The structural framework and stratigraphy of the Ariki Field in the Western Shallow Offshore Depo... more The structural framework and stratigraphy of the Ariki Field in the Western Shallow Offshore Depobelt, Niger Delta Basin, Nigeria are interpreted using well logs and 3-D seismic data, and the control of rift on hydrocarbon accumulation is analyzed. Five maximum flooding surfaces and five sequence boundaries are identified in the major reservoir succession of Agbada Formation in the field; and the structural framework of the field is controlled by the major growth faults, minor faults and rollover anticlines formed by synsedimentary tectonic movements. There are a total of seven faults identified across the field, including three major faults and four minor faults. On the western flank of the field, graben and horst-like structures were bounded by minor faults. Fault throw analysis shows that below 1800 ms, the major faults with large fault throws act as hydrocarbon migration pathways, while above 1 800 ms, faults with small throws act as seals of hydrocarbon traps. There are four-way dip rollover anticlines and three-way downdip traps created by the minor faults. Six other prospective traps (drilling targets) were identified, which have promising oil accumulation potential.
As Nigerian operations expand into more
challenging and costly operating environments of deepfron... more As Nigerian operations expand into more challenging and costly operating environments of deepfrontiers, there is need for critical access to sound stratigraphic, depositional and reservoir facies models. The extraction of facies types from geometric insights and pattern recognition using predominantly 3D seismic data is a rapidly evolving discipline that facilitates the development of reservoir prediction models linked to significant plays. Play based exploration approach such as this provides the critical link between regional observations and prospect generation. In this study a regional dataset which comprised of a merged 3D seismic volume, well logs, biostratigraphic, biofacies, paleobathymetry and core data from Eastern Niger Delta was interpreted. Results clearly show the overall structural, stratigraphic and architectural styles within the region to ensure that successes achieved in the past can be repeated and also significant advances made to ensure future exploration success. An added outcome is a low-risk exploration workflow that is capable of correctly predicting reservoir rocks to be encountered in a new play and prospect. Three plays have been identified from this study: (1) shelf edge deltas, (2) pinch-out play and (3) hanging wall play. Each play displays a unique morphology, seismic expression, structural configuration, migration pathway, seal integrity and reservoir dispersal pattern. These prediction models provide play based exploration targets for areas with similar depositional settings. The successful application of this technique serve to encourage exploration in the Niger Delta Basin by adopting strategies where seismic stratigraphy will be the most likely means to provide drilling targets to more independent operators. Keywords: Seismic stratigraphy Structural configuration Pattern recognition Petroleum plays
Abstract As Nigerian operations expand into more
challenging and costly operating environments of... more Abstract As Nigerian operations expand into more challenging and costly operating environments of deep frontiers, there is need for critical access to sound stratigraphic, depositional and reservoir facies models. The extraction of facies types from geometric insights and pattern recognition using predominantly 3D seismic data is a rapidly evolving discipline that facilitates the development of reservoir prediction models linked to significant plays. Play based exploration approach such as this provides the critical link between regional observations and prospect generation. In this study a regional dataset which comprised of a merged 3D seismic volume, well logs, biostratigraphic, biofacies, paleobathymetry and core data from Eastern Niger Delta was interpreted. Results clearly show the overall structural, stratigraphic and architectural styles within the region to ensure that successes achieved in the past can be repeated and also significant advances made to ensure future exploration success. An added outcome is a low-risk exploration workflow that is capable of correctly predicting reservoir rocks to be encountered in a new play and prospect. Three plays have been identified from this study: (1) shelf edge deltas, (2) pinch-out play and (3) hanging wall play. Each play displays a unique morphology, seismic expression, structural configuration, migration pathway, seal integrity and reservoir dispersal pattern. These prediction models provide play based exploration targets for areas with similar depositional settings. The successful application of this technique serve to encourage exploration in the Niger Delta Basin by adopting strategies where seismic stratigraphy will be the most likely means to provide drilling targets to more independent operators. Keywords Seismic stratigraphy Structural configuration Pattern recognition Petroleum plays
Presented at the 2014 SPE NAICE Conference in Eko Hotel, Lagos, Aug 2014
As Nigerian operations expand into more challenging and costly operating environments, there is n... more As Nigerian operations expand into more challenging and costly operating environments, there is need for critical access to sound stratigraphic, depositional and reservoir facies models. The extraction of geomorphic insights and pattern recognition using predominantly 3D seismic data is a rapidly evolving discipline that facilitates the development of reservoir prediction models linked to significant plays especially in the deep. In this study a regional dataset which comprised of a merged 3D seismic volume, well logs, biostratigraphic, biofacies, paleobathymetry and core data from Eastern Niger Delta was interpreted and reviewed to show the overall structural, stratigraphic and architectural styles within the region to ensure that successes made in the past can be repeated and also make significant advances to ensure future exploration success. Hence, an added goal is to have a low-risk exploration workflow that is capable of correct prediction of reservoir rocks to be encountered in a new play and prospect. Three plays have been identified from this study: (1) Shelf Edge Deltas, (2) Pinch-Out Play and (3) Hanging Wall Play. Each play displays a unique morphology, seismic expression, structural configuration, migration pathway, seal integrity and reservoir dispersal pattern. These prediction models provide play based exploration targets for areas with similar depositional settings. The successful application of this technique serve to encourage exploration in the Niger Delta Basin by adopting strategies where seismic stratigraphy will be the most likely means to provide drilling targets to more independent operators.
Technical presentation at the American Association of Petroleum Geologists Annual Conference and Exhibition, USA, Apr 2014
The study documents the regional stratigraphic framework and structural configurations of three b... more The study documents the regional stratigraphic framework and structural configurations of three blocks, H, J, and K located in shallow offshore, Niger Delta. The purpose of the study is to use sequence stratigraphic framework, seismic facies, geomorphology and structural configuration as tools for prediction of reservoir distributions in relation to structuration. The dataset consists of 3D seismic volume, wireline log suites (gamma ray, resistivity and sonic), biofacies, palynological and foraminiferal biozones and Niger Delta Chronostratigraphic chart. A total of 15 wells drilled in these blocks within the last twenty years were studied. The ages (Ma) of the maximum flooding surfaces identified range from 3.9-11.5Ma while that of the sequence boundaries range from 4.1-10.6Ma. On strike there was a variation in the number of sequences from three to five and correlated wells tends to be older in age and shallower in paleobathymetry eastward.
Flattening at 5.0Ma maximum flooding surface above 5.6Ma sequence boundaries shows that updip, the system tracts gradually thin out eastward showing that rate of creation of accommodation increases westward. We attribute the increase in accommodation westward to the structural configuration of the area which allowed the formation of collapsed crest structures in the H-Block while the eastward decrease in accommodation is associated with closely spaced flank faults informally called the K-faults in the K-block. Downdip, the correlation shows that individual system tracts thickened at the center and thinned at the flanks. We interpreted this feature as channels in seismic with concave upward geometry at the center with the thickened center representing an incised valley created during base level fall at 5.6Ma sequence boundary which got filled at the next sea-level rise.
Six seismic facies were interpreted, which delineate the distribution of lithofacies and their environments of deposition across the strike. Seismic geomorphologic characterization showed that the intensity of incision increases downward from 5.6Ma to 6.7Ma sequence boundaries suggesting high potentials for reservoir presence at deeper intervals and thus making prospectivity robust for deeper plays in the area.
Presented at the 2013 NAPE International Conference in Eko Hotel, Lagos, Nov 2013
The study area lies within two SPDC OML Blocks A and B that straddle the Northern Delta and Great... more The study area lies within two SPDC OML Blocks A and B that straddle the Northern Delta and Greater Ughelli Depobelt. It is part of an expansion of Nigerian gas project that is targeted to deliver gas primarily to the domestic market by second quarter of 2018. Reservoir presence and quality were considered major risks in the Upper Oligocene to Eocene play below current well penetration in the study area.
This regional study made use of 3D Pre-Stack Depth Migration (PSDM) seismic volume re-processed in 2011; well logs, biostratigraphic and biofacies data. A robust interpretation workflow consisting of advanced Shell 3D seismic interpretation technology, structural framework interpretation, sequence stratigraphy, attributes analysis and geobody interpretation was used to create new play concepts.
3D seismic geometries interpreted to be prograding Shelf Edge Deltas with internal sand bodies were delineated within the Upper Oligocene to Eocene play below current well penetration. Sand fairway and gross depositional environment maps were also created. The current play concept clearly shows the possibility of finding Upper Oligocene to Eocene shelf edge delta reservoirs and upper slope channels.
Thus, the application of geological models derived from robust seismic technology will enable Shell Exploration in Nigeria to make critical business decisions on drilling the potential Upper Oligocene to Eocene play. This is very significant to the future gas development plan onshore Niger Delta.
The structural framework and stratigraphy of the Ariki Field in the Western Shallow Offshore Depo... more The structural framework and stratigraphy of the Ariki Field in the Western Shallow Offshore Depobelt, Niger Delta Basin, Nigeria are interpreted using well logs and 3-D seismic data, and the control of rift on hydrocarbon accumulation is analyzed. Five maximum flooding surfaces and five sequence boundaries are identified in the major reservoir succession of Agbada Formation in the field; and the structural framework of the field is controlled by the major growth faults, minor faults and rollover anticlines formed by synsedimentary tectonic movements. There are a total of seven faults identified across the field, including three major faults and four minor faults. On the western flank of the field, graben and horst-like structures were bounded by minor faults. Fault throw analysis shows that below 1800 ms, the major faults with large fault throws act as hydrocarbon migration pathways, while above 1 800 ms, faults with small throws act as seals of hydrocarbon traps. There are four-way dip rollover anticlines and three-way downdip traps created by the minor faults. Six other prospective traps (drilling targets) were identified, which have promising oil accumulation potential.
As Nigerian operations expand into more
challenging and costly operating environments of deepfron... more As Nigerian operations expand into more challenging and costly operating environments of deepfrontiers, there is need for critical access to sound stratigraphic, depositional and reservoir facies models. The extraction of facies types from geometric insights and pattern recognition using predominantly 3D seismic data is a rapidly evolving discipline that facilitates the development of reservoir prediction models linked to significant plays. Play based exploration approach such as this provides the critical link between regional observations and prospect generation. In this study a regional dataset which comprised of a merged 3D seismic volume, well logs, biostratigraphic, biofacies, paleobathymetry and core data from Eastern Niger Delta was interpreted. Results clearly show the overall structural, stratigraphic and architectural styles within the region to ensure that successes achieved in the past can be repeated and also significant advances made to ensure future exploration success. An added outcome is a low-risk exploration workflow that is capable of correctly predicting reservoir rocks to be encountered in a new play and prospect. Three plays have been identified from this study: (1) shelf edge deltas, (2) pinch-out play and (3) hanging wall play. Each play displays a unique morphology, seismic expression, structural configuration, migration pathway, seal integrity and reservoir dispersal pattern. These prediction models provide play based exploration targets for areas with similar depositional settings. The successful application of this technique serve to encourage exploration in the Niger Delta Basin by adopting strategies where seismic stratigraphy will be the most likely means to provide drilling targets to more independent operators. Keywords: Seismic stratigraphy Structural configuration Pattern recognition Petroleum plays
Abstract As Nigerian operations expand into more
challenging and costly operating environments of... more Abstract As Nigerian operations expand into more challenging and costly operating environments of deep frontiers, there is need for critical access to sound stratigraphic, depositional and reservoir facies models. The extraction of facies types from geometric insights and pattern recognition using predominantly 3D seismic data is a rapidly evolving discipline that facilitates the development of reservoir prediction models linked to significant plays. Play based exploration approach such as this provides the critical link between regional observations and prospect generation. In this study a regional dataset which comprised of a merged 3D seismic volume, well logs, biostratigraphic, biofacies, paleobathymetry and core data from Eastern Niger Delta was interpreted. Results clearly show the overall structural, stratigraphic and architectural styles within the region to ensure that successes achieved in the past can be repeated and also significant advances made to ensure future exploration success. An added outcome is a low-risk exploration workflow that is capable of correctly predicting reservoir rocks to be encountered in a new play and prospect. Three plays have been identified from this study: (1) shelf edge deltas, (2) pinch-out play and (3) hanging wall play. Each play displays a unique morphology, seismic expression, structural configuration, migration pathway, seal integrity and reservoir dispersal pattern. These prediction models provide play based exploration targets for areas with similar depositional settings. The successful application of this technique serve to encourage exploration in the Niger Delta Basin by adopting strategies where seismic stratigraphy will be the most likely means to provide drilling targets to more independent operators. Keywords Seismic stratigraphy Structural configuration Pattern recognition Petroleum plays
Presented at the 2014 SPE NAICE Conference in Eko Hotel, Lagos, Aug 2014
As Nigerian operations expand into more challenging and costly operating environments, there is n... more As Nigerian operations expand into more challenging and costly operating environments, there is need for critical access to sound stratigraphic, depositional and reservoir facies models. The extraction of geomorphic insights and pattern recognition using predominantly 3D seismic data is a rapidly evolving discipline that facilitates the development of reservoir prediction models linked to significant plays especially in the deep. In this study a regional dataset which comprised of a merged 3D seismic volume, well logs, biostratigraphic, biofacies, paleobathymetry and core data from Eastern Niger Delta was interpreted and reviewed to show the overall structural, stratigraphic and architectural styles within the region to ensure that successes made in the past can be repeated and also make significant advances to ensure future exploration success. Hence, an added goal is to have a low-risk exploration workflow that is capable of correct prediction of reservoir rocks to be encountered in a new play and prospect. Three plays have been identified from this study: (1) Shelf Edge Deltas, (2) Pinch-Out Play and (3) Hanging Wall Play. Each play displays a unique morphology, seismic expression, structural configuration, migration pathway, seal integrity and reservoir dispersal pattern. These prediction models provide play based exploration targets for areas with similar depositional settings. The successful application of this technique serve to encourage exploration in the Niger Delta Basin by adopting strategies where seismic stratigraphy will be the most likely means to provide drilling targets to more independent operators.
Technical presentation at the American Association of Petroleum Geologists Annual Conference and Exhibition, USA, Apr 2014
The study documents the regional stratigraphic framework and structural configurations of three b... more The study documents the regional stratigraphic framework and structural configurations of three blocks, H, J, and K located in shallow offshore, Niger Delta. The purpose of the study is to use sequence stratigraphic framework, seismic facies, geomorphology and structural configuration as tools for prediction of reservoir distributions in relation to structuration. The dataset consists of 3D seismic volume, wireline log suites (gamma ray, resistivity and sonic), biofacies, palynological and foraminiferal biozones and Niger Delta Chronostratigraphic chart. A total of 15 wells drilled in these blocks within the last twenty years were studied. The ages (Ma) of the maximum flooding surfaces identified range from 3.9-11.5Ma while that of the sequence boundaries range from 4.1-10.6Ma. On strike there was a variation in the number of sequences from three to five and correlated wells tends to be older in age and shallower in paleobathymetry eastward.
