Local source rock palynology of ANL -1 and E -12 wells sediments offshore Niger delta, Nigeria: Implication for hydrocarbon prospectivity
Abstract
Local source rock potential of ANL-1 and E-12 well sediments in offshore, NigerDelta have been evaluated based on organic matter maturation studies to provideleads for hydrocarbon exploration. The studied wells display diverse palynoflora atdifferent stratigraphic levels and indicate variable palaeoecological conditions of thedepositional environment. E -12 well sediments are composed of the lower Agbadaformation and are thermally mature (TAI 2.8; 1932 -2238 m and TAI 3.0; 2410 –2603 m ), showing top of oil window and intense generation of liquid hydrocarbonwhile the upper part ( TAI 1.7; 1230 – 1770 m) and the overlying Benin formation(TAI 1.5; 681 – 1176 m) are thermally immature. Immature (TAI 1.3) thermal faciesis determined for depths: 216 – 1773 m (Benin formation) in the ANL -1 well, whilemature (TAI 2.7) thermal facies is determined for depths: 1863 – 2556 m and TAI3.0 is determined for depths 2583 – 3663m (Agbada formation) in the ANL – 1 well.Shale of the lower and upper part of Agbada formation in the ANL – 1 and E – 12indicates an optimum maturation level of a good hydrocarbon source rock potential.
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