Authors :
Onyewuchi Vin Chinedu; Minapuye, I .Odigi
Volume/Issue :
Volume 8 - 2023, Issue 8 - August
Google Scholar :
https://bit.ly/3TmGbDi
Scribd :
https://tinyurl.com/fzkzjya5
DOI :
https://doi.org/10.5281/zenodo.8265113
Abstract :
Petrophysical evaluation and flow unit
assessment of the D-3 reservoir sand in the Vin field,
offshore Niger Delta has been performed. The aims of
the study are to assess the reservoir quality and flow
units in the field through the integration of results from
core analysis, production data, seismic data, and
petrophysical parameters. Well log suites from 22 wells
comprising gamma ray, resistivity, neutron, density,
seismic data, and ditch cutting samples were obtained
and analyzed. Petrophysical evaluation was carried out
using various petrophysical computations. Field wide
correlation from the western to the eastern part of the
field was also carried out. Assessment of the flow unit
was done using Flow Zone Indicator (FZI), Stratified
Modified Lorenz plot, porosity-permeability cross plot
and Winland technique. Field wide correlation revealed
that the reservoir is laterally extensive and thins towards
the east. Reservoir rock qualities were generally very
good with Volume of shale ranging from 0.08 to 0.14,
with an average of 0.11. Porosity values ranges from 0.22
to 0.40 with an average value of 0.34 while permeability
values is between 130mD to 10,000 mD, with an average
value of 2692 mD. Average water saturation values
ranges from 0.17 to 0.42, while the average net to gross
ratio is 0.89. The bulk water volume values are nearly
constant, meaning the reservoir is homogenous and at
irreducible water saturation. This implies that the
reservoir can produce water-free hydrocarbon. The
Stratified Modified Lorenz (SML) plot revealed three
flow units with two high speed zones (FZ 1 and FZ 3)
and one low speed zone (FZ 2). Based on the FZI, three
flow units (FZ-1 to FZ-3) were identified in the reservoir
with FZ-1 having the best reservoir quality. Winland
technique presents three Petrofacies (Mega porous,
Macro porous, Micro porous). Porosity-permeability
cross plot also revealed three distinct facies based on
ditch cuttings description. These facies are: U1- fine
grained well sorted sandstone, U2- very fine grained well
sorted sandstone, and U3- very fine grained shaley
sandstone. Each of these facies is associated to a unique
flow unit meaning that different depositional
environment and diagenetic processes control the
geometry of the reservoir and consequently the flow unit
index. By modelling the reservoir behaviour and
simulating their behaviour, uncertainties associated with
field development in the Vin field and fields in the
eastern Niger Delta will be reduced from the outcome of
this study.
Keywords :
Baffle, Heterogeneity, Flowzone, Synsedimentary, Dip Closure.
Petrophysical evaluation and flow unit
assessment of the D-3 reservoir sand in the Vin field,
offshore Niger Delta has been performed. The aims of
the study are to assess the reservoir quality and flow
units in the field through the integration of results from
core analysis, production data, seismic data, and
petrophysical parameters. Well log suites from 22 wells
comprising gamma ray, resistivity, neutron, density,
seismic data, and ditch cutting samples were obtained
and analyzed. Petrophysical evaluation was carried out
using various petrophysical computations. Field wide
correlation from the western to the eastern part of the
field was also carried out. Assessment of the flow unit
was done using Flow Zone Indicator (FZI), Stratified
Modified Lorenz plot, porosity-permeability cross plot
and Winland technique. Field wide correlation revealed
that the reservoir is laterally extensive and thins towards
the east. Reservoir rock qualities were generally very
good with Volume of shale ranging from 0.08 to 0.14,
with an average of 0.11. Porosity values ranges from 0.22
to 0.40 with an average value of 0.34 while permeability
values is between 130mD to 10,000 mD, with an average
value of 2692 mD. Average water saturation values
ranges from 0.17 to 0.42, while the average net to gross
ratio is 0.89. The bulk water volume values are nearly
constant, meaning the reservoir is homogenous and at
irreducible water saturation. This implies that the
reservoir can produce water-free hydrocarbon. The
Stratified Modified Lorenz (SML) plot revealed three
flow units with two high speed zones (FZ 1 and FZ 3)
and one low speed zone (FZ 2). Based on the FZI, three
flow units (FZ-1 to FZ-3) were identified in the reservoir
with FZ-1 having the best reservoir quality. Winland
technique presents three Petrofacies (Mega porous,
Macro porous, Micro porous). Porosity-permeability
cross plot also revealed three distinct facies based on
ditch cuttings description. These facies are: U1- fine
grained well sorted sandstone, U2- very fine grained well
sorted sandstone, and U3- very fine grained shaley
sandstone. Each of these facies is associated to a unique
flow unit meaning that different depositional
environment and diagenetic processes control the
geometry of the reservoir and consequently the flow unit
index. By modelling the reservoir behaviour and
simulating their behaviour, uncertainties associated with
field development in the Vin field and fields in the
eastern Niger Delta will be reduced from the outcome of
this study.
Keywords :
Baffle, Heterogeneity, Flowzone, Synsedimentary, Dip Closure.
