The Ganges-Brahmaputra Delta, also known as the Brahmaputra Delta, the Sunderbans Delta, or the Bengal Delta, 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. Rivers from Bhutan, Tibet, India, and Nepal drain into it from the Himalayas in the North. 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.