The Fen Complex (Norwegian: Fensfeltet) in Nome, Telemark, Norway is a region noted for an unusual suite of igneous rocks. Several varieties of carbonatite are present in the area as well as lamprophyre, ijolite and other highly alkalic rocks. It is the type locality for fenite, a metasomatic rock commonly found around carbonatite and alkali intrusives. The complex is a protected location because of the rare minerals and rock types found there. The rocks were first described by Waldemar Christofer Brøgger in 1921.