Rare earths

Published May 18, 2018

Rare earths

In the everyday life of the industry today, you can often find such rare metals like titanium, tantalum, cesium, molybdenum, hafnium and zirconium. But there were times when no one heard anything about them, and knew almost nothing. The same fate was experienced by rare earths - a group of chemical elements, among which the main ones are cerium...

The territory of permafrost

Published May 18, 2018

The territory of permafrost

The territory of permafrost on Earth is approximately 25 million square kilometers. In this case, the thickness of the permafrost layer varies - on average about a kilometer, but reaches two. Do not be her - battery and moisture custodian - huge spaces North American and Asian continents, where there is little precipitation, would be turned into a desert...

The upper mantle of the Earth

Published May 18, 2018

The upper mantle of the Earth

According to different sciences, the model of a multi-storey device is known Earth: bark, lying from the surface to 15-70 km, then the mantle, which is below 2900 km is replaced by the core of the planet. The density mantle is divided into three parts: the upper, or asthenosphere (50-400 km), medium, or transitional (400-1000 km), lower (1000-2900 km)...

Crater of the volcano

Published May 18, 2018

Crater of the volcano

To the west of the volcano Kilimanjaro, at a distance of about 300 km, one of the most amazing wonders of Africa - the long-extinguished crater of the volcano Ngorongoro - is located. The crater of the volcano Ngorongoro was formed about 2 million years ago as a result of a powerful explosion that carried the top. It is a deep hollow...

Internal waves of the ocean

Published May 18, 2018

Internal waves of the ocean

It turns out that in the depths of the World Ocean can, as well as in the atmosphere, strong storms are played out, which are a possible cause from time to time underwater submarine disasters. Many experts believe that the so-called internal waves of the ocean that are caused, spread and decay in the depths...

The lime

Published May 18, 2018

The lime

One of the most common minerals of the outer part of the earth's crust is the carbon dioxide lime, which forms mountains of limestone and marbles, in a large number is included in the composition of soils and marls. Lime is dissolved in river waters and sea water...

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