This study used elastic impedance inversion and pre-stack attribute analysis on 3D seismic data with limited well control to identify productive zones in an offshore Iranian reservoir. Poisson dampening factor and Lame parameters extracted from pre-stack simultaneous inversion effectively delineated hydrocarbon-bearing areas, validated by crossplots of elastic impedance volumes. The attribute analysis results at well locations were generalized to the full seismic volume since the reservoir was considered laterally homogeneous.
Field and Theoretical Analysis of Accelerated Consolidation Using Vertical Dr...inventionjournals
Mumbai is the region consisting of soft compressible marine clay deposits. There are several construction problems on such soils and thus ground improvement is need to be carried out. Vertical drains is generally preferred technique as accelerated settlement is achieved during the construction phase itself if planned accordingly. The concept of vertical drains is based on the theory of three dimensional consolidation as described by Terzaghi (1943). Based on this concept, a consolidation programme is developed and an attempt is made to determine the field to laboratory coefficient of vertical consolidation ratio by Taylor’s Square Root of Time Method and Casagrande’s Logarithm of Time Fitting Method for this region. Based on this, the rate of consolidation and time required for consolidation in the field can be determined knowing the consolidation parameters. Equations are developed by using output of the programme and it is explained.
On Similarity of Differential Capacity and Capillary Pressure FractalKhalid Al-Khidir
On Similarity of Differential Capacity and Capillary Pressure Fractal Dimensions for Characterizing Shajara Reservoirs of the Permo-Carboniferous Shajara Formation, Saudi Arabia
The document provides information on prospect evaluation methodology for oil companies and governments. It discusses how prospect evaluation is used for resource assessment, contracting areas, work commitments, and investment decisions. The methodology includes volumetric and economic evaluations using seismic interpretation, mapping, cash flow analysis, and other factors. Equations and parameters involved in calculating the volumes of oil and gas in-place are also presented, such as pore volume, recovery factors, and formation properties. An example calculation of recoverable oil resources is included to demonstrate the process.
This document summarizes methods for estimating CO2 storage resource and capacity in deep saline formations. It discusses terminology, proposed classification systems for storage resource levels, and open and closed system methodologies. Methodologies from the DOE, CSLF, IEAGHG, and USGS are compared. The document also discusses determining storage coefficients through numerical simulation and developing storage coefficients at different scales from site-specific to formation-level. Key references on the topic are also listed.
The document presents an analytical solution for modeling groundwater flow in a multi-aquifer system considering vertical flow in the wellbore and well loss due to friction. It extends a previous single aquifer solution to consider two interconnected aquifers separated by an aquiclude. Simultaneous equations are formulated using Bernoulli's theorem under hydrostatic conditions to compute water flow between the two aquifers and well for both steady and unsteady well water level conditions. The solution technique aims to more scientifically and economically characterize parameters in multi-aquifer systems compared to previous approaches that treated interconnected aquifers as isolated.
CO2-Driven Enhanced Gas Recovery and Storage in Depleted Shale Reservoir- A N...Steve Wittrig
1) The document discusses using numerical simulation to analyze CO2-enhanced gas recovery and storage in depleted shale gas reservoirs. It aims to maximize methane production while delaying CO2 breakthrough and maximizing CO2 storage.
2) Different injection scenarios are defined based on modifications to well patterns, reservoir characteristics, fracture properties, sorption parameters, and operational constraints. The scenarios vary the spacing between injection and production wells.
3) The best injection practice will be proposed based on analyzing different scenarios to enhance methane recovery and minimize CO2 production from the reservoir while storing more CO2.
This study used elastic impedance inversion and pre-stack attribute analysis on 3D seismic data with limited well control to identify productive zones in an offshore Iranian reservoir. Poisson dampening factor and Lame parameters extracted from pre-stack simultaneous inversion effectively delineated hydrocarbon-bearing areas, validated by crossplots of elastic impedance volumes. The attribute analysis results at well locations were generalized to the full seismic volume since the reservoir was considered laterally homogeneous.
Field and Theoretical Analysis of Accelerated Consolidation Using Vertical Dr...inventionjournals
Mumbai is the region consisting of soft compressible marine clay deposits. There are several construction problems on such soils and thus ground improvement is need to be carried out. Vertical drains is generally preferred technique as accelerated settlement is achieved during the construction phase itself if planned accordingly. The concept of vertical drains is based on the theory of three dimensional consolidation as described by Terzaghi (1943). Based on this concept, a consolidation programme is developed and an attempt is made to determine the field to laboratory coefficient of vertical consolidation ratio by Taylor’s Square Root of Time Method and Casagrande’s Logarithm of Time Fitting Method for this region. Based on this, the rate of consolidation and time required for consolidation in the field can be determined knowing the consolidation parameters. Equations are developed by using output of the programme and it is explained.
On Similarity of Differential Capacity and Capillary Pressure FractalKhalid Al-Khidir
On Similarity of Differential Capacity and Capillary Pressure Fractal Dimensions for Characterizing Shajara Reservoirs of the Permo-Carboniferous Shajara Formation, Saudi Arabia
The document provides information on prospect evaluation methodology for oil companies and governments. It discusses how prospect evaluation is used for resource assessment, contracting areas, work commitments, and investment decisions. The methodology includes volumetric and economic evaluations using seismic interpretation, mapping, cash flow analysis, and other factors. Equations and parameters involved in calculating the volumes of oil and gas in-place are also presented, such as pore volume, recovery factors, and formation properties. An example calculation of recoverable oil resources is included to demonstrate the process.
This document summarizes methods for estimating CO2 storage resource and capacity in deep saline formations. It discusses terminology, proposed classification systems for storage resource levels, and open and closed system methodologies. Methodologies from the DOE, CSLF, IEAGHG, and USGS are compared. The document also discusses determining storage coefficients through numerical simulation and developing storage coefficients at different scales from site-specific to formation-level. Key references on the topic are also listed.
The document presents an analytical solution for modeling groundwater flow in a multi-aquifer system considering vertical flow in the wellbore and well loss due to friction. It extends a previous single aquifer solution to consider two interconnected aquifers separated by an aquiclude. Simultaneous equations are formulated using Bernoulli's theorem under hydrostatic conditions to compute water flow between the two aquifers and well for both steady and unsteady well water level conditions. The solution technique aims to more scientifically and economically characterize parameters in multi-aquifer systems compared to previous approaches that treated interconnected aquifers as isolated.
