Crust (geology) crustal rocks formed before 2.5 billion years ago are located in cratons. Such old continental crust and the underlying mantle asthenosphere are less dense than elsewhere in Earth and so are not readily destroyed by subduction. Formation of new continental crust is linked to periods of intense orogeny; these periods coincide with the formation of the supercontinents such as Rodinia, Pangaea and Gondwana. The crust forms in part by aggregation of island arcs including granite and metamorphic fold belts, and it is preserved in part by depletion of the underlying mantle to form buoyant lithospheric mantle. A theoretical protoplanet named
Finn (given name) Finn (given name) Finn is generally regarded as a masculine given name. The name has several origins. In some cases it is derived from the Old Norse personal name and byname "Finnr", meaning "Lapp" or "Finn". In some cases the Old Norse name was a short form of other names composed with this element. In other cases, the name "Finn" is derived from Irish, meaning "white" or "fair". In the later case, the name is an earlier Irish variant of "Fionn". It is also occasionally a female given name, although this is less common. People with the given name include: