describe some of its marine geological aspects?
A zone 50 m wide extending from the island of Ceylon and the Coromandel coast to the head of the bay. It is bounded by the 100 fathom line of sea bottom and some 50 m. beyond this lies the 500-fathom limit.
Bay of Bengal
A zone 50 m wide extending from the island of Ceylon and the Coromandel coast to the head of the bay, and thence southwards through a strip embracing the Andaman and Nicobar islands, is bounded by the 100 fathom line of sea bottom; some 50 m. beyond this lies the 500-fathom limit. 
where do cyclones occur in the southern hemisphere They generally form on a regular basis between the African coast and the middle of the South Pacific. what is "tropical cyclone basins"? They are divided into seven basins. These include the "North Atlantic Ocean", the eastern and western parts of the "North Pacific Ocean", the southwestern “Pacific Ocean", the southwestern and southeastern "Indian Ocean", and the northern "Indian Ocean" i.e. "Arabian Sea" and "Bay of Bengal". from where did the last mention region get its name? It gets its name from the historical Bengal region. how is the water quality of the bay? The water is polluted with sewage-borne pathogens and organic load; solid waste/marine litter; increasing nutrient inputs; oil pollution; persistent organic pollutants and persistent toxic substances; sedimentation; and heavy metals. describe in few words about its climate? They face severe cyclones. what is the reason behind the degradation of marine habitats? Lack of coastal development plans, increasing trade in products from coastal habitats, coastal development and industrialization, ineffective marine protected areas and lack of enforcement are some of the causes.
wiki:11576529
Bay of Bengal [SEP] Marine geology
A zone 50 m wide extending from the island of Ceylon and the Coromandel coast to the head of the bay, and thence southwards through a strip embracing the Andaman and Nicobar islands, is bounded by the 100 fathom line of sea bottom; some 50 m. beyond this lies the 500-fathom limit. Opposite the mouth of the Ganges, however, the intervals between these depths are very much extended by deltaic influence. Swatch of No Ground is a 14 km-wide deep sea canyon of the Bay of Bengal. The deepest recorded area of this valley is about 1340 m. The submarine canyon is part of the Bengal Fan, the largest submarine fan in the world.