Petrology facts for kids

The black rocks are "pelite", a metamorphosed fine-grained sedimentary rock, like mudstone or siltstone.

Petrology is a super cool part of geology. Geology is the study of Earth! Petrology is all about rocks. It looks at what rocks are made of, how they look, and how they are put together. It also studies the special conditions needed for rocks to form. Think about how a rock might form deep inside a volcano or at the bottom of an ocean!

Types of Rocks and Petrology

There are three main types of rocks. Petrology has a special branch for each type. There is also a branch that uses experiments to learn more about rocks.

Igneous Rocks and Petrology

Igneous rocks form from molten rock. This molten rock is called magma when it's underground. When it erupts from a volcano, it's called lava. Igneous petrology studies these rocks. Examples include granite and basalt. These rocks can form from volcanoes or deep inside the Earth (plutonic rocks).

Sedimentary Rocks and Petrology

Sedimentary rocks form from bits of other rocks, minerals, or living things. These bits are called sediments. Over time, sediments get pressed and cemented together. Sedimentary petrology studies these rocks. Examples include sandstone, shale, and limestone.

Metamorphic Rocks and Petrology

Metamorphic rocks are rocks that have changed. They change because of extreme heat, pressure, or chemical reactions. This happens deep inside the Earth. Metamorphic petrology studies these changed rocks. Examples include slate, marble, gneiss, and schist.

Experimental Petrology

Experimental petrology is a branch that uses special labs. Scientists use machines that create very high pressures and temperatures. They do this to see how rocks and minerals behave. This helps them understand how rocks form in Earth's deep interior.

Images for kids

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  A volcanic sand grain seen under the microscope, with plane-polarized light in the upper picture, and cross-polarized light in the lower picture. Scale box is 0.25 mm.

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  Ljudmila Dolar Mantuani (1906-1988) first female professor of petrography in Yugoslavia.

See also

In Spanish: Petrología para niños