The Afar Triangle (also called the Afar Depression) is a geological depression that is caused by the Afar Triple Junction, which is part of the Great Rift Valley. It overlaps Eritrea, Djibouti and the entire Afar Region of Ethiopia. The depression is bordered by the Ethiopian Plateau and escarpment to the west, by the Danakil block to the north-east (between it and the Red Sea), by the Somalian Plateau and escarpment to the south, and by the Ali-Sabieh block (adjoining the Somalian Plateau) to the south-east.