Musandam Peninsula and Straits of Hormuz

Abstract

The Musandam peninsula is the northernmost promontory of the Oman–UAE Mountains and one of the most distinctive geological features of eastern Arabia (Figs. 6.1 and 6.2). The Straits of Hormuz between Kumzar in Omani Musandam and Qishm Island in Iran is only 50 km wide. The Straits of Hormuz separates the Arabian Gulf to the west from the Gulf of Oman (or Sea of Oman) to the east. The 650 km winding coastline has some unique geomorphology with steep cliffs dropping straight into the ocean, large fjords cutting deep into the mountains and numerous sandy bays and small islands. Late Cenozoic eastward tilting of the entire Musandam peninsula has resulted in a spectacular geomorphology with drowned wadi systems along the north and east coasts creating fjords with sea-cliffs hundreds of meter high. The highest peaks of the Musandam, including Jebel Yibir, are just over 2000 m above sea-level and lie only 4–6 km from the east coast. The main wadis drain westward to Ras al Khaimah (Wadi al Bih, Wadi Ghalilah, Wadi Sham) and northwest to Khasab (Wadi Sal al A’la). Two large fjords cut through the northern Musandam mountains, Khawr As Shaam from the Arabian Gulf and Khawr Habalayn–Khawr Najd from the Gulf of Oman side. A narrow isthmus of mountainous land less than 900 m wide separates the two fjords. The fantastical winding coastline of the northern Musandam testifies to the Quaternary and Recent tilting of the entire peninsula to the east and north. The Royal Geographical Society carried out a major geographical research project in the Musandam peninsula during 1971–1972 (Cornelius et al. 1973).