As a result, it is heavily vegetated, and for much of the year is green and lush. The inhabitants of the villages and communities on the jebel are known as jibalis (hill people). To the north, the hills slope down via rough wadis and cliffs into the gravel plains and sand seas of the Empty Quarter.In January 1974, after several splits and defections, the rebel movement renamed itself the Popular Front for the Liberation of Oman.