Flattening at 5.0Ma maximum flooding surface above 5.6Ma sequence boundaries shows that updip, the system tracts gradually thin out eastward showing that rate of creation of accommodation increases westward. We attribute the increase in accommodation westward to the structural configuration of the area which allowed the formation of collapsed crest structures in the H-Block while the eastward decrease in accommodation is associated with closely spaced flank faults informally called the K-faults in the K-block. Downdip, the correlation shows that individual system tracts thickened at the center and thinned at the flanks. We interpreted this feature as channels in seismic with concave upward geometry at the center with the thickened center representing an incised valley created during base level fall at 5.6Ma sequence boundary which got filled at the next sea-level rise.
Six seismic facies were interpreted, which delineate the distribution of lithofacies and their environments of deposition across the strike. Seismic geomorphologic characterization showed that the intensity of incision increases downward from 5.6Ma to 6.7Ma sequence boundaries suggesting high potentials for reservoir presence at deeper intervals and thus making prospectivity robust for deeper plays in the area.
Presented at the 2013 NAPE International Conference in Eko Hotel, Lagos, Nov 2013
The study area lies within two SPDC OML Blocks A and B that straddle the Northern Delta and Great... more The study area lies within two SPDC OML Blocks A and B that straddle the Northern Delta and Greater Ughelli Depobelt. It is part of an expansion of Nigerian gas project that is targeted to deliver gas primarily to the domestic market by second quarter of 2018. Reservoir presence and quality were considered major risks in the Upper Oligocene to Eocene play below current well penetration in the study area.
This regional study made use of 3D Pre-Stack Depth Migration (PSDM) seismic volume re-processed in 2011; well logs, biostratigraphic and biofacies data. A robust interpretation workflow consisting of advanced Shell 3D seismic interpretation technology, structural framework interpretation, sequence stratigraphy, attributes analysis and geobody interpretation was used to create new play concepts.
3D seismic geometries interpreted to be prograding Shelf Edge Deltas with internal sand bodies were delineated within the Upper Oligocene to Eocene play below current well penetration. Sand fairway and gross depositional environment maps were also created. The current play concept clearly shows the possibility of finding Upper Oligocene to Eocene shelf edge delta reservoirs and upper slope channels.
Thus, the application of geological models derived from robust seismic technology will enable Shell Exploration in Nigeria to make critical business decisions on drilling the potential Upper Oligocene to Eocene play. This is very significant to the future gas development plan onshore Niger Delta.
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Papers by David Anomneze
challenging and costly operating environments of deepfrontiers,
there is need for critical access to sound stratigraphic,
depositional and reservoir facies models. The extraction
of facies types from geometric insights and pattern
recognition using predominantly 3D seismic data is a
rapidly evolving discipline that facilitates the development
of reservoir prediction models linked to significant plays.
Play based exploration approach such as this provides the
critical link between regional observations and prospect
generation. In this study a regional dataset which comprised
of a merged 3D seismic volume, well logs, biostratigraphic,
biofacies, paleobathymetry and core data from
Eastern Niger Delta was interpreted. Results clearly show
the overall structural, stratigraphic and architectural styles
within the region to ensure that successes achieved in the
past can be repeated and also significant advances made to
ensure future exploration success. An added outcome is a
low-risk exploration workflow that is capable of correctly
predicting reservoir rocks to be encountered in a new play
and prospect. Three plays have been identified from this
study: (1) shelf edge deltas, (2) pinch-out play and (3)
hanging wall play. Each play displays a unique morphology,
seismic expression, structural configuration, migration
pathway, seal integrity and reservoir dispersal
pattern. These prediction models provide play based
exploration targets for areas with similar depositional settings.
The successful application of this technique serve to
encourage exploration in the Niger Delta Basin by adopting
strategies where seismic stratigraphy will be the most
likely means to provide drilling targets to more independent
operators.
Keywords: Seismic stratigraphy Structural
configuration Pattern recognition Petroleum plays
challenging and costly operating environments of deep frontiers, there is need for critical access to sound stratigraphic, depositional and reservoir facies models. The extraction
of facies types from geometric insights and pattern
recognition using predominantly 3D seismic data is a
rapidly evolving discipline that facilitates the development
of reservoir prediction models linked to significant plays.
