Ras Muhammad Marine National Park is located on faulted and uplifted Neogene blocks that are partially covered by Quaternary limestones of predominantly coralgal facies. The physiography of the reefal limestone cropping out in the area and also the present-day depositional environments are tectonically controlled. Surface morphology observations show that earthquake pools that cut through the uplifted Pleistocene reefs indicate continuing recent movements, as indicated by numerous records of seismic activity in the study area. The morphostructural-generated depositional facies patterns on the peninsula are a wide tidal belt with tidal shoals and coastal spits, barrier and fringing reefs, three elongated embayments, Hiddan Bay, mangrove and tidal channels, Ras Muhammad pool and sabkha, and earthquake pools (two earth fissures). The distribution of marine plants is described for each area. The abundance of algae in Ras Muhammad appeared to be inversely related to the abundance of living corals.