The collected and studied diamonds from the mines in South Africa, China, Zaire and Sierra Leone scientists from the University of Nevada (USA) found a microscopic inclusion of ice very rare cubic form. Such ice is called ice VII. This finding may lead to a reassessment of our ideas about the amount of water hidden in the bowels of the Earth, the researchers published in the journal Science article.
Scientists say that almost all the ice with which we deal in everyday life, for example, from the same fridge, are presented in the form of ice-Ih, has a hexagonal crystal lattice. In General, there are dozens of other phases of ice that can form when various unusual conditions. These include the ice-VII has a cubic crystal lattice. As a rule, it occurs in outer space, but on Earth it managed to get only in laboratory conditions, with extremely high temperatures and pressures.
However, a team of mineralogists from the University of Nevada under the leadership of Oliver Zauner discovered the first natural samples of ice-VII. Scientists believe that the formation of these crystals occurred at depths 610-800 kilometers, where, as previously considered, there is no presence of water. Thus to explain its presence there is possible only by the fact that the inclusion of water could sink deeper under the surface, and increasing with the temperature and the pressure eventually led to the formation of ice VII.
This is the transitional boundary between the upper and lower mantle of the Earth, and deeper of her. While it is difficult to say how much water there may be, but its very presence will force geologists to reconsider the energy balance of the mantle and the processes developing it in rocks.
The mineralogists found in terrestrial diamonds “alien” ice
Nikolai Khizhnyak