Play based exploration approach such as this provides the
critical link between regional observations and prospect
generation. In this study a regional dataset which comprised
of a merged 3D seismic volume, well logs, biostratigraphic,
biofacies, paleobathymetry and core data from Eastern Niger Delta was interpreted. Results clearly show the overall structural, stratigraphic and architectural styles within the region to ensure that successes achieved in the past can be repeated and also significant advances made to ensure future exploration success. An added outcome is a low-risk exploration workflow that is capable of correctly predicting reservoir rocks to be encountered in a new play and prospect. Three plays have been identified from this study: (1) shelf edge deltas, (2) pinch-out play and (3) hanging wall play. Each play displays a unique morphology, seismic expression, structural configuration, migration pathway, seal integrity and reservoir dispersal pattern. These prediction models provide play based
exploration targets for areas with similar depositional settings.
The successful application of this technique serve to
encourage exploration in the Niger Delta Basin by adopting
strategies where seismic stratigraphy will be the most
likely means to provide drilling targets to more independent
operators.
Keywords Seismic stratigraphy Structural
configuration Pattern recognition Petroleum plays
Flattening at 5.0Ma maximum flooding surface above 5.6Ma sequence boundaries shows that updip, the system tracts gradually thin out eastward showing that rate of creation of accommodation increases westward. We attribute the increase in accommodation westward to the structural configuration of the area which allowed the formation of collapsed crest structures in the H-Block while the eastward decrease in accommodation is associated with closely spaced flank faults informally called the K-faults in the K-block. Downdip, the correlation shows that individual system tracts thickened at the center and thinned at the flanks. We interpreted this feature as channels in seismic with concave upward geometry at the center with the thickened center representing an incised valley created during base level fall at 5.6Ma sequence boundary which got filled at the next sea-level rise.
Six seismic facies were interpreted, which delineate the distribution of lithofacies and their environments of deposition across the strike. Seismic geomorphologic characterization showed that the intensity of incision increases downward from 5.6Ma to 6.7Ma sequence boundaries suggesting high potentials for reservoir presence at deeper intervals and thus making prospectivity robust for deeper plays in the area.
This regional study made use of 3D Pre-Stack Depth Migration (PSDM) seismic volume re-processed in 2011; well logs, biostratigraphic and biofacies data. A robust interpretation workflow consisting of advanced Shell 3D seismic interpretation technology, structural framework interpretation, sequence stratigraphy, attributes analysis and geobody interpretation was used to create new play concepts.
3D seismic geometries interpreted to be prograding Shelf Edge Deltas with internal sand bodies were delineated within the Upper Oligocene to Eocene play below current well penetration. Sand fairway and gross depositional environment maps were also created. The current play concept clearly shows the possibility of finding Upper Oligocene to Eocene shelf edge delta reservoirs and upper slope channels.
Thus, the application of geological models derived from robust seismic technology will enable Shell Exploration in Nigeria to make critical business decisions on drilling the potential Upper Oligocene to Eocene play. This is very significant to the future gas development plan onshore Niger Delta.
challenging and costly operating environments of deepfrontiers,
there is need for critical access to sound stratigraphic,
depositional and reservoir facies models. The extraction
of facies types from geometric insights and pattern
recognition using predominantly 3D seismic data is a
rapidly evolving discipline that facilitates the development
of reservoir prediction models linked to significant plays.
Play based exploration approach such as this provides the
critical link between regional observations and prospect
generation. In this study a regional dataset which comprised
of a merged 3D seismic volume, well logs, biostratigraphic,
biofacies, paleobathymetry and core data from
Eastern Niger Delta was interpreted. Results clearly show
the overall structural, stratigraphic and architectural styles
within the region to ensure that successes achieved in the
past can be repeated and also significant advances made to
ensure future exploration success. An added outcome is a
low-risk exploration workflow that is capable of correctly
predicting reservoir rocks to be encountered in a new play
and prospect. Three plays have been identified from this
study: (1) shelf edge deltas, (2) pinch-out play and (3)
hanging wall play. Each play displays a unique morphology,
seismic expression, structural configuration, migration
pathway, seal integrity and reservoir dispersal
pattern. These prediction models provide play based
exploration targets for areas with similar depositional settings.
