TheDrakensberg (Zulu: uKhahlamba,Sotho: Maloti,Afrikaans: Drakensberge) is the eastern portion of theGreat Escarpment, which encloses the centralSouthern African plateau. The Great Escarpment reaches its greatest elevation – 2,000 to 3,482 metres (6,562 to 11,424 feet) within the border region ofSouth Africa andLesotho.
A map of South Africa shows the central plateau edged by the Great Escarpment and its relationship to theCape Fold Mountains to the south. The portion of theGreat Escarpment shown in red is known as the Drakensberg.
The Drakensberg escarpment stretches for more than 1,000 kilometres (600 miles) from theEastern Cape Province in the South, then successively forms, in order from south to north, the border betweenLesotho and theEastern Cape and the border between Lesotho andKwaZulu-Natal Province. Thereafter it forms the border between KwaZulu-Natal and theFree State, and next as the border between KwaZulu-Natal andMpumalanga Province. The escarpment winds north from there, throughMpumalanga, where it includes features such as theBlyde River Canyon,Three Rondavels, andGod's Window. It then extends farther north toHoedspruit in southeasternLimpopo where it is known as 'Klein Drakensberg' by theAfrikaner. From Hoedspruit it extends west toTzaneen, also inLimpopo Province, where it is known as theWolkbergMountains and Iron Crown Mountain. At 2,200 m (7,200 ft) above sea level, the Wolkberg is the highest elevation in Limpopo. The escarpment extends west again and atMokopane it is known as the Strydpoort Mountains.[1][2]
TheAfrikaans nameDrakensberge comes from the name the earliestDutch settlers gave to the escarpment, namelyDrakensbergen, orDragons' Mountains. The highest portion of the Great Escarpment is known inZulu asuKhahlamba and asMaloti inSotho ("Barrier of up-pointed spears").[3]
The Great Escarpment is composed of steeprift valley walls formed around a bulging of continental crust during the breakup of southernGondwana that have since eroded inland from their original positions near the southern African coast, and its entire eastern portion (see the accompanying map) constitutes the Drakensberg.[1][4][5] The Drakensberg terminate in the north near Tzaneen at about the 22° S parallel. The absence of the Great Escarpment for approximately 450 km (280 mi) to the north of Tzaneen (to reappear on the border betweenZimbabwe andMozambique in theChimanimani Mountains) is due to a failed westerly branch of the main rift that causedAntarctica to start drifting away from southern Africa during the breakup of Gondwana about 150 million years ago. The lowerLimpopo River andSave River drain into theIndian Ocean through what remains of this relict incipient rift valley, which now forms part of the South AfricanLowveld.[5]
During the past 20 million years, southern Africa has experienced massive uplifting, especially in the east, with the result that most of the plateau lies above 1,000 m (3,300 ft) despite extensive erosion. The plateau is tilted such that it is highest in the east and slopes gently downward toward the west and south. Typically, the elevation of the edge of the eastern escarpments is in excess of 2,000 m (6,600 ft). It reaches its highest point of over 3,000 m (9,800 ft) where the escarpment forms part of the international border betweenLesotho and the South African province ofKwaZulu-Natal.[1][5]
This approximate SW-NE cross section through South Africa with theCape Peninsula (withTable Mountain) on the far left, and north-easternKwaZulu-Natal on the right, is diagrammatic and only roughly to scale. It shows how theDrakensberg Escarpment is related to the major geographical features that dominate the southern and eastern parts of the country, particularly the Central Plateau, whose southwestern edge (in the diagram) is called the Roggeberg escarpment (not labelled). The major geological layers that shape this geography are indicated in different colors whose significance and origin are explained under the headings "Karoo Supergroup" and "Cape Supergroup". The 1600 m thick layer of hard, erosion-resistant basalt (lava) that accounts for the height and steepness of the Drakensberg Escarpment on the KwaZuluNatal-Lesotho border is indicated in blue. Immediately below it is theStormberg Group shown in green. The Clarence Formation with its numerous caves andSan rock paintings, forms part of this latter group.
The escarpment seen from below resembles a range of mountains. The Limpopo, Mpumalanga, and Lesotho Drakensberg have hard erosion-resistant upper surfaces and therefore have a very rugged appearance, combining steep-sided blocks and pinnacles (giving rise to the Zulu name "Barrier of up-pointed spears"). Who first gave these mountains their Afrikaans or Dutch nameDrakensberg, and why, is unknown.[3] The KwaZulu-Natal – Free State Drakensberg are composed of softer rocks and therefore have a more rounded, softer appearance from below. Generally, the top of the escarpment is almost table-top flat and smooth, even in Lesotho. The "Lesotho Mountains" are formed away from the Drakensberg escarpment by erosion gulleys which turn into deep valleys containing tributaries of theOrange River. The large number of such tributaries give theLesotho Highlands a very rugged mountainous appearance, both from the ground and from the air.
