The Al Haruj al Aswad ("Black mountain") field in the northern part of Haruj and Al Haruj al Abyad ("White mountain") south are considered to be subdivisions of the main Haruj volcanic field with Aswad covering a much larger surface than Abyad, or even two separate volcanoes that started overlapping each other during the Pliocene.
The Al Haruj al Aswad ("Black mountain") and Al Haruj al Abyad ("White mountain") areas in Haruj are considered to be parts of a larger volcanic field. The Aswad area covers more ground than Abyad, or it may even represent two separate volcanoes that started merging during the Pliocene.