The successful application of this technique serve to
encourage exploration in the Niger Delta Basin by adopting
strategies where seismic stratigraphy will be the most
likely means to provide drilling targets to more independent
operators.
Keywords: Seismic stratigraphy Structural
configuration Pattern recognition Petroleum plays
challenging and costly operating environments of deep frontiers, there is need for critical access to sound stratigraphic, depositional and reservoir facies models. The extraction
of facies types from geometric insights and pattern
recognition using predominantly 3D seismic data is a
rapidly evolving discipline that facilitates the development
of reservoir prediction models linked to significant plays.
Play based exploration approach such as this provides the
critical link between regional observations and prospect
generation. In this study a regional dataset which comprised
of a merged 3D seismic volume, well logs, biostratigraphic,
biofacies, paleobathymetry and core data from Eastern Niger Delta was interpreted. Results clearly show the overall structural, stratigraphic and architectural styles within the region to ensure that successes achieved in the past can be repeated and also significant advances made to ensure future exploration success. An added outcome is a low-risk exploration workflow that is capable of correctly predicting reservoir rocks to be encountered in a new play and prospect. Three plays have been identified from this study: (1) shelf edge deltas, (2) pinch-out play and (3) hanging wall play. Each play displays a unique morphology, seismic expression, structural configuration, migration pathway, seal integrity and reservoir dispersal pattern. These prediction models provide play based
exploration targets for areas with similar depositional settings.
The successful application of this technique serve to
encourage exploration in the Niger Delta Basin by adopting
strategies where seismic stratigraphy will be the most
likely means to provide drilling targets to more independent
operators.
Keywords Seismic stratigraphy Structural
configuration Pattern recognition Petroleum plays
Flattening at 5.0Ma maximum flooding surface above 5.6Ma sequence boundaries shows that updip, the system tracts gradually thin out eastward showing that rate of creation of accommodation increases westward. We attribute the increase in accommodation westward to the structural configuration of the area which allowed the formation of collapsed crest structures in the H-Block while the eastward decrease in accommodation is associated with closely spaced flank faults informally called the K-faults in the K-block. Downdip, the correlation shows that individual system tracts thickened at the center and thinned at the flanks. We interpreted this feature as channels in seismic with concave upward geometry at the center with the thickened center representing an incised valley created during base level fall at 5.6Ma sequence boundary which got filled at the next sea-level rise.
Six seismic facies were interpreted, which delineate the distribution of lithofacies and their environments of deposition across the strike. Seismic geomorphologic characterization showed that the intensity of incision increases downward from 5.6Ma to 6.7Ma sequence boundaries suggesting high potentials for reservoir presence at deeper intervals and thus making prospectivity robust for deeper plays in the area.
This regional study made use of 3D Pre-Stack Depth Migration (PSDM) seismic volume re-processed in 2011; well logs, biostratigraphic and biofacies data. A robust interpretation workflow consisting of advanced Shell 3D seismic interpretation technology, structural framework interpretation, sequence stratigraphy, attributes analysis and geobody interpretation was used to create new play concepts.
3D seismic geometries interpreted to be prograding Shelf Edge Deltas with internal sand bodies were delineated within the Upper Oligocene to Eocene play below current well penetration. Sand fairway and gross depositional environment maps were also created. The current play concept clearly shows the possibility of finding Upper Oligocene to Eocene shelf edge delta reservoirs and upper slope channels.
Thus, the application of geological models derived from robust seismic technology will enable Shell Exploration in Nigeria to make critical business decisions on drilling the potential Upper Oligocene to Eocene play. This is very significant to the future gas development plan onshore Niger Delta.