The higher parts of Drakensberg have a mildlyperiglacial environment. It is possible that recentclimate change has diminished the intensity of periglaciation.[6]
Knight and Grab mapped out the distribution of lightning strikes in the Drakensburg and discovered that lightning significantly controls the evolution of the mountain landscapes because it helps to shape the summit areas – the highest areas – with this blasting effect. Previously, angular debris was presumed to have been created by changes typical of cold, periglacial environments, such as fracturing due to frost.[7]
The geological composition of Drakensberg (escarpment wall) varies considerably along its more than 1000 km length. The Limpopo and Mpumalanga Drakensberg are capped by an erosion resistant quartzite layer that is part of the Transvaal Supergroup, which also forms theMagaliesberg to the north and northwest of Pretoria.[5] These rocks are more than 2000 million years old. South of the 26°S parallel the Drakensberg escarpment is composed ofEcca shales, which belong to theKaroo Supergroup, and they are 300 million years old.[5][8] The portion of the Drakensberg that forms the KwaZulu-Natal – Free State border is formed by slightly youngerBeaufort rocks (250 million years old) that also are part of the Karoo Supergroup.
The Ecca and Beaufort groups are composed of sedimentary rocks that are less erosion resistant than the other rocks that make up the Drakensberg escarpment. Therefore, this portion of escarpment is not so impressive as the Mpumalanga and Lesotho stretches of the Drakensberg. The Drakensberg that form the northeastern and eastern borders of Lesotho, as well as the Eastern Cape Drakensberg, are composed of a thick layer of basalt (lava) that erupted 180 million years ago.[5][8] That layer rests on the youngest of the Karoo Supergroup sediments, theClarens sandstone, which was laid down under desert conditions, about 200 million years ago.[5][8]
The highest peak isThabana Ntlenyana, at 3,482 m (11,424 ft). Other notable peaks includeMafadi (3,450 m (11,319 ft)),Makoaneng at 3,416 metres (11,207 ft),Njesuthi at 3,408 metres (11,181 ft),Champagne Castle at 3,377 metres (11,079 ft),Giant's Castle at 3,315 metres (10,876 ft),Ben Macdhui at 3,001 metres (9,846 ft), andPopple Peak at 3,331 metres (10,928 ft), all of these are in the area bordering on Lesotho, which contains an area popular for hikers,Cathedral Peak. North of Lesotho the range becomes lower and less rugged until entering Mpumalanga where the quartzite mountains of the Transvaal Drakensberg are loftier and more broken and they form the eastern rim of the Transvaal Basin, theBlyde River Canyon lying within this stretch. The geology of this section is the same as, and continuous with, that of theMagaliesberg.
Tugela Falls vicinity – Tugela River in valleyLittle Saddle
The high treeless peaks of the Drakensberg (from 2,500 m (8,200 ft) upward) have been described by theWorld Wide Fund for Nature as theDrakensberg alti-montane grasslands and woodlandsecoregion. These steep slopes are the most southerly high mountains in Africa, and being farther from the equator provide cooler habitats at lower elevations than most mountain ranges on the continent. High rainfall generates many mountain streams and rivers, including the sources of theOrange River, southern Africa's longest, and theTugela River.
These mountains also have the world's highest waterfall, theTugela Falls (Thukela Falls), which has a total drop of 947 m (3,107 ft) (Venezuela's Angel Falls is also a candidate for highest waterfall). The rivers that run from the Drakensberg are an essential resource for South Africa's economy, providing water for the industrial provinces of Mpumalanga andGauteng, which contains the city ofJohannesburg.[9] The climate is wet and cool at the high elevations, which experience snowfall in winter.
The grassy lower slopes (from 1,800 to 2,500 m (5,900 to 8,200 ft)) of the Drakensberg inEswatini, South Africa and Lesotho constitute theDrakensberg montane grasslands, woodlands, and forests ecoregion.
The mountains are rich in plant life, including a large number of species listed in the Red Data Book of threatened plants, with 119 species listed as globally endangered and "of the 2 153 plant species in the park, a remarkable 98 are endemic or near-endemic".[10]
Theflora of the high alti-montane grasslands is mainlytussock grass, creeping plants, and small shrubs such asericas. These include the rare Spiral Aloe(Aloe polyphylla), which as its name suggests, has leaves with a spiral shape.
