A proposed solution to the determination of water saturation: using a modelled equation

Abstract Reservoir characterization is an important phase in oil and gas field development, which takes place during the appraisal phase of either a green field or a brown field upon which further development options are considered. Water saturation is a very important parameter in the general descr...

Full description

Bibliographic Details
Main Authors: Jethro Sam-Marcus, Efeoghene Enaworu, Oluwatosin J. Rotimi, Ifeanyi Seteyeobot
Format: Article
Language:English
Published: SpringerOpen 2018-03-01
Series:Journal of Petroleum Exploration and Production Technology
Subjects:
Online Access:http://link.springer.com/article/10.1007/s13202-018-0453-4
_version_ 1818018447590686720
author Jethro Sam-Marcus
Efeoghene Enaworu
Oluwatosin J. Rotimi
Ifeanyi Seteyeobot
author_facet Jethro Sam-Marcus
Efeoghene Enaworu
Oluwatosin J. Rotimi
Ifeanyi Seteyeobot
author_sort Jethro Sam-Marcus
collection DOAJ
description Abstract Reservoir characterization is an important phase in oil and gas field development, which takes place during the appraisal phase of either a green field or a brown field upon which further development options are considered. Water saturation is a very important parameter in the general description of the reservoir as well as equity determination and dynamic modelling. Numerous equations have been developed which have been used to determine water saturation, but calculated water saturation values have been inconsistent with the saturation values determined from core analysis. This is generally due to their inability to account for the varying distribution of shale in the reservoir and the often incorrectness of their underlying assumptions. The major aim of this research is to develop a model which can be used to determine water saturation values using data from well logs; also, to compare the developed model with other existing models used in the oil and gas industry, using data from core analysis and well logs as the input data; and then finally, to discuss the results of the comparison, using the core-derived saturation values as the bench mark. The model is based on a parallel resistivity model, which is based on the assumption that the conductivity of the sandstone term and the shale term exist in parallel in the shaly-sand reservoir. The shale term in the reservoir of the model is based on the assumption that the clay-bound electrons do not move in the same conductivity path as the sandstone electrons. The shale conductivity term is based on the bound water saturation and the bound water resistivity. The modelled equation was compared in two scenarios using well log data and core data from two different reservoirs, and the model showed consistency in predicting the average water saturation in both reservoirs. The results of the comparison were positive for the modelled equation, as it gave coherent results in both comparison scenarios and matched reasonably the average water saturation of the selected reservoirs. This developed model can serve as an accurate means of determining water saturation in reservoirs, especially for reservoirs with similar characteristics as the selected reservoirs in this research.
first_indexed 2024-04-14T07:39:21Z
format Article
id doaj.art-445950dc5a034219970d5925b1c6fbb2
institution Directory Open Access Journal
issn 2190-0558
2190-0566
language English
last_indexed 2024-04-14T07:39:21Z
publishDate 2018-03-01
publisher SpringerOpen
record_format Article
series Journal of Petroleum Exploration and Production Technology
spelling doaj.art-445950dc5a034219970d5925b1c6fbb22022-12-22T02:05:33ZengSpringerOpenJournal of Petroleum Exploration and Production Technology2190-05582190-05662018-03-01841009101510.1007/s13202-018-0453-4A proposed solution to the determination of water saturation: using a modelled equationJethro Sam-Marcus0Efeoghene Enaworu1Oluwatosin J. Rotimi2Ifeanyi Seteyeobot3Petroleum Engineering Department, Covenant UniversityPetroleum Engineering Department, Covenant UniversityPetroleum Engineering Department, Covenant UniversityPetroleum Engineering Department, Covenant UniversityAbstract Reservoir characterization is an important phase in oil and gas field development, which takes place during the appraisal phase of either a green field or a brown field upon which further development options are considered. Water saturation is a very important parameter in the general description of the reservoir as well as equity determination and dynamic modelling. Numerous equations have been developed which have been used to determine water saturation, but calculated water saturation values have been inconsistent with the saturation values determined from core analysis. This is generally due to their inability to account for the varying distribution of shale in the reservoir and the often incorrectness of their underlying assumptions. The major aim of this research is to develop a model which can be used to determine water saturation values using data from well logs; also, to compare the developed model with other existing models used in the oil and gas industry, using data from core analysis and well logs as the input data; and then finally, to discuss the results of the comparison, using the core-derived saturation values as the bench mark. The model is based on a parallel resistivity model, which is based on the assumption that the conductivity of the sandstone term and the shale term exist in parallel in the shaly-sand reservoir. The shale term in the reservoir of the model is based on the assumption that the clay-bound electrons do not move in the same conductivity path as the sandstone electrons. The shale conductivity term is based on the bound water saturation and the bound water resistivity. The modelled equation was compared in two scenarios using well log data and core data from two different reservoirs, and the model showed consistency in predicting the average water saturation in both reservoirs. The results of the comparison were positive for the modelled equation, as it gave coherent results in both comparison scenarios and matched reasonably the average water saturation of the selected reservoirs. This developed model can serve as an accurate means of determining water saturation in reservoirs, especially for reservoirs with similar characteristics as the selected reservoirs in this research.http://link.springer.com/article/10.1007/s13202-018-0453-4Reservoir characterizationWater saturationBound water saturationBound water resistivityVolume of shaleCore analysis
spellingShingle Jethro Sam-Marcus
Efeoghene Enaworu
Oluwatosin J. Rotimi
Ifeanyi Seteyeobot
A proposed solution to the determination of water saturation: using a modelled equation
Journal of Petroleum Exploration and Production Technology
Reservoir characterization
Water saturation
Bound water saturation
Bound water resistivity
Volume of shale
Core analysis
title A proposed solution to the determination of water saturation: using a modelled equation
title_full A proposed solution to the determination of water saturation: using a modelled equation
title_fullStr A proposed solution to the determination of water saturation: using a modelled equation
title_full_unstemmed A proposed solution to the determination of water saturation: using a modelled equation
title_short A proposed solution to the determination of water saturation: using a modelled equation
title_sort proposed solution to the determination of water saturation using a modelled equation
topic Reservoir characterization
Water saturation
Bound water saturation
Bound water resistivity
Volume of shale
Core analysis
url http://link.springer.com/article/10.1007/s13202-018-0453-4
work_keys_str_mv AT jethrosammarcus aproposedsolutiontothedeterminationofwatersaturationusingamodelledequation
AT efeogheneenaworu aproposedsolutiontothedeterminationofwatersaturationusingamodelledequation
AT oluwatosinjrotimi aproposedsolutiontothedeterminationofwatersaturationusingamodelledequation
AT ifeanyiseteyeobot aproposedsolutiontothedeterminationofwatersaturationusingamodelledequation
AT jethrosammarcus proposedsolutiontothedeterminationofwatersaturationusingamodelledequation
AT efeogheneenaworu proposedsolutiontothedeterminationofwatersaturationusingamodelledequation
AT oluwatosinjrotimi proposedsolutiontothedeterminationofwatersaturationusingamodelledequation
AT ifeanyiseteyeobot proposedsolutiontothedeterminationofwatersaturationusingamodelledequation