I remember at school, in a geography lesson, they did not explain how diamonds were formed. Allegedly, this happened during the fall of asteroids in distant eras. A pressure jump was formed in the earth's crust and crystalline forms of carbon appeared in these layers. This is the so-called meteorite hypothesis of the origin of diamonds.
Everyone knows that graphite and diamond are chemically the same. But the crystal lattice of the arrangement of atoms is different. Allegedly, high pressure is responsible for such a crystal lattice, for the appearance of diamonds.
There is a magmatic hypothesis of the formation of diamonds, which says that they formed in the depths of the Earth and were carried to the surface by fluids. But it is known that at elevated temperatures, diamond turns into graphite. So this hypothesis is questionable.
Diamonds are found on all continents (except Antarctica, but perhaps they have not yet been found because of the ice) in loose deposits. But large deposits are contained in the so-called kimberlite (90%) and lamproite (10%) pipes.
Kimberlite is igneous rock interspersed with xenoliths. Also called explosion tubes.
The pipe is Lucky.
Promotional video:
They go to great depths. Most likely, they have nothing to do with the impact, shock origin. Because the pressure created by the impact of the asteroid would decrease with depth and the diamonds would no longer form deep. They refer to processes in the bowels of the Earth.
There is a hypothesis by geologist Natalia Sarsadskikh, who says that the rock of kimberlite pipes is just a transport for diamonds to the surface, that the diamonds themselves were not formed in it.
The Ekati kimberlite pipe in Canada.
Man has learned to artificially create diamonds. The main method is a graphite-metal mixture shock. And the gas-plasma method from a mixture of gases (hydrogen, propane) - is the growth of diamonds on the substrate in this high-frequency plasma.
But it turns out that at the end of the 19th century. there was such a method:
World Illustration magazine. It's a theory or not, it's hard to say now. But the method is simple, it can be repeated in almost any laboratory.
Based on this, it can be assumed that the once liquid kimberlite, emerging as a magmatic dike to the surface, was blown through by a mixture of gases. And in this environment, diamonds grew from the melt with gases. This is why kimberlite pipes are tube-shaped. These are pipes for degassing subsoil.
There is evidence that the Udachnaya kimberlite pipe in Yakutia emits up to 100 thousand cubic meters of gas daily. Apparently, these are residual phenomena from the powerful degassing of the subsoil in the past. But what happened that in those days the inner structure of the planet was so actively destabilized?
Author: sibved