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Chad Basin: Nigeria Extent

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The Chad basin is located in West Africa. It's region is largely characterized by Lake Chad whcih serves irrigaton purposes to alot of the indigenes living in that area. The Nigeria extent of the Chad basin makes up about 10% of the entire area. [1] The Republic of Chad is currently engaged in oil production from this basin while the extent occupied by Nigeria is currently under intensive exploratory activities by the NNPC.[2]

Area extent of Chad Basin

Geology

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On a macro scale the formation of the Chad basin and other sub basins such as Benue trough of Nigeria can all be attributed to the large rifting activities of the early Cretaceous[3]. The West and Central African rift system can be identified from Mali to Kenya which are also related to the coastal rift basins from Cameroon to Angola. The initial formation of the Chad basin was created from a failed triple-junction rifting activity that took place right before the separation of Africa and South America.[4]

It is believed that most of the formation underlying this section is primarily composed of sedimentary rocks (inter layers of nonmarine and marine sediments[5]). Rift related activities are believed to have taken place late in the Cretaceous and contribute to the geological scheme of the NE Nigeria extent of the Chad basin[1]. This tensional deformation that occured contributes to the graben and symmetric folding system structure in the Chad basin, which is a common stratigraphic profile for hydrocarbon storage.

Tension forces from rifting creating graben

Stratigraphic profile of Chad Basin: Nigeria Extent

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Age Formation Lithology Hydrocarbon results
Pliocene/Pleistocene Chad formation Clay/sand
Palaeocene Kerri Kerri Formation Coarse sandstones
Maastrichtian Gombe sandstone Shale/sandstone/siltstone HC present
Turonian-Santonian Fika shale formation Blue-black shales Source rock at low stage of maturity
Turonian Gongila formation Sandstones/shales Poor in HC content
Cenomanian Bima formation sandstones Oil/gas bearing with mature oil window

(Adapted from Carter et al., 1963, Olugbemiro et al.)

Production from the Chad Basin

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From a history standpoint exploration in Chad began in the early 1970’s but was halted due to the outbreak of the civil war in 1979. It was until the late 1980’s that exploration began again. According to data provided by the 2012 BP Statistical Energy Survey, Chad had proved reserves of 1.5MMbbl of oil as of 2011 and its daily production of about 113.6Mbbl of oil[6]. Another important thing to note about Chad oil production is that it is a land locked country so a lot of its export pipelines are co-owned and pass through neighbouring countries such as Cameroon to an FPSO.

  1. ^ a b Avbovbo; Ayoola. "Depositional and Structural Styles in Chad Basin of Northeastern Nigeria". AAPG Bulletin. 70: 1787–1798.
  2. ^ NNPC. "NNPC Intensifies Oil Search in Chad Basin > NNPC". www.nnpcgroup.com. Retrieved 2016-10-31.
  3. ^ Fairhead. "Geophysical controls on sedimention within the African rift sysems". Geological Society of London Special Publication: 19–27.
  4. ^ Burke, K (1972). Geological history of the Benue valley and adjacent areas. pp. 187–205.
  5. ^ Reyre, D. "Petroleum characteristics and geological evolution of a passive margin. Example of the Lower Congo-Babon basin". Bulletin des Centres de Recherches Exploration Production Elf-Aquitaine. 8: 303–332.
  6. ^ "Oil in Chad, Chadian Petroleum, ExxonMobil Esso Investment in Chad, Chad Cameroon Pipeline Project". www.chadnow.com. Retrieved 2016-11-14.