Jabal Tuwaiq (, Tuwaiq Mountain) is a narrow

escarpment An escarpment is a steep slope or long cliff that forms as a result of faulting or erosion and separates two relatively level areas having different elevations. Due to the similarity, the term '' scarp'' may mistakenly be incorrectly used inte ...

that cuts through the plateau of

Najd Najd is a Historical region, historical region of the Arabian Peninsula that includes most of the central region of Saudi Arabia. It is roughly bounded by the Hejaz region to the west, the Nafud desert in Al-Jawf Province, al-Jawf to the north, ...

in central

Arabia The Arabian Peninsula (, , or , , ) or Arabia, is a peninsula in West Asia, situated north-east of Africa on the Arabian plate. At , comparable in size to India, the Arabian Peninsula is the largest peninsula in the world. Geographically, the ...

, running approximately from the southern border of Al-Qasim in the north, to the northern edge of the Rub' al Khali desert near Wadi ad-Dawasir in the south. It is high and also has a

Middle Jurassic The Middle Jurassic is the second Epoch (geology), epoch of the Jurassic Period (geology), Period. It lasted from about 174.1 to 161.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relativel ...

stratigraphic section A stratigraphic section is a sequence of layers of rocks in the order they were deposited. It is based on the principle of original horizontality, which states that layers of sediment are originally deposited horizontally under the action of ...

. The eastern side slopes downwards gradually, while the western side ends in an abrupt manner. The escarpment can be thought of as a narrow plateau, though the locals refer to it as a ''jebel'' ("mount").

Marshall Cavendish Marshall Cavendish is a subsidiary company of Times Publishing Group, the printing and publishing subsidiary of Singapore-based conglomerate Fraser and Neave (which in turn currently owned by ThaiBev, a Thai beverage company), and at present i ...

used the name "Tuwayr Mountains" to describe mountains of central Arabia, distinct from the

Shammar The tribe of Shammar () is a tribal Arab Qahtanite confederation, descended from the Tayy, which migrated into the northern Arabian Peninsula from Yemen in the second century. It is the largest branch of the Tayy, and one of the largest and mos ...

in the north, the Dhofar in the south, and the Hajar to the east. Many narrow valleys (''

wadi Wadi ( ; ) is a river valley or a wet (ephemerality, ephemeral) Stream bed, riverbed that contains water only when heavy rain occurs. Wadis are located on gently sloping, nearly flat parts of deserts; commonly they begin on the distal portion ...

s'') run along its sides, such as

Wadi Hanifa Wadi Hanifa (), historically known as Wadi al-Arad, is a ''wadi'' (seasonal river) in the Najd region, Riyadh Province, in central Saudi Arabia. The valley runs for a length of from northwest to southeast, cutting through the city of Riyadh, ...

, and a group of towns lie on its central section, including the Saudi capital,

Riyadh Riyadh is the capital and largest city of Saudi Arabia. It is also the capital of the Riyadh Province and the centre of the Riyadh Governorate. Located on the eastern bank of Wadi Hanifa, the current form of the metropolis largely emerged in th ...

. Many settlements have historically existed on either side of it as well, such as those of

Sudair Sudair or Sudayr () is a historical region in Najd in the central of Saudi Arabia, and is located approximately 150 km north of the Saudi capital, Riyadh. The region lies in a valley directly to the east of the Tweig escarpment, which runs ...

and Al-Washm. The Tweig escarpment is mentioned in Yaqut's 13th century geographical encyclopedia under the name "Al-'Aridh", though for the past few centuries that name has applied only to the central section of it, around Riyadh.

Tourism

In the framework of the recent Saudi tendency to promote entertainment, a group of 100 young hikers joined Tuwaiq Mountains Challenge in February, 2019. The hikers climbed around 25km.

Petroleum geology

The Arab-D ( Upper Jurassic) unit of the Riyadh Group makes up one of the largest

petroleum reservoir A petroleum reservoir or oil and gas reservoir is a subsurface accumulation of hydrocarbons contained in porous or fractured rock formations. Such reservoirs form when kerogen (ancient plant matter) is created in surrounding rock by the prese ...

s in the world. Bureau and Saudi Aramco researchers conducted a high-resolution LIDAR survey of Middle Jurassic outcrops of the Tuwaiq Mountain limestone along the Tuwaiq Mountain Escarpment near the city of

Saudi Arabia Saudi Arabia, officially the Kingdom of Saudi Arabia (KSA), is a country in West Asia. Located in the centre of the Middle East, it covers the bulk of the Arabian Peninsula and has a land area of about , making it the List of Asian countries ...

. This study was a first step towards building a quantitative 3-D geologic model for use as an analog to the lower Arab-D reservoir. Outcrop analogs like this one are critical to understanding reservoir performance on the flow-unit scale (1 to ). Although seismic data allow geologists to gain information about large-scale reservoir compartmentalization (>), flow-unit scale reservoir parameters are far below seismic imaging capability and inter-well spacing. High-precision laser scans were used as a template upon which stratigraphic interpretation were made allowing researchers to characterize sub-seismic, flow-unit scale reservoir properties of Jurassic bioherms in an effort to better understand optimum production techniques of this enormous reservoir.

Gallery

File:Along the Ridge (2993423284).jpg, Along the ridge File:Desert canyon (3344010623).jpg, Desert canyon File:Riyadh-Makkah Road near Tuwaiq Escarpment.JPG, The

highway A highway is any public or private road or other public way on land. It includes not just major roads, but also other public roads and rights of way. In the United States, it is also used as an equivalent term to controlled-access highway, or ...

from Riyadh to

Makkah Mecca, officially Makkah al-Mukarramah, is the capital of Mecca Province in the Hejaz region of western Saudi Arabia; it is the holiest city in Islam. It is inland from Jeddah on the Red Sea, in a narrow valley above sea level. Its metropo ...

File:Tuwaik escarpment-15h23m15s-s.jpg, People at the base of the escarpment File:Tuwaiq Escarpment (2981960802).jpg, Looking out from the edge of the Tuwaiq Escarpment, west of Riyadh

References

External links

Mountains of Saudi Arabia Historical regions in Saudi Arabia {{Saudi-geo-stub

Tourism

Petroleum geology

Gallery

See also

References

External links