Meanwhile, thelower slopes are mainly grassland, but are also home toconifers, which are rare in Africa, the species of conifer found in the Drakensberg belong to the genusPodocarpus. The grassland is of interest as it contains a great number ofendemic plants. Grasses found here include oat grassMonocymbium ceresiiforme,Diheteropogon filifolius,Sporobolus centrifugus, caterpillar grass(Harpochloa falx),Cymbopogon dieterlenii, andEulalia villosa.
In the highest part of Drakensberg the composition of the flora is independent onslope aspect (direction) and varies, depending on the hardness of the rockclasts. This hardness is related toweathering and is variable even within a singlelandform.[6]
The Drakensberg area is "home to 299 recorded bird species"' making up "37% of all non-marine avian species in southern Africa".[10] There are 24 species of snakes in the Drakensberg, two of which are highly venomous.[11]
The lower slopes of the Drakensberg support much wildlife, perhaps most importantly the rare southernwhite rhinoceros (which was nurtured here when facing extinction) and theblack wildebeest (Connochaetes gnou, which as of 2011[update] only thrives in protected areas and game reserves). The area is home to large herds of grazing fauna and antelopes such aseland(Taurotragus oryx),reedbuck(Redunca arundinum),mountain reedbuck(Redunca fulvorufula),grey rhebok(Pelea capreolus), and even someoribi(Ourebia ourebi).Chacma baboons also are present. Endemic species include a large number ofchameleons and other reptiles. There is one endemic frog, the forest rain frog(Breviceps sylvestris), and four more species that are found mainly in these mountains; long-toed tree frog(Leptopelis xenodactylus), plaintive rain frog(Breviceps maculatus), rough rain frog(Breviceps verrucosus), and Poynton's caco(Cacosternum poyntoni).
A view of the Mpumalanga Drakensberg portion of theGreat Escarpment, fromGod's Window, nearGraskop, looking south. The hard erosion resistant layer that forms the upper edge of the escarpment here consists of flat lying quartzite belonging to the Black Reef Formation, which also forms theMagaliesberg mountains near Pretoria.[5][14]
The grassland of thelower slopes has been greatly affected by agriculture, however, especially byovergrazing. Nearly all of the original grassland and forest has disappeared and more protection is needed, although theGiant's Castle reserve is a haven for theeland and also is a breeding ground for thebearded vulture. 5.81% of the Drakensberg montane grasslands, woodlands and forests ecoregion is in protected areas. These includeKruger National Park,Mountain Zebra National Park, Golden Gate Highlands National Park,Camdeboo National Park, Sehlabathebe National Park, and Tsehlanyane National Park.[16]
San rock painting of an eland in aClarens Formation cave in the UKhahlamba Drakensberg Park ofKwaZulu-Natal close to the Lesotho border
There are numerous caves in the easily eroded sandstone ofClarens Formation, the layer below the thick, hard basalt layer on the KwaZulu Natal-Lesotho border. Many of these caves havepaintings by theSan (Bushmen). This portion of the Drakensberg has between 35,000 and 40,000 works ofSan rock art,[10][18] and is the largest collection of such parietal work in the world.
Some 20,000 individual rock paintings have been recorded at 500 different caves and overhanging sites between the Drakensberg Royal Natal National Park and Bushman's Nek.[18] Due to the materials used in their production, these paintings are difficult to date, but there is anthropological evidence, including many hunting implements, that the San people existed in the Drakensberg at least 40,000 years ago, and possibly more than 100,000 years ago. According to mountainsides.co.za, "[i]n Nd edema Gorge in the Central Ginsberg 3,900 paintings have been recorded at 17 sites. One of them, Sebaayeni Cave, contains 1,146 individual paintings."[19] The website, south Africa.info, indicates that although "the oldest painting on a rock shelter wall in the Ginsberg dates back about 2400 years... paint chips at least a thousand years older have also been found."[10] The site also indicates that "[t]he rock art of the Drakensberg is the largest and most concentrated group of rock paintings in Africa south of the Sahara, and is outstanding both in quality and diversity of subject."[10]
Rosen, Deborah; Lewis, Colin; Illgner, Peter (1999). "Palaeoclimatic And Archaeological Implications of Organic- Rich Sediments at Tifftidell Ski Resort, Near Rhodes, Eastern Cape Province, South Africa".Transactions of the Royal Society of South Africa.54 (2):311–321.doi:10.1080/00359199909520630.
.jpg)
