Tuesday, September 16, 2014

Formation and Tectonics of the Okavango Delta.
     The Okavango Delta is one of the most peculiar places on earth. The delta is 18,000 square kilometers of waterways, reed beds and oasis forests in the middle of the desert. The Okavango, instead of emptying into the ocean as most deltas do, empties itself into the largest continuous stretch of sand in the world, the Kalahari Desert. This unique clashing of seemingly opposite worlds creates one of the most beautiful locations on earth as well as a thriving epicenter for African wildlife. But the secret to this mysterious desert oasis is not found on the surface but much deeper in the faults and pulling apart of tectonic plates which effect the surface here in mighty ways. It may shock you too learn that the Delta has, on average, one significant earth quake per day. Although never felt at the surface this activity alludes to the great forces that created this natural wonder.

     The waters that will eventually become the Delta originate in the Angola Highlands in the Cubango River. As it flows southeast into Namibia it becomes the Kavango River. 1000 miles later as it enters Botswana it becomes the Okavango River. A series of fault lines then cause the river to split into its fan-like form. The first is the Gomare fault. At this point the Okavango river splits into many different waterways. It then flows over many other parallel faults until it is finally stopped by the Kunyere and Thamalakane faults. These faults act to block the water from progressing into the desert and so the water, as if by magic, comes to an abrupt halt. 

     This faulting can be seen as a continuance of the African Rift Valley found to the northeast. Here the Nubian and Somali plates are pulling Africa apart. The faulting that has formed the Okavango owes its origin to this rift system that is so far away.


Sources:
http://www.nytimes.com/books/first/e/eldredge-life.html

http://www.eyesonafrica.net/african-safari-botswana/okavango-info.htm

http://education.nationalgeographic.com/education/encyclopedia/rift-valley/?ar_a=1