Bengal delta
The Ganges-Brahmaputra Delta (also known as the Brahmaputra Delta, the Sunderbans Delta, or the Bengal Delta) in Bangladesh and in West Bengal (India) is a river delta in the Bengal region of the Indian subcontinent, consisting of Bangladesh and the Indian state of West Bengal. It is the world's largest delta, and empties into the Bay of Bengal. It is also one of the most fertile regions in the world, thus earning the nickname The Green Delta. The delta stretches from the Hooghly River on the west to the Meghna River on the east. It is approximately 354 km (220 mi) across at the Bay of Bengal.Kolkata (formerly Calcutta) and Haldia in India and Mongla and Chittagong in Bangladesh are the principal seaports of the delta.
A number of large rivers flow through the Brahmaputra Delta, including the Padma (main distributary of the Ganges) and the Jamuna (main distributary of the Brahmaputra), which merge and then join the Meghna before entering the sea.
The Ganges Delta has the shape of a triangle, and is considered to be an "arcuate" delta (arc-shaped). It covers more than 105,000 km2 (41,000 sq mi), and although the delta lies mostly in Bangladesh and India, rivers from Bhutan, Tibet, India, and Nepal drain into it from the north. Approximately two-thirds of the delta is in Bangladesh. Most of the delta is composed of alluvial soils made up by small sediment particles that finally settle down as river currents slow down in the estuary. Rivers carry these fine particles with them, even from their sources at glaciers as fluvio-glacial. Red and red-yellow laterite soils are found as one heads farther east. The soil has large amounts of minerals and nutrients, which is good for agriculture.
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