It is important to know that niger delta is situated in the gulf of guinea and extends throughout the niger delta province as defined by klett and others 1997. Otu field is an onshore field located in the western part of the niger delta, nigeria and lies between latitudes 5n and 6n and longitudes 5e and 6e fig. The niger delta basin is situated on the continental margin of the gulf of guinea between latitude 30 and 60n and longitude 50 and 80e. A case study of well in offshore depobelt, niger delta, nigeria. Niger delta by 1 while 3 reported a geothermal gradient range of 1.
Pdf 3d seismic interpretation and structural analysis. Regional structural elements and depobelts of the niger delta. A comparative model approach to pore pressure prediction. A mathematical correlation of porosity and permeability. The results of the sand analysis and correlation show that at obua023, sand a is located between depths 10875 10940ft true vertical depth subsea sstvd. Map of the niger delta depobelts showing the location of beta field in the northern depobe lt modified from ejedavwe et al. The niger delta is situated on the continental margins of the gulf of guinea and extends throughout the niger delta province as defined by klett et. Assessment of hydrocarbon potential in owem field in niger. Crossplots for cumulative number of oil and gas fields in the niger delta province 11 figure 6.
Petrophysical characteristics of coastal swamp depobelt reservoir in the niger delta using welllog data dieokuma tamunosiki 1, gu han ming1 and liping wang1, etim d. Previous studies have investigated the concept of sequence stratigraphy in relation to hydrocarbon exploration in different parts of the niger delta. Modeling hydrocarbon generation potentials of eocene. Successive phases of delta development, referred to as depobelts, may be distinguished. The studied area is located within the niger delta sedimentary basin figure 1. The niger delta is situated in the gulf of guinea and extends throughout the niger delta province. Sequence stratigraphy, variable sedimentations, sea level. Subsidence of the african continental margin and cooling of the newly. Hydrocarbons have been located in all of the depobelts of the niger delta, in good quality sandstone reservoirs belonging to the. Sequences, systems tracts and stratigraphic surfaces defined in relation to the baselevel and the transgressiveregressive curves 15 prograding and aggrading and terminated at the basal surface of forced regression. These depobelts are regarded as one of the largest regressive deltas. Oil and gas in the niger delta are primarily produced from.
Obua fieldis locatedwithin southwest ofthe central swamp depobelt of niger delta basin fig. Modeling hydrocarbon generation potentials of eocene source. A sketch showing the studied area and different depobelts in niger delta. Depositional environments of sambis oil field reservoir sands, niger delta, nigeria 1oyanyan, r. The niger delta is situated in the gulf of guinea and extends throughout the niger delta province as defined by klett and others 1997. Hydrocarbon play assessment of xfield in an onshore niger. The analysis was based on a combination of data sets including logs of six wells to describe lithic variations of the agbada formation within the ab field. Uko2 and warmate tamunonengiyeofori2 1 department of geophysics and geomatics, china university of geosciences, 388 lumo road, wuhan city, hubei province 430074, p. Static reservoir modeling using well log and 3d seismic data. These depobelts form one of the largest regressive deltas in. From eocene to the present, there was progradation of the delta towards the southwest, which resulted in formation of the depobelts that represent the most active portion of the delta. Schematic diagram showing the development of growthfault bounded depobelts 14.
Midlower miocene agbada sedimentary intercalations of ab field in the coastal swamp depobelt, western nigerdelta, were evaluated to determine their sequence stratigraphic character. Growth fault history analysis of an oil field, niger delta. These depobelts form one of the largest regressive deltas in the world with an area of some 300,000 km 2 8, and a sediment thickness of over 10 km in the basin depocenter. Previous studies have investigated the concept of s equence stratigraphy in relation to hydrocarbon exploration in different parts of the niger delta. Apr 30, 2009 the niger delta started to evolve in early tertiary times when clastic river input increased doust and omatsola, 1989. Introduction the niger delta is ranked among the worlds major hydrocarbon provinces in the world. Reservoir characterization in o field in the niger delta. Although the modern niger delta formed in the early tertiary, sediments began to accumulate in this region during. Such depobelts changed position over time as local accommodation was filled and the locus of deposition shifted basinward doust and omatsola, 1990. The basin is made up of onshore fields as well as continental shelf and deep offshore environments.
The drainage density is very high and has given rise to an intricate drainage texture. Niger delta is bounded in the north by older cretaceous tectonic elements among which are the anambra basin, abakaliki uplift and afikpo syncline. Northern delta, greater ughelli, central swamp, coastal swamp and offshore depobelt fig. An estimate of oil window in nigeria niger delta basin. The evolution of geological tectonics in the niger delta. These cycles depobelts are 3060 kilometers wide, prograded southwestward 250 kilometers over oceanic crust into the gulf of guinea stacher, 1995, and are defined by. Petroleum geology of the niger delta geological society, london.
Schematic section from the niger delta continental sloperise 12 figure 7. Depositional environments of sambis oil field reservoir. Sequence stratigraphic study of b24 well northern depobelt. In obua024, sand a is at a depth range of 10940 11015ft sstvd.