CO2-Driven Enhanced Gas Recovery and Storage in Depleted Shale Reservoir- A N...Steve Wittrig
1) The document discusses using numerical simulation to analyze CO2-enhanced gas recovery and storage in depleted shale gas reservoirs. It aims to maximize methane production while delaying CO2 breakthrough and maximizing CO2 storage.
2) Different injection scenarios are defined based on modifications to well patterns, reservoir characteristics, fracture properties, sorption parameters, and operational constraints. The scenarios vary the spacing between injection and production wells.
3) The best injection practice will be proposed based on analyzing different scenarios to enhance methane recovery and minimize CO2 production from the reservoir while storing more CO2.
Advances in Rock Physics Modelling and Improved Estimation of CO2 Saturation, Giorgos Papageorgiou - Geophysical Modelling for CO2 Storage, Leeds, 3 November 2015
This document discusses modeling groyne placement on river bends based on sedimentation analysis using numerical simulation with the finite difference method. The goal is to determine optimal groyne placement by considering sediment accumulation volumes in groyne fields.
The study plans to simulate 450 cases combining various groyne positions, lengths, flow velocities, bend radii, and suspended sediment concentrations. Conservation equations for mass and momentum will be used to develop the mathematical model. Validation and verification processes will evaluate the agreement between experimental data and model predictions.
Regression analysis of simulation results will determine suitability coefficients to obtain relationships between parameters like Froude number and groyne length, providing guidance on best distances between groynes. The numerical model aims
This document describes a Runge-Kutta Discontinuous Galerkin method for approximating the shallow water equations. The method introduces two techniques: 1) a flux modification technique to derive a well-balanced scheme that preserves steady states at rest with variable bathymetry, and 2) a slope modification technique to properly handle flooding and drying of water. Numerical results are presented to illustrate the performance of the proposed scheme.
Effect of Height and Surface Roughness of a Broad Crested Weir on the Dischar...RafidAlboresha
Weir is usually incorporated as control or regulation devices in hydraulic systems,
with flow measurement as their secondary. It is normally intended for use in the field and thus
to regulate broad discharges. Broad-Crested weir is among the oldest common weir types. In this
paper, the effect of height and surface roughness for different Board Crested weirs models were
studied on discharge coefficient (Cd) in a horizontal open channel. In the crest of the weir,
certain materials may be combined with concrete (e.g., boulders) or may be used as cladding to
minimize the effect of water overflow (e.g. stone). The weir surface should not be considered
smooth in this case, and the discharge coefficient (Cd) must be re-estimated. For these purposes, laboratory flume was used to study the effect of height and surface roughness on the discharge coefficients with four of the different weir models dimensions of the concrete blocks. In this study, the flow conditions were considered to be free water flow and the viscosity effect was neglected. In all cases, the weir height effect was directly proportional to the discharge coefficient while the surface roughness effect was found to be inversely proportional to the coefficient Cd of the case study.
Pore scale dynamics and the interpretation of flow processes - Martin Blunt, Imperial College London, at UKCCSRC specialist meeting Flow and Transport for CO2 Storage, 29-30 October 2015
The document discusses assessing relative permeabilities in geothermal reservoirs through analyzing the effect of gravity on relative permeabilities, performing laboratory measurements using real geothermal fluids, and calculating relative permeabilities from field data at several geothermal fields in Iceland. The results showed differences in relative permeabilities with flow direction and magnitude, and that wells within the same field can follow different relative permeability curves. Comparisons were made between laboratory and field measurements.
Measuring Hydrualic Conductivity Using Petro Physical Measurements 2013 compa...Christopher Estevez
This summary provides the key points from the document in 3 sentences:
The document discusses various methods for measuring hydraulic conductivity in soils more accurately in the field, including using gravitational methods for saturated soils and the Proportional Cylinder and Arya-Dierolf models for unsaturated soils. It analyzes modifying Darcy's law to account for centrifugal force when measuring saturated soils and how the Proportional Cylinder and Arya-Dierolf models can help determine unsaturated pore size and estimate hydraulic conductivity. Accurately measuring hydraulic conductivity is important for environmental cleanup efforts to more efficiently remove contaminants from lands.
1) The document discusses assessing uncertainty in time-lapse seismic response due to geomechanical deformation.
2) It presents a multi-physics solution that couples fluid flow and geomechanics modeling to better understand stress changes over time.
3) An example application to the Valhall oil field models pore pressure changes and resulting geomechanical effects, partitioning the domain for parallel modeling of the overburden, reservoir, and underburden.
This document summarizes a study on predicting the post-breakthrough performance of simultaneous water and gas coning in horizontal wells. A reservoir model was created using reservoir simulation software to model an oil zone between a gas cap and aquifer. Sensitivity analysis was performed by varying reservoir and fluid parameters to determine which most influence coning behavior. Correlations were developed using regression analysis to predict breakthrough time, gas-oil ratio (GOR), and water-oil ratio (WOR) based on the height of the oil column above and below perforations. The correlations can be used to estimate post-breakthrough performance in horizontal wells experiencing simultaneous water and gas coning.
Passive seismic monitoring for CO2 storage sites - Anna Stork, University of Bristol at UKCCSRC specialist meeting Geophysical modelling for CO2 storage, monitoring and appraisal, 3 November 2015
2014 a method for evaluation of water flooding performance in fractured res...AliMukhtar24
This document presents a new mathematical model for evaluating water flooding performance in fractured reservoirs. The model transforms a dual-porosity reservoir into an equivalent single-porosity model using a pseudo relative permeability method. This allows fractures and matrix to each have their own permeability, porosity, saturation, and relative permeability parameters. The model also accounts for imbibition effects by modifying an existing equation. The investigation shows imbibition can impact recovery and lower production rates can improve water flooding by delaying breakthrough and controlling water cut rise. A new chart is proposed to estimate ultimate recovery based on water cut versus recovery curves. The model is shown to estimate recovery within 2% of simulation results for two reservoirs, proving it a reliable evaluation method.
1) The document analytically solves the nonisothermal Buckley-Leverett problem for two-phase immiscible flow in porous media including a tracer component and temperature effects.
2) Mass balances for the fluids and tracer and a convective heat balance equation are formulated and solved using the method of characteristics.
3) The solutions can be used to analyze pressure transients, interpret formation testing, calculate temperature front propagation during waterflooding, and benchmark simulators.
The detectability of free-phase migrating CO2Rami Eid
1) The document investigates the detectability of migrating carbon dioxide (CO2) using rock physics and seismic modeling of a theoretical sandstone reservoir.
2) Three fluid saturation distribution models were assessed to capture a range of possible seismic responses: uniform, patchy, and modified patchy saturation.
3) Results show the fluid distribution model and relative permeability-capillary pressure curves significantly impact the detectability of migrating CO2, with patchy distributions and site-specific curves yielding lower detectability.
Modelling Fault Reactivation, Induced Seismicity, and Leakage During Underground CO2 Injection, Jonny Rutquvist - Geophysical Modelling for CO2 Storage, Leeds, 3 November 2015
1. The document discusses applying multi-curve reconstruction technology to seismic inversion to improve accuracy and reliability. It focuses on reconstructing SP and RMN curves from well logs that are affected by various distortions.
2. The process of reconstructing the curves involves removing baseline drift, standardizing values, applying linear filtering, and fitting the curves. This removes interference and retains valid lithological information.
3. Reconstructing high quality curves improves the resolution and credibility of seismic inversion results. The method is shown to effectively predict sand distribution with little error.
This document provides an introduction to enhanced oil recovery (EOR) techniques using carbon dioxide injection in a heterogeneous reservoir. It discusses primary, secondary, and tertiary recovery methods and explains that EOR processes are now commonly classified based on the recovery method rather than chronological stage. The document will analyze CO2 injection as a tertiary method to improve oil recovery from a reservoir with heterogeneity, using reservoir simulation and case studies.
K.E. Al-Khidir, M.S. Benzagouta
Department of Petroleum Engineering and Natural Gas, College of Engineering,
King Saud University, Saudi Arabia
К.Е. Аль-Хидир, М.С. Бензагута
Инженерный колледж, Университет короля Сауда
Abstract. With reference to the reservoir characterization regarding the Khuff Formation – Khurtam Member (KSA), better reservoir quality prediction can be assigned to
the characterization of its physical properties. These properties determination are depending on facies description. These properties can be erratic according to the diagenetic change and control on pore geometrical attributes and reservoir characterization. In this
investigation, permeability and porosity have been measured in the laboratory. Rock Quality Index (RQI), flow zone index (FZI) as well as porosity groups have been
calculated. The use of different determined physical and petrophysical parameters and their plots have defined two Flow Zone Indicators (FZI) characterized by a restricted distribution of porosity permeability and rock quality index. Different approval statements were made by correlation process. These confirmation and data support made of the considered reservoir as relative tight reservoir and tight reservoir. The use of the R35 was organized to
make an approval to different statements with reference to the considered reservoir which can be classified as relative tight reservoir and tight reservoir. The R35 was carried out to approve not only that the reservoir is relative tight and tight but it can be classified in the range within the range of nano to microporous system.
This document provides an overview of well log interpretation. It discusses how well logs are used to answer key questions about hydrocarbon-bearing formations like location, quantity, and producibility. The interpretation process involves identifying permeable zones using logs like SP and GR, then using resistivity and porosity logs to locate zones with hydrocarbons. Formations are further evaluated to determine porosity, fluid saturations, and other properties through techniques like density-neutron crossplots, environmental corrections, and determining formation temperature based on geothermal gradient. The goal is to locate potential producing zones and estimate hydrocarbon quantities and recoverability.
This paper discusses an integrated approach to characterizing water saturation in a low-resistivity carbonate reservoir in Abu Dhabi. Traditional resistivity-based analyses overestimated water saturation in this reservoir. The integrated approach combined resistivity logs, core analysis including NMR and capillary pressure tests, and production test data. It identified microporosity from thin sections and NMR as contributing to the low resistivity pay. The combination of multiple data sources reduced uncertainty and improved understanding of reservoir properties, saturation estimates, and reserves calculations compared to resistivity-based analyses alone.
Advances in Rock Physics Modelling and Improved Estimation of CO2 Saturation, Giorgos Papageorgiou - Geophysical Modelling for CO2 Storage, Leeds, 3 November 2015
This document discusses modeling groyne placement on river bends based on sedimentation analysis using numerical simulation with the finite difference method. The goal is to determine optimal groyne placement by considering sediment accumulation volumes in groyne fields.
The study plans to simulate 450 cases combining various groyne positions, lengths, flow velocities, bend radii, and suspended sediment concentrations. Conservation equations for mass and momentum will be used to develop the mathematical model. Validation and verification processes will evaluate the agreement between experimental data and model predictions.
Regression analysis of simulation results will determine suitability coefficients to obtain relationships between parameters like Froude number and groyne length, providing guidance on best distances between groynes. The numerical model aims
This document describes a Runge-Kutta Discontinuous Galerkin method for approximating the shallow water equations. The method introduces two techniques: 1) a flux modification technique to derive a well-balanced scheme that preserves steady states at rest with variable bathymetry, and 2) a slope modification technique to properly handle flooding and drying of water. Numerical results are presented to illustrate the performance of the proposed scheme.
Effect of Height and Surface Roughness of a Broad Crested Weir on the Dischar...RafidAlboresha
Weir is usually incorporated as control or regulation devices in hydraulic systems,
with flow measurement as their secondary. It is normally intended for use in the field and thus
to regulate broad discharges. Broad-Crested weir is among the oldest common weir types. In this
paper, the effect of height and surface roughness for different Board Crested weirs models were
studied on discharge coefficient (Cd) in a horizontal open channel. In the crest of the weir,
certain materials may be combined with concrete (e.g., boulders) or may be used as cladding to
minimize the effect of water overflow (e.g. stone). The weir surface should not be considered
smooth in this case, and the discharge coefficient (Cd) must be re-estimated. For these purposes, laboratory flume was used to study the effect of height and surface roughness on the discharge coefficients with four of the different weir models dimensions of the concrete blocks. In this study, the flow conditions were considered to be free water flow and the viscosity effect was neglected. In all cases, the weir height effect was directly proportional to the discharge coefficient while the surface roughness effect was found to be inversely proportional to the coefficient Cd of the case study.
Pore scale dynamics and the interpretation of flow processes - Martin Blunt, Imperial College London, at UKCCSRC specialist meeting Flow and Transport for CO2 Storage, 29-30 October 2015
The document discusses assessing relative permeabilities in geothermal reservoirs through analyzing the effect of gravity on relative permeabilities, performing laboratory measurements using real geothermal fluids, and calculating relative permeabilities from field data at several geothermal fields in Iceland. The results showed differences in relative permeabilities with flow direction and magnitude, and that wells within the same field can follow different relative permeability curves. Comparisons were made between laboratory and field measurements.
Measuring Hydrualic Conductivity Using Petro Physical Measurements 2013 compa...Christopher Estevez
This summary provides the key points from the document in 3 sentences:
The document discusses various methods for measuring hydraulic conductivity in soils more accurately in the field, including using gravitational methods for saturated soils and the Proportional Cylinder and Arya-Dierolf models for unsaturated soils. It analyzes modifying Darcy's law to account for centrifugal force when measuring saturated soils and how the Proportional Cylinder and Arya-Dierolf models can help determine unsaturated pore size and estimate hydraulic conductivity. Accurately measuring hydraulic conductivity is important for environmental cleanup efforts to more efficiently remove contaminants from lands.
1) The document discusses assessing uncertainty in time-lapse seismic response due to geomechanical deformation.
2) It presents a multi-physics solution that couples fluid flow and geomechanics modeling to better understand stress changes over time.
3) An example application to the Valhall oil field models pore pressure changes and resulting geomechanical effects, partitioning the domain for parallel modeling of the overburden, reservoir, and underburden.
This document summarizes a study on predicting the post-breakthrough performance of simultaneous water and gas coning in horizontal wells. A reservoir model was created using reservoir simulation software to model an oil zone between a gas cap and aquifer. Sensitivity analysis was performed by varying reservoir and fluid parameters to determine which most influence coning behavior. Correlations were developed using regression analysis to predict breakthrough time, gas-oil ratio (GOR), and water-oil ratio (WOR) based on the height of the oil column above and below perforations. The correlations can be used to estimate post-breakthrough performance in horizontal wells experiencing simultaneous water and gas coning.
Passive seismic monitoring for CO2 storage sites - Anna Stork, University of Bristol at UKCCSRC specialist meeting Geophysical modelling for CO2 storage, monitoring and appraisal, 3 November 2015
2014 a method for evaluation of water flooding performance in fractured res...AliMukhtar24
This document presents a new mathematical model for evaluating water flooding performance in fractured reservoirs. The model transforms a dual-porosity reservoir into an equivalent single-porosity model using a pseudo relative permeability method. This allows fractures and matrix to each have their own permeability, porosity, saturation, and relative permeability parameters. The model also accounts for imbibition effects by modifying an existing equation. The investigation shows imbibition can impact recovery and lower production rates can improve water flooding by delaying breakthrough and controlling water cut rise. A new chart is proposed to estimate ultimate recovery based on water cut versus recovery curves. The model is shown to estimate recovery within 2% of simulation results for two reservoirs, proving it a reliable evaluation method.
1) The document analytically solves the nonisothermal Buckley-Leverett problem for two-phase immiscible flow in porous media including a tracer component and temperature effects.
2) Mass balances for the fluids and tracer and a convective heat balance equation are formulated and solved using the method of characteristics.
3) The solutions can be used to analyze pressure transients, interpret formation testing, calculate temperature front propagation during waterflooding, and benchmark simulators.
The detectability of free-phase migrating CO2Rami Eid
1) The document investigates the detectability of migrating carbon dioxide (CO2) using rock physics and seismic modeling of a theoretical sandstone reservoir.
2) Three fluid saturation distribution models were assessed to capture a range of possible seismic responses: uniform, patchy, and modified patchy saturation.
3) Results show the fluid distribution model and relative permeability-capillary pressure curves significantly impact the detectability of migrating CO2, with patchy distributions and site-specific curves yielding lower detectability.
Modelling Fault Reactivation, Induced Seismicity, and Leakage During Underground CO2 Injection, Jonny Rutquvist - Geophysical Modelling for CO2 Storage, Leeds, 3 November 2015
1. The document discusses applying multi-curve reconstruction technology to seismic inversion to improve accuracy and reliability. It focuses on reconstructing SP and RMN curves from well logs that are affected by various distortions.
2. The process of reconstructing the curves involves removing baseline drift, standardizing values, applying linear filtering, and fitting the curves. This removes interference and retains valid lithological information.
3. Reconstructing high quality curves improves the resolution and credibility of seismic inversion results. The method is shown to effectively predict sand distribution with little error.
This document provides an introduction to enhanced oil recovery (EOR) techniques using carbon dioxide injection in a heterogeneous reservoir. It discusses primary, secondary, and tertiary recovery methods and explains that EOR processes are now commonly classified based on the recovery method rather than chronological stage. The document will analyze CO2 injection as a tertiary method to improve oil recovery from a reservoir with heterogeneity, using reservoir simulation and case studies.
K.E. Al-Khidir, M.S. Benzagouta
Department of Petroleum Engineering and Natural Gas, College of Engineering,
King Saud University, Saudi Arabia
К.Е. Аль-Хидир, М.С. Бензагута
Инженерный колледж, Университет короля Сауда
Abstract. With reference to the reservoir characterization regarding the Khuff Formation – Khurtam Member (KSA), better reservoir quality prediction can be assigned to
the characterization of its physical properties. These properties determination are depending on facies description. These properties can be erratic according to the diagenetic change and control on pore geometrical attributes and reservoir characterization. In this
investigation, permeability and porosity have been measured in the laboratory. Rock Quality Index (RQI), flow zone index (FZI) as well as porosity groups have been
calculated. The use of different determined physical and petrophysical parameters and their plots have defined two Flow Zone Indicators (FZI) characterized by a restricted distribution of porosity permeability and rock quality index. Different approval statements were made by correlation process. These confirmation and data support made of the considered reservoir as relative tight reservoir and tight reservoir. The use of the R35 was organized to
make an approval to different statements with reference to the considered reservoir which can be classified as relative tight reservoir and tight reservoir. The R35 was carried out to approve not only that the reservoir is relative tight and tight but it can be classified in the range within the range of nano to microporous system.
This document provides an overview of well log interpretation. It discusses how well logs are used to answer key questions about hydrocarbon-bearing formations like location, quantity, and producibility. The interpretation process involves identifying permeable zones using logs like SP and GR, then using resistivity and porosity logs to locate zones with hydrocarbons. Formations are further evaluated to determine porosity, fluid saturations, and other properties through techniques like density-neutron crossplots, environmental corrections, and determining formation temperature based on geothermal gradient. The goal is to locate potential producing zones and estimate hydrocarbon quantities and recoverability.
This paper discusses an integrated approach to characterizing water saturation in a low-resistivity carbonate reservoir in Abu Dhabi. Traditional resistivity-based analyses overestimated water saturation in this reservoir. The integrated approach combined resistivity logs, core analysis including NMR and capillary pressure tests, and production test data. It identified microporosity from thin sections and NMR as contributing to the low resistivity pay. The combination of multiple data sources reduced uncertainty and improved understanding of reservoir properties, saturation estimates, and reserves calculations compared to resistivity-based analyses alone.
Similar to Pressure head fractal dimension for characterizing shajara reservoirs of the shajara formation of the permo carboniferous unayzah group, saudi arabia
This document summarizes the analysis of petrophysical data from two wells in the Upper Spraberry Formation to develop a rock-fluid model. Six distinct rock types were identified based on unique pore geometry, mineral composition, and fluid flow characteristics. Laboratory analysis of core plugs using nitrogen, helium, and mercury injection characterized porosity, permeability, pore size distribution, and wettability of each rock type. Clean sandy rocks generally had higher porosity and permeability than shaly or dolostone units. Integration of petrophysical data with log responses and core descriptions allowed differentiation of reservoir-quality from lower-quality rock intervals in the formation.
Number of moles fractal dimensions for characterizing shajara reservoirs of t...Khalid Al-Khidir
This document summarizes a research article that calculates fractal dimensions from the relationship between number of moles, maximum number of moles, and wetting phase saturation in sandstone samples from the Shajara Formation in Saudi Arabia. Porosity was measured on samples and permeability was derived from capillary pressure data. Two equations were used to calculate fractal dimensions from number of moles and from capillary pressure relationships. Results showed similarity between the two fractal dimensions. Samples with a wide range of pore radii had higher fractal dimensions, reflecting greater connectivity and ability to accommodate more moles. The formation was divided into three reservoir units based on fractal dimensions. Higher fractal dimensions indicated higher heterogeneity and permeability, characterizing better reservoirs
The New Capillary Number Parameterization for Simulation in Surfactant FloodingPremier Publishers
The Capillary number hypothesis is very empirical in Surfactant flooding Enhanced Oil Recovery (EOR) method. which is of modest experience on the North Sea and many other offshore platforms. The capillary number drives the force wetting processes, which is controlled by the balance between capillary and viscous forces. The mobilization of oil trapped in pores of water-wet rock is steered by capillary number that is typically within specific ranges (〖10〗^(-5) to〖 10〗^(-4)). There is high uncertainty and confusion in the parameterization of capillary number formula, as every quantity is given on a macroscale level. As demonstrated herein, a new microscopic capillary number parameterization was proposed. This paper is written to improve the numerical formulation of capillary number in surfactant flooding model. The new formula for capillary number was derived based on existing equations as a function of residual oil saturation and tested. Thus, the proposed mobility mechanism easily accounts for a broader critical range of capillary number (〖10〗^(-6) to〖 10〗^(-4)) in comparison with available models with a critical capillary number (〖10〗^(-5) to〖 10〗^(-4)). We used an existing model to quantify the effect of capillary number on a miscible and immiscible relative permeability curves by computing the interpolation parameter F_kr as a tabulated function of the Logarithm (base 10) of the capillary number using a new capillary number formulation.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
1. The document presents a pressure transient analysis method for a reservoir with an internal circular boundary, such as a gas cap.
2. The problem is modeled using the Laplace transform solution of the diffusivity equation with boundary conditions. This allows developing a generalized type curve solution.
3. A new generalized type curve is presented, which allows estimating the permeability of the reservoir section within the boundary and the transient time to reach the boundary through type curve matching, without using the double straight line technique.
The document describes a numerical study of two-phase flows in a model ladle containing molten metal agitated by nitrogen gas injection. An Eulerian-Eulerian model is used to simulate the gas and liquid phases. Different drag and lift force coefficients are examined and compared to experimental data on liquid velocity, bubble velocity, and gas volume fraction. Results show reasonable agreement with experiments in the liquid region but larger deviations in the gas-liquid plume region. An improved drag coefficient correlation is proposed.
This document presents a case study of formation evaluation of two wells from the Mehsana Field in India. Logs from one well are analyzed to identify different zones and compare the classical Archie and Indonesian equations for calculating water saturation in shaly sands. The Indonesian equation, which accounts for clay volume, is found to provide more accurate estimates of water saturation compared to the Archie equation. Crossplots of various well log properties are also effective in evaluating shaly reservoirs and determining parameters like water resistivity and cementation exponent. The study demonstrates the challenges of evaluating shaly sands and importance of using appropriate models and crossplots.
The document discusses five different rock typing methods commonly used for carbonate reservoirs: Hydraulic Flow Unit (HFU), Global Hydraulic Element (GHE), Pore Geometry Structure (PGS), Jennings-Lucia, and Winland R35. It analyzes these methods by applying them to core data from the Minahaki Formation and comparing the resulting rock types using Leverett J-Functions. The HFU, GHE, and PGS methods group rock types based on integration of geological and petrophysical parameters, while the others focus more on petrophysical properties. The analysis finds that the most consistent method for this reservoir is one that integrates both geological description and engineering hydraulic features.
This document summarizes a study that evaluated liquefaction potential in Babol City, Iran using both deterministic and probabilistic approaches. Over 600 soil borehole records from 60 sites were analyzed using 4 deterministic methods (including Seed) and 1 probabilistic reliability method. Microzonation maps identified liquefaction and non-liquefaction areas for each method. Results showed the reliability approach provided an accurate assessment of liquefaction potential. A 2D boundary line was also developed using (CSR) and (Nspt) parameters to identify liquefaction/non-liquefaction areas based on safety factors and probability. The study aims to assess liquefaction potential in Babol City and determine the most valid approach.
Naghizadehrokni et al-2018-geoenvironmental_disastersMehran Naghizadeh
This document summarizes a study that evaluated liquefaction potential in Babol City, Iran using both deterministic and probabilistic approaches. Over 600 soil borehole records from 60 sites across the city were analyzed using 4 deterministic methods (including Seed's method) and 1 probabilistic reliability method. Microzonation maps showed liquefaction and non-liquefaction areas from each method. The reliability approach was found to accurately assess liquefaction potential. A 2D boundary line was also developed from the data to identify liquefaction/non-liquefaction based on cyclic stress ratio and SPT resistance. The maps and boundary line produced can help identify liquefaction risk in Babol City.
On the equality of electric power fractal dimension and capillary pressure fr...Khalid Al-Khidir
On the equality of electric power fractal dimension and capillary pressure fractal dimension for characterizing shajara reservoirs of the permo carboniferous shajara formation
Effect of Geometry on Variation of Heat Flux and Drag for Launch Vehicle -- Z...Abhishek Jain
Above Research Paper can be downloaded from www.zeusnumerix.com
The research paper aims at studying the variation of the geometry of the launch vehicle nose and its effect on heat flux. CFDExpert software is first validated on NASA's hyperballistic model and then used on proposed geometries. Various nose radius and blending shapes are studied for effect on drag and heat flux. Cone ogive shape is found to decrease heat flux with an insignificant increase in drag. Authors Abhishek Jain (Zeus Numerix), Rohan Kedar and Prof V Kalamkar (SPCOE).
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Pressure head fractal dimension for characterizing shajara reservoirs of the shajara formation of the permo carboniferous unayzah group, saudi arabia
1. 1 Volume 2017; Issue 02
Archives of Petroleum & Environmental
Biotechnology
Research Article
Al-Khidir KE. Arch Pet Environ Biotechnol: APEB -113.
Pressure Head Fractal Dimension for Characterizing Shajara
Reservoirs of the Shajara Formation of the Permo-Carbonifer-
ous Unayzah Group, Saudi Arabia
Khalid Elyas Mohamed Elamin AlKhidir*
Department of Petroleum Engineering and Natural Gas, King Saud University, Saudi Arabia
*
Corresponding author: Khalid Elyas Mohamed Elamin AlKhidir, Department of Petroleum Engineering and Natural Gas, Col-
lege of Engineering, King Saud University, Riyadh, Saudi Arabia. Tel: +96611 4679118; Email: kalkhidir@ksu.edu.sa
Citation: Al-Khidir KEME (2017) Pressure Head Fractal Dimension for Characterizing Shajara Reservoirs of the Shajara Forma-
tion of the Permo-Carboniferous Unayzagh Group, Saudi Arabia. Arch Pet Environ Biotechnol: APEB -113.
Received Date: 27 June, 2017; Accepted Date: 13 July, 2017; Published Date: 20 July, 2017
Abstract
Pressure head was gained from distribution of pores to characterize the sandstones of the Shajara reservoirs of the Shajara
Formation of the Permo-Carboniferous Unayzah Group. The attained values of pressure head were employed to calculate the
pressure head fractal dimension. Based on field observations in addition to the acquired values of pressure head fractal dimen-
sion, the sandstones of Shajara reservoirs were divided here into three units. The obtained units from base to top are: Lower
Shajara Pressure Head Fractal Dimension Unit, Middle Shajara Pressure Head Fractal Dimension Unit and Upper Shajara Pres-
sure Head Fractal Dimension Unit.
The three Shajara reservoirs were also confirmed by the ratio of bubble pressure to capillary pressure at other points versus
effective saturation. It was reported that the permeability accelerates with increasing bubble pressure fractal dimension due to
the naturally occurring interconnected channels. The pressure head fractal dimension and bubble pressure fractal dimension was
successfully characterize the sandstones of the Shajara reservoirs with certain degree of accuracy.
Introduction
Capillary pressure is generally expressed as an aspect of the
wetting phase saturation, according to the capillary pressure mod-
el [1]. The capillary pressure function was modified by Brooks and
Corey (1964) [2] by applying a pore size distribution index (λ) as
an exponent on the ratio of bubble pressure to capillary pressure.
According to their results, a linear relationship exists between pres-
sure and effective saturation on a log-log plot. This mathematical
relationship has been named the Brooks-Corey model (B-C mod-
el). A model that predicts the hydraulic conductivity for un- satu-
rated soil-water retention curve and conductivity saturation was
derived by Mualem (1976) [3]. Later, based on Mualem’s formula,
Van Genuchten (1980) [4] described a relatively simple expression
for the hydraulic conductivity of unsaturated soils. The Van Genu-
chten model (V-G model) contained three independent parameters,
which can be obtained by fitting experimental data. A function to
estimate the relationship between water saturation and capillary
pressure in porous media was proposed by Oostrom and Len-
hard (1998) [5]. This function is test data of sandstone rocks and
carbonate rocks with high permeability were described by a new
capillary pressure expression by Jing and Van Wunnik (1998) [6].
A fractal approach can be used to model the pc measured
with mercury intrusion in Geysers grey wackerock; however, the
B-C model could not be used, according to a study by Li (2004)
[7]. Sub-sequently, a theoretical analysis using fractal geometry
was conducted by Li and Horne (2006) [8] to deduce the B-C
model, which has always been considered as an empirical model.
Subsequently, fractal modeling of porous media was used to de-
velop a more generalized capillary pressure model (Li, 2010a) [9].
With the new model, he also evaluated the heterogeneity of rocks
2. Citation: Al-Khidir KEME (2017) Pressure Head Fractal Dimension for Characterizing Shajara Reservoirs of the Shajara Formation of the Permo-Carboniferous Unayz-
agh Group, Saudi Arabia. Arch Pet Environ Biotechnol: APEB -113.
2 Volume 2017; Issue 02
(Li, 2010b) [10]. Al-Khidir, et al. 2011 [11] studied Bimodal Pore
Size behavior of the Shajara Formation reservoirs of the permo-
carboniferous Unayzah group. Al-Khidir, et al. (2012) [12] sub-
divided the Shajara reservoirs into three units based on thermody-
namic fractal dimension approach and 3-D fractal geometry model
of mercury intrusion technique. The work published by Al-Khidir,
et al. 2012 was cited as Geoscience; New Finding reported from
King Saud University Describe advances in Geoscience. Science
Letter (Oct 25, 2013): 359. Al-khidir, et al. 2013 [13,14] subdivide
the Shajara reservoirs into three units: Lower Shajara Differen-
tial Capacity Fractal Dimension Unit, Middle Shajara Differential
Capacity Fractal Dimension Unit, Upper Shajara Differential Ca-
pacity Fractal Dimension Unit. The Three reservoirs units were
confirmed by water saturation fractal dimension. Al-Khidir 2015
[15] subdivided the Shajara reservoirs into three induced polariza-
tion geometric time fractal dimension units and confirmed them by
arithmetic relaxation time fractal dimension of induced polariza-
tion.
Materials and Methods
The purpose of this paper is to obtain pressure head frac-
tal dimension (Dαh) and to confirm it by bubble pressure fractal
dimension (DP/pc). The pressure head fractal dimension is deter-
mined from the slope of the plot of effective wetting phase satura-
tion (Se) versus pressure head (α*h). The exponent on the pressure
head relates to the fitting parameters m*n which match with the
pore size distribution index (λ). The bubble pressure fractal dimen-
sion was obtained from the slope of the plot of wetting phase effec-
tive saturation (Se) versus the plot of the ratio of bubbling pressure
(Pb) to capillary pressure (pc). The slope of the functional relation-
ships among capillary pressure and effective saturation correspond
to the pore size distribution index (λ). Theoretically, the pore size
distribution index being small for media having a wide range of
pore sizes and large for media with a relatively uniform pore size.
Field Data: Sandstone samples were collected from the type sec-
tion of the Shajara Formation of the Permo-Carboniferous Unayz-
ah Group, Wadi Shajara, Qusayba area, al Qassim district, Saudi
Arabia, N 2652 17.4, E 4336 18. (Figure1). Porosity was measured
on collected samples using mercury intrusion Porosimetry and
permeability was derived from capillary pressure data.
Symbols: Φ porosity in percent, K permeability in millidarcy, λ
pore size distribution index, m, n, are fitting parameter, Pb bubble
pressure in psi, pc capillary pressure in psi, α inverse of pressure
head in cm, h is the pressure head in cm, Dp/pc. Bubble pressure
fractal dimension, Dαh pressure head fractal dimension, Se effec-
tive wetting phase saturation.
Results
The obtained results of the log log plot of the ratio of bubble
pressure (Pb) to pressure (p) and the product of inverse pressure
head (α) and pressure head (h) versus effective wetting phase satu-
ration (Se) are shown in (Figures 2: Figure 11). A straight line was
attained whose slope is equal to the pore size distribution index
(λ) of Brooks and Corey (1964) [2] and the fitting parameters m
times n of Van Genuchten (1980) [4] respectively. Based on the
acquired results it was found that the pore size distribution index
is equal to the fitting parameters m*n. The maximum value of the
pore size distribution index was found to be 0.4761 assigned to
sample SJ5 from the Lower Shajara Reservoir (Table 1). Whereas
the minimum value of the pore size distribution index was reported
from sample SJ13 from the Upper Shajara reservoir (Table 1). The
pore size distribution index and the fitting parameters m*n were
observed to decrease with increasing permeability (Table 1) owing
to the possibility of having interconnected channels. The bubble
pressure fractal dimension and pressure head fractal dimension
which were derived from the pore size index were noticed to in-
crease with increasing permeability and show similarity in their
values (Table 1). Based on field observation the Shajara Reservoirs
of the Shajara Formation of the Permo-Carboniferous Unayzah
Group were divided into three units (Figure 1).
3. Citation: Al-Khidir KEME (2017) Pressure Head Fractal Dimension for Characterizing Shajara Reservoirs of the Shajara Formation of the Permo-Carboniferous Unayz-
agh Group, Saudi Arabia. Arch Pet Environ Biotechnol: APEB -113.
3 Volume 2017; Issue 02
Figure 1: Stratigraphic column of the type section of the Permo-Carboniferous Shajara Formation of the Unayzah Group, Wadi Shajara, Qusayba area,
al Qassim district, Saudi Arabia, N 2652 17.4, E 4336 18.
4. Citation: Al-Khidir KEME (2017) Pressure Head Fractal Dimension for Characterizing Shajara Reservoirs of the Shajara Formation of the Permo-Carboniferous Unayz-
agh Group, Saudi Arabia. Arch Pet Environ Biotechnol: APEB -113.
4 Volume 2017; Issue 02
These units from base to top are: Lower Shajara Reservoir, Middle Shajara reservoir, and Upper Shajara Reservoir. The Lower
Shajara reservoir was represented by four sandstone samples out of six, namely SJ1, SJ2, SJ3 and SJ4.Sample SJ1 is described as
medium-grained, porous, permeable, and moderately well sorted red sandstone (Figure 1). Its pore size distribution index and fitting
parameter m*n show similar values (Figure 2 and Table 1)
Figure 2: Log (Pb/pc) versus log Se in red color and Log (α*h) versus log Se in blue Color.
