Kivilajiryhmien

Kivilajiryhmien, which translates to "rock type groups" in Finnish, is a classification system used in geology to categorize rocks based on their origin and formation. This system divides all rocks into three main categories: igneous, sedimentary, and metamorphic.

Igneous rocks are formed from the cooling and solidification of molten rock, either magma below the Earth's surface or lava on the surface. Examples include granite and basalt.

Sedimentary rocks are formed from the accumulation and cementation of mineral and organic particles, or by the precipitation of minerals from water. These rocks often contain fossils and exhibit layering. Sandstone and limestone are common examples.

Metamorphic rocks are formed when existing rocks, whether igneous, sedimentary, or other metamorphic rocks, are transformed by heat, pressure, or chemical reactions. This transformation occurs without the rock melting. Marble and slate are examples of metamorphic rocks.

The kivilajiryhmien classification is fundamental to understanding Earth's geological history, the processes that shape the planet, and the resources that can be derived from rocks. By examining the characteristics of a rock, geologists can determine which group it belongs to and infer the conditions under which it formed. This system provides a framework for studying rock cycles and the dynamic nature of the Earth's crust.