cement, the perfect scenario in nature is for lava from a volcanic eruption to carry trees into the lake. The boiling of water and the cooling of lava will create conditions for large quantities of logs to be buried, preserved, and mineralized.
Interestingly, if you throw wood into the saline lake that produces calcified birds at the beginning of the article, the wood will disappear very quickly - wood in an alkaline environment will quickly decompose due to inorganic reaction with alkali.
Petrification requires a special environment, and petrified trees are the embodiment of the laws of ordered chemistry. Next time, see these fossils that we ordinary people can touch casually, and remember that we are part of an awesome world.
The author thanks for your interest (-
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