The peninsula of Qatar is low-lying. Its shape is the surface expression of the
anticlinal Qatar Arch, formed during the
Precambrian Amar Collision about . It is enveloped by loose sand and pebbles broken off the outcropping
limestone. Smooth plains covered by fine-grained dust are found in the east, while the south and south-west portions of the peninsula mainly comprise
sand dunes and
salt flats (locally known as
sabkhas), particularly near
Mesaieed and
Khor Al Adaid. Sakbahs can also be found in western Qatar, near
Dukhan and
Sawda Natheel. For purposes of categorization, the country is divided into five principal regions: coastal plain, interior plain, central belt, Dukhan region, and southern desert. and accommodates the lowest point of Qatar at below sea level.
Jebel Nakhsh, a notable
mountain ridge south of Dukhan, contains substantial deposits of
gypsum.
Southern desert This region occupies 34.7% of Qatar's total area, south of Doha's latitude. It bears topographical similitude to the desert areas of
Abu Dhabi,
Saudi Arabia, and
Bahrain, with undulating sand dunes interspersed with rocky
hamada surfaces. It is divided into four sub-regions: • Al Urayq: A triangular area in the extreme west, with its apex at Abu Samra. Its northern side aligns with the southern extremity of the Doha-Abu Samra road, and its southern side follows the border line from Abu Samra towards the southeast. • Miocene-Tiwar: Characterized by isolated hills amidst a rocky plain. The hills reach a maximum of and include Qatar's highest point,
Qurayn Abu al Bawl. This sub-region is concentrated in the southwestern part of the Qatar Peninsula, including areas like
Mukaynis,
Al Kharrara, and
Wadi Jallal. • Rocky surfaces: Consisting of expanses of exposed bedrock, often weathered into flat, stony plains known as desert pavements. The surface may be covered by a mosaic of closely packed pebbles and rock fragments, or in some places by a thin layer of indurated mineral deposits forming a hard crust. This sub-region is divided into two units: one shaped like a trapezoid bounded by the water pipeline passing through
Abu Nakhla to Mesaieed, and another extending from Umm Jawlaq southeastward through Al Khubayb, Al Fulayhah, and Umm Al Hayran to Khor Al Adaid. • Sand dunes: Occupying 1.6% of Qatar's area, with dunes reaching heights of to . Interspersed among the dunes are numerous closed basins with floors varying in elevation from to metres above sea level, resulting in an undulating topography. The northern boundary of this sub-region aligns with the latitude of Umm Owaina. ==Landforms==