The niger delta basin, also referred to as the niger delta province, is an extensional rift basin located in the niger delta and the gulf of guinea on the passive continental margin near the western coast of nigeria with suspected or proven access to cameroon, equatorial guinea and sao tome and principe. These cycles depobelts are 3060 kilometers wide, prograde southwestward 250 kilometers over oceanic crust into the gulf of guinea stacher, 1995, and are defined by synsedimentary faulting that occurred in response to variable rates of subsidence 3 and sediment. The akata formation is the hydrocarbon source rock in niger delta. Agbada formation that is made up of mostly sandstone and unconsolidated sands is the hydrocar bon host in the niger delta basin. The fundamental causative event for the origin of the niger delta basin was the breakup of the gondwana supercontinent. Reservoir studies using seismic attributes and well log. Location and geological setting of the niger delta the niger delta is located in the gulf of guinea, central west africa, at the southern culmination of the benne trough8. The encountered assemblages indicated a preponderance of forms belonging to terrestrial origin which include. Structural and stratigraphic mapping of delta field. Deposition of the three formations occurred in each of the five off lapping siliciclastics sedimentation cycles that comprise the niger delta.
Subsurface mapping and reservoir evaluation of enena field. Stratigraphy and sedimentology of the niger delta sciendo. The study area for this paper lies in the northern delta depobelt considered the oldest and as one of the productive hydrocarbon depobelt in the niger delta basin. The tertiary niger delta covers an area of about 75,000 sq km9.
Geology of the study area the stratigraphic sequence of the niger delta comprises three broad lithostratigraphic units, namely, a conti. Delta field, niger delta, integration, stratigraphic mapping, structural interpretation, well logs. Niger delta cenozoic chronostratigraphic chart source. Niger delta sedimentary basin is a large arcuate delta of the destructive dominated wave type that has been explored for oil and gas and exploited since 1958. Seismic sequence stratigraphy and structural trends of the. Study location, geologic setting and clay mineralogy representative wells of gbaran, santa barbara, kolo creek, elepa and korokoro fields respectively. The morphology of the niger delta can be subdivided into an early stage. The niger delta basin is situated on the continental margin of the gulf of guinea in equatorial west africa between latitude 30n and 60n and longitude 50e and 80e reijers 1996. Northern delta, greater ughelli, central swamp, and coastal swamp and offshore depobelts. Niger delta, biostratigraphy, sedimentology, megasequences, cycles 1. The growth faults are generated by rapid sedimentation and.
Niger delta akataagbada petroleum system of9950h, chapter a. This was based on seismic and well velocity data within common. Some of the reservoirs having comparable depobelts had been analysed together and in the process, two 2 depobelts have been analysed. Niger delta province, nigeria, cameroon, and equatorial guinea, africa. The benin formation is the upper alluvial coastal plain depositional environment of the niger delta complex. Niger delta depobelts and structures various integrated studies have shown that several depobelts exist in the niger delta basin which are separated by major synsedimentary fault zones that occurred in response to variable rates of subsidence and sediment supply doust and omatsola, 1990. Pdf sequence stratigraphy and hydrocarbon distribution in parts. The benue trough had been formed as part of the widely distributed african rift population which originated some 140 million years ago burke, 1996.
Pdf 3d seismic interpretation and structural analysis of. The first coarse clastic deposits have been dated on the basis of microfloral units evamy et al. From the eocene to the present, the delta has prograded southwestward, forming depobelts that represent the most active portion of the delta at each stage of its development 2,6. Static reservoir modeling using well log and 3d seismic. In the wetland niger delta, the niger river, the worlds seventh longest river 4120km long, bifurcates into the nun and forcados rivers whose distributary pattern is actually responsible for the origin of the reticulate drainage pattern that characterizes the niger delta proper.
Onshore niger delta, nigeria southwestward, forming depobelts that represent the most active portion of the delta at each stage of its development 7. This portion of the system has a total surface area of 7675 km2 and contains about 3 billion bbl of mostly light waxy crude oil and over 7 trillion scf of gas. Evaluation of hydrocarbon volume in trh field, onshore. Each of the reservoirs was analysed by plotting porosity to permeability and outliers. Integrated reservoir quality study of deepwater clastic. The niger delta is situated in the gulf of guinea figure 2 and extends throughout the niger delta province. It is one of the largest regressive deltas in the world10. The niger delta covers a 70,000 square kilometer area within the gulf of guinea, west africa. Petrophysical evaluation of otebe field, onshore niger. Today, the delta is covered with a dense grid of 2d and 3d seismic data and it has been penetrated by more than 5,000 wells. Characteristic trace fossils from miocene brackish water. Weber 5 suggested that the basin which facilitated and controlled the formation of the present niger delta was developed by rift faulting during the precambrian. Oil and gas in the niger delta are primarily produced from sandstones and unconsolidated sands mainly in the agbada formation. Biostratigraphy of the upper tertiary western offshore, niger delta, nigeria oloto, i.
