Petroleum industry in Nigeria to transport the crude oil. Also because of the lack of highly productive fields, money from the jointly operated (with the federal government) companies is constantly directed towards petroleum exploration and production. Nigeria's petroleum is classified mostly as "light" and "sweet", as the oil is largely free of sulphur. Nigeria is the largest producer of sweet oil in OPEC. This sweet oil is similar in composition to petroleum extracted from the North Sea. This crude oil is known as "Bonny light". Names of other Nigerian crudes, all of which are named according to export terminal, are Qua Ibo, Escravos blend,
Enclaves of Forcados and Badjibo families and servants. The lease was for a renewable period of thirty years in each case, and included conditions such as a requirement to enclose the area and to forbid retail trading. The annual rent was set at one franc per year. The enclaves were mentioned in French textbooks in 1926 and described as unoccupied in 1929. The leases were not renewed at the end of the initial thirty year period. The name 'Forcados' (meaning 'forked') was given to the area by the first Portuguese slave traders to explore the Niger delta in the current Bayelsa State. The leased area