What is lava? Varieties of lava

The question of what is lava is of interest to manyscientists for a long time. The composition of this substance, as well as its shape, speed of movement, temperature and other aspects have become the subject of a number of research and scientific works. This can be explained by the fact that its frozen streams represent almost the only source of information on the state of the Earth's interior.

General concept

First, you need to understand what is lava inmodern understanding? Scientists call it material in the molten state, located in the upper part of the mantle. While in the earth's interior, the composition of the substance is uniform, but as soon as it approaches the surface, the process of boiling begins with the release of gas bubbles. It is they who move the incandescent material towards the cracks in the crust. In this case, not all of the liquid erupts to the surface. Speaking of what the meaning of the word "lava" is, it should be noted that this concept extends only to the outflowing part of matter.

Basalt lava

The most common species on our planetis basaltic lava. Most of all the geological processes that took place on Earth many thousands of years ago were accompanied by numerous eruptions of this type of hot substance. After its hardening, a black rock of the same name was formed. Half of the composition of basaltic lavas is aluminum oxide, magnesium, iron and some other metals. Due to them, the temperature of the melt reaches a mark of about 1200 degrees. At the same time, the lava flow moves at a speed of about 2 meters per second, which is comparable to the running man. As the research shows, in the future on so-called "hot trails" they move much faster. Basalt lava from the volcano is not very thick. It flows quite far (up to several tens of kilometers from the crater). It should be noted that this species is characteristic for both land and ocean.

Acidic lava

In the case when a substance is present63% or more of silica, it is called acidic lava. The red-hot material is very viscous and is practically incapable of flowing. The speed of flow often does not even reach a mark of several meters per day. The temperature of the substance in this case is in the range of 800 to 900 degrees. With melts of this kind, the formation of unusual rocks (ignimbrites, for example) is associated. If the acid lava is saturated with gas, it boils and becomes mobile. After ejection from the crater, it quickly flows back to the resulting cavity (caldera). The consequence of this is the appearance of pumice - an ultra-light material, whose density is less than that of water.

Carbonate lava

Talking about what lava is, many scientists beforeNow they can not determine the principle of the formation of its carbonate variety. This substance includes potassium and sodium carbonates. It erupts only one volcano on the planet - Oldoino-Lengai, which is in the territory of Northern Tanzania. Carbonate lava is the most liquid and cold of all existing species. Its temperature is about 510 degrees, and it moves along the slopes with the same speed as water. Initially, the substance has a dark brown or black color, but after a few hours of being outside it becomes lighter, and after a few more months it completely whitens.

conclusions

Summing up, it is necessary to focus attention onThe fact that one of the most acute geological problems is associated with lava. It consists in the fact that this substance warms up the earth's interior. Fires of hot material rise to the earth's surface, after which they melt it and form volcanoes. An unequivocal answer to the question of what lava is, even leading world scientists can not give. At the same time, it can be stated for certain that it is only a small part of the global process, the driving force of which is hidden very deep beneath the earth.