Tag: Earth’s crust
Silica: what is it?
Silicates are an important family of minerals which represent nearly 95% of the constituents of Earth’s crust. This family includes about 600 species different minerals, whose atomic architecture is characterized…
MORB: what is it?
The term MORB, for Mid-Oceanic Ridge Basalt (basalt mid-ocean ridge, in French) refers to basalts with the typical chemical composition of those formed at ridges. In particular, they make up…
OIB: what is it?
The term OIB, for Ocean Island Basalt (Where basalt of an oceanic island), refers to basalts having the typical chemical composition of those formed at the level of hot spotsor…
Dike: what is it?
Dykes are intrusions of igneous rocks within the Earth’s crust. Unlike the plutos, which form massive sets, the dykes are in the form of veins which cut the rocks of…
Sill: what is it?
Sills are intrusions of igneous rocks within the Earth’s crust. Of tabular geometry, they are in the form of let’s go horizontal, which insinuate themselves between older surrounding sedimentary layers.…
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…
Is the Martian crust different from the Earth’s crust?
On a large scale, the internal structure of Mars appears quite similar to that of Earth. But what about in detail? The InSight mission to Mars provides us with details…
Lava lakes seen by Olivier Grunewald
Windows open towards the center of the Earththe lakes of wash are fascinating phenomena. Often located at the bottom of deep craters, their dynamism is hypnotic. The regular arrival of…
What is the composition of the continental crust?
Our Planet is made up of different geological envelopes, the best known of which is certainly the one we have under our feet: the continental crust. Often considered as an…