The Kondyor Massif is a perfectly circular geological formation in Eastern Siberia, Russia, roughly 600 km west-to-southwest of Okhotsk, or some 570 km south-east of Yakutsk. From space it looks like an impact crater or the caldera of an extinct volcano, but Kondyor Massif is neither. It is what geologists refer to as an “intrusion”.

An intrusion forms when molten magma of igneous rock crystallizes below the surface of the earth, and is slowly pushed up through the earth’s mantle, a process that can take millions of years. As the rock slowly cools into a solid, the different parts of the magma crystallize into minerals. Because the magma solidify underground before they reach the surface of the crust, they are also called “plutons”, in honor of the Roman god Pluto, the king of the underworld.

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