The Etosha Pan has been a source of fascination for geologists for many years and a large amount of research into the origins of this amazing phenomenon has been conducted.
Gondwanaland was situated at the South Pole 300 million years ago and covered in ice. The area now occupied by the Etosha pan was submerged under a massive glacier, several kilometres thick. For about 20 million years the oppressive weight of this glacier further compressed the pan, leaving a huge depression when the super-continent’s northward drift caused the ice to melt.
Gradually, Gondwanaland began to break up into the continents of Africa, South America, India and Antarctica, leaving the Etosha and Okavango basins cocooned between the edges of the African continental margins.
Over the next several million years, Etosha underwent intermittent periods of flooding and drought. Evidence suggests that between five and seven million years ago, the pan was filled with water, forming a massive lake which would have been the third largest in the world today. Fossils of fish and sitatunga antelope imply that Etosha may still have been under water as recently as 5000 years ago.
Continuing continental drift, upheaval and erosion caused the pan to decrease in size from its original 70 000 km² to the present 4 590 km². In addition, the water sources which fed the lake were gradually diverted toward the Atlantic Ocean. With no major influx of water, the lake continued to shrink and eventually vanished altogether.
Nowadays, the pan only fills during the rainy season and with no natural outlet, all this water is lost to evaporation, leaving behind the salty mineral deposits which form the dazzling white winter landscape of Etosha. The only plants which can survive this saline habitat are the salt bush and Craspedarhachis africana, another salt-loving shrub.
There are a few sources which still drain into the pan intermittently during the rainy season, the Ekuma and Oshigambo inlets in the north and the Omuramba Owambo in the east. These are tiny channels which, together with the annual rainfall, are unable to fill the pan to a depth of more than 15 centimetres. In present times, the deepest recorded water level at Etosha was 50 centimetres during the 1930’s.
An ancient watercourse remains in the Springbokfontein-Okerfontein area which can fill to a depth of 60 centimetres in a good year. This area is much favoured by the Greater and Lesser Flamingos during the summertime as the narrow watercourse protects their eggs from marauding predators such as jackal.
Several contact and artesian springs, like the ones found at Okerfontein and Klein Namutoni, are present in the vicinity of the pan. These attract large numbers of wild animals during the dry season when water sources are scarce. The pan is also an important source of minerals for these animals that lick the salt from the surface of the pan.
Strong easterly winds prevail during the dry season, creating spectacular dust storms and spreading the life-giving salt far and wide. Satellite images show instances of dust clouds extending as far west as the Atlantic Ocean. At times these dust clouds are so dense that visibility is reduced to only a few hundred metres.
The most obvious feature of Etosha is the salt pan itself. Covering an area of approximately 5 000 square kilometres, the pan is about 130 kilometres long and 50 kilometres wide in places. The extremely salty composition of the pan severely limits the life forms that can survive here permanently, but it springs to life during the rainy season when flamingos, pelicans and other birds flock to its shallow shores.
A second outstanding geographical feature of Etosha is the dolomite hills to the south of Okakuejo and the Helio hills near Halali. These are thought to be left over from the dolomites and limestone slabs which tilted upward from the sea shelf during the formation of Gondwanaland. The oldest fossils in the world, called stromatolites, have been found here.
One of these outcrops is referred to by locals as Ondundozonananandana. This means “the place where a young boy herding cattle went and never returned”. Thinking that this must surely be the work of leopards, Europeans later named the place Leopard Hills. The Halali area features a dolomite hill within the camp as well as the nearby Twee Koppies, and the dolomite hills in Western Etosha is the only place in the park frequented by Mountain zebra.