Mount Sinai's rocks were formed in the late stage of the Arabian-Nubian Shield's (ANS) evolution. Mount Sinai displays a ring complex that consists of alkaline granites intruded into diverse rock types, including volcanics. The granites range in composition from syenogranite to alkali feldspar granite. The volcanic rocks are alkaline to peralkaline and they are represented by subaerial flows and eruptions and subvolcanic porphyry. Generally, the nature of the exposed rocks in Mount Sinai indicates that they originated from differing depths.