Tag: Gneiss
Metamorphic facies: what is it?
The study of metamorphic rocks is essential to understanding the tectonic history of a region. We are talking about metamorphism when a rock, whatever it is, undergoes a transformation linked…
Migmatitis: what is it?
Under certain conditions of pressure and temperature, the rocks that make up the continental crust can melt. However, the rocks of the earth’s crust have very varied compositions. They are…
Protolith: what is it?
Some geological processes, such as metamorphismmetasomatism or chemical weathering, lead to the transformation of all types of rocks, designated as protoliths, into rocks of a different nature. The protolith therefore…
Gneiss: what is it?
The gneiss is a metamorphic rock composing the continental crust. It mainly contains quartz, micas, feldspars plagioclases and sometimes alkaline feldspars. The color of the rock is variable, but often…