River delta The Okavango Delta in Botswana is one example. The generic term "mega delta" can be used to describe very large Asian river deltas, such as the Yangtze, Pearl, Red, Mekong, Irrawaddy, Ganges-Brahmaputra, and Indus. The formation of a delta is complicated, multiple, and cross-cutting over time, but in a simple delta three main types of bedding may be distinguished: the bottomset beds, foreset/frontset beds, and topset beds. This three part structure may be seen in small scale by crossbedding. The Ganges/Brahmaputra combination delta, which spans most of Bangladesh and empties into the Bay of Bengal, is the world's largest delta.
Indus River Delta fan. Memon reports that the area of mangrove forests was 263,000 hectares in 1977 and in 1990. Both agree that they were sixth-largest mangrove forests in the world. Previously there had been eight species of mangroves, although only four now remain: "Aegiceras corniculatum", "Avicennia marina", "Ceriops tagal", and "Rhizophora mucronata". Among these "Avicennia marina" constitutes 99% of the mangrove population. As of 2007, the mangroves of the Indus delta are the largest desert climate mangrove forests in the world. "Arthrocnemum macrostachyum" is also found growing in the delta. The natural flow of water and fertile sediments from Indus river into