It is the most prolific and economic basin in africa. Along with the growth faults, rollover anticlines, shale ridges, and shale diapirs exist in the basin and can be seen in the schematic structural profile of the niger delta. Figure 2 is the geology map of niger delta basin, showing regional structural elements and depobelts of the niger delta basin. Greater ughelli depobelt and northern delta depobelt.
Petters, 1984, resulting in the agbada, elekelewu, soku and afam channels figs 2, 4b. Petrophysical characteristics of coastal swamp depobelt. From the eocene to the present, the delta has prograded southwestward, forming depobelts that represent the most active portion of the delta at each stage or its development 12. Location map of niger delta showing the study area and the inset of map of nigeria the benin formation which is the topmost section of the niger deltaconsists predominantly continental sands. Investigating the subsurface pressure regime of adafield. From the eocene to the present, the delta has prograded southwest ward, forming depobelts that represent the most active portion of the delta. Northern delta depobelt portion of the akataagbada. The study area is in the greater ughelli depobelt of the niger delta basin of nigeria. This is located within the niger delta basin and sits in 12 feet of water.
Anisotropy and empirical relations for the estimation of. Map of the niger delta depobelts showing the location of b24 well modified after stacher, 1995 several studies have been carried out in relation to the sequence stratigraphy of different wells in the niger delta basin. The delta field is located on the dominantly extensional proximal margin of a major collapse structure. Structural and stratigraphic mapping of delta field, agbada. The niger delta basin the cenozoic niger delta is situated at the intersection of the benue trough and the south atlantic ocean where a triple junction developed during the separation of the continents of south america and africa in the late jurassic whiteman, 1982. Stratigraphy and sedimentology of the niger delta 9 depobelts became active. The niger delta is ranked among the worlds major hydrocarbon provinces in the world.
This basin is very complex, and it carries high economic value as it contains a very productive. Paul bellingham, chris connors, richard haworth, barbara radovich and al danforth ion geophysical regional, deeppenetrating 2d seismic data is imaging new petroleum potential in this prolific province. During the following decades the temperature measurements in boreholes were an important element of the hydrocarbon prospecting. Petrophysical evaluation of uzek well using well log and core. The delta is a coarsening upward regressive sequence of tertiary clastics that prograded over a passive continental margin sequence of mainly cretaceous sediments. It located in equatorial west africa, between latitude 3. Since its formation, the delta has prograded southwestwards forming depobelts which are the active portion of the niger delta. A mathematical correlation of porosity and permeability for. From eocene to the present, the delta has prograded southwestward, forming depobelts that represent the most active portion of the delta at each stage of its development 9. Generally the delta prograded over the subsidizing continentaloceanic lithospheric transition zone, and during the oligocene spread onto oceanic crust of the gulf of guinea adesida et al. The entire delta is composed of three major structural formations.
Reservoir studies using seismic attributes and well log and. Deposition of the three formations occurred in each of the five offlapping siliciclastic sedimentation cycles that comprise the niger delta. Pdf origin and occurrence of crude oil in the niger. Stratigraphy and sedimentology of the niger delta geologos. Sequence stratigraphy of akos field in the coastal swamp. Sequence stratigraphy of akos field in the coastal swamp depobelt of the niger delta tope s alege department of earth sciences, kogi state university, anyigba, nigeria abstract welllog sequence stratigraphy has been carried out in the akos field aimed at studying its stratigraphic framework. Geologic map of the niger delta showing depobelts and structural elements. Formations in niger delta area, nigeria short and stauble, 1967. During the cenozoic, until the middle miocene, the niger delta grew through pulses of sedimentation over an oceanwarddipping continental basement into the gulf of guinea. It extends from the west niger delta across the entire niger delta area and to the south. Oct 15, 2016 the niger delta basin is divided into five depobelts namely. Location of gx1 and gx2 well within the niger delta depobelts. Benin formation is underlain by the paralicagbada formation which is the major petroleum bearing unit in niger delta.
Stratigraphy and sedimentology of the niger delta in. From the eocene to the present, the delta has prograded southwestward, forming depobelts that represent the most active portion of the delta at each stage of its development doust and omatsola, 1990. The niger delta petroleum system usgs publications repository. Abstract the niger delta is a prolific oil province within the west african subcontinent. In the eastern delta, sedimentation was interrupted by cuttingandfilling events burke, 1972. Keywords oil generation eocene niger delta source rock northern delta depobelt introduction the niger delta basin, located on the western edge of the african continent and southern part of nigeria, covers an area of 75,000 km2 and consists of 900012,000 m of. The delta field is located offshore from nigeria on oil mining leases oml 49 and 95. During the pliocene, catastrophic gravity events, possibly related to. Niger delta province, nigeria, cameroon, and equatorial guinea, africa by michele l. From the eocene to the present, the delta has prograded southwest ward, forming depobelts that represent the most active portion of the delta at each.
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