Reservoirs Sample Φ (%) k (md) λ m*n m n Dp/pc Dαh
Lower
Shajara
Reservoir
SJ1 29 1680 0.2141 0.2141 0.176345 1.2141 2.7859 2.7859
SJ2 35 1955 0.2252 0.2252 0.183807 1.2252 2.7748 2.7748
SJ3 34 56 0.5621 0.5621 0.359836 1.5621 2.4379 2.4379
SJ4 30 176 0.3157 0.3157 0.239948 1.3157 2.6843 2.6843
Middle
Shajara
Reservoir
SJ7 35 1472 0.2317 0.2317 0.188114 1.2317 2.7683 2.7683
SJ8 32 1344 0.2248 0.2248 0.18354 1.2248 2.7752 2.7752
SJ9 31 1394 0.2214 0.2214 0.181267 1.2214 2.7786 2.7786
Upper
Shajara
Reservoir
SJ11 36 1197 0.2414 0.2414 0.194458 1.2414 2.7586 2.7586
SJ12 28 1440 0.2141 0.2141 0.176345 1.2141 2.7859 2.7859
SJ13 25 973 0.2128 0.2128 0.175462 1.2128 2.7872 2.7872
Table 1: Petrophysical properties characterizing Shajara reservoirs of the Shajara Formation of the Permo-Carboniferous Unayzah Group.
Its bubble pressure fractal dimension and pressure head fractal dimension which was derived from pore size distribution index
and the fitting parameter m*n respectively also indicates similar values (Table 1). (Figure 3) delineates straight line plot of log (Pb/p)
versus log effective saturation, and log (α*h) versus log effective saturation of sample SJ2 which is defined as medium - grained, porous,
permeable, well sorted, yellow sandstone (Figure 1). It acquired a pore size distribution index of about 0.2252 whose value equal to m*n
(Figure 3).
Figure 3: Log (Pb/pc) versus log Se in red color and log (α*h) versus log Se in blue color.
5. Citation: Al-Khidir KEME (2017) Pressure Head Fractal Dimension for Characterizing Shajara Reservoirs of the Shajara Formation of the Permo-Carboniferous Unayz-
agh Group, Saudi Arabia. Arch Pet Environ Biotechnol: APEB -113.
5 Volume 2017; Issue 02
Figure 4: Log (Pb/pc) versus log Se in red color and log (α*h) versus log
Se in blue.
Figure 5: Log (Pb/pc) versus log Se in red color and log (α*h) versus log
Se in blue Color.
It is also characterized by similarity in bubble pressure frac-
tal dimension and pressure head fractal dimension as displayed in
(Table 1). As we proceed from sample SJ2 to SJ3 a pronounced re-
duction in permeability due to compaction was reported from 1955
md to 56 md which reflects an increase in pore size distribution
index from0.2252 to 0.5621 and reduction in fractal dimension
from 2.7748 to 2.4379 as stated in (Table 1). Again, an increase in
grain size and permeability was recorded from sample SJ4 which
is characterized by 0.3157 pore size distribution index and 2.6843
bubble pressure fractal dimension which agree with the pressure
head fractal dimension (Table 1). In contrast, the Middle Shajara
reservoir which is separated from the Lower Shajara reservoir by
an unconformity surface (Figure 1) was designated by three sam-
ples out of four, namely SJ7, SJ8, and SJ9 as illustrated in (Figure
1). Their pore size distribution index and fitting parameters m*n
were reported in (Figures 6, 7, 8, and Table 1).
Figure 6: Log (Pb/pc) versus log Se in red color and log (α*h) versus log
Se in blue.
Figure 7: Log (Pb/pc) versus log Se in red color and log (α*h) versus log
Se in blue color.
Figure 8: Log (Pb/pc) versus log Se in red color and log (α*h) versus log
Se in blue Color.
Their bubble pressure fractal dimensions and pressure head
fractal dimensions are higher than those of samples SJ3 and SJ4
from the Lower Shajara Reservoir due to an increase in their per-
meability (Table 1). On the other hand, the Upper Shajara reservoir
6. Citation: Al-Khidir KEME (2017) Pressure Head Fractal Dimension for Characterizing Shajara Reservoirs of the Shajara Formation of the Permo-Carboniferous Unayz-
agh Group, Saudi Arabia. Arch Pet Environ Biotechnol: APEB -113.
6 Volume 2017; Issue 02
is separated from the Middle Shajara reservoir by yellow green
mudstone as demonstrated in (Figure 1). It is defined by three sam-
ples so called SJ11, SJ12, SJ13 as explained in (Figure 1). Further-
more, their pore size distribution index and the fitting parameters
m*n were demonstrated in (Figure 9,10,11, and Table 1).
Figure 9: Log (Pb/pc) versus log Se in red color and log (α*h) versus log
Se in blue Color.
Figure 10: Log (Pb/pc) versus log Se in red color and log (α*h) versus log
Se in blue Color.
Figure 11: Log (Pb/pc) versus log Se in red color and log (α*h) versus
log Se in blue Color.
Moreover, their bubble pressure fractal dimension and pres-
sure head fractal dimension are also higher than those of sample
SJ3 and SJ4 from the Lower Shajara Reservoir due to an increase
in their flow capacity (permeability) as explained in (Table 1).
Overall a plot of pore size distribution index and the fitting param-
eter n versus fractal dimension (Figure 12) reveals three perme-
able zones of varying Petrophysical properties. The higher fractal
dimension zone with fractal dimension higher than 2.75 (Figure
12) corresponds to the full Upper Shajara Reservoir, entire Middle
Shajara Reservoir and Sample SJ1 and SJ2 from the lower Shajara
Reservoir. The middle fractal dimension zone with a value of about
2.68 (Figure12) resembles sample SJ4 from the lower Shajara res-
ervoir.
Figure 12: Pore size distribution index (λ) in red color and fitting param-
eter (n) in blue color versus fractal Dimension (D).
The lower fractal dimension value2.43 allocates to sample
SJ3 from the Lower Shajara reservoir as shown in (Figure 12). The
three Shajara fractal dimension zones were also confirmed by plot-
ting pressure head fractal dimension versus bubble pressure fractal
dimension as illustrated in (Figure 13).
Figure 13: Pressure head fractal dimension (Dαh) versus bubble pressure
fractal dimension (DP/pc).
Conclusion
The obtained Shajara bubble pressure fractal dimension res-1.
ervoir units were also confirmed by pressure head fractal di-
mension.
It was found that, the higher the bubble pressure fractal dimen-2.
sion and pressure head fractal dimension, the higher the per-
meability leading to better Shajara reservoir characteristics.
7. Citation: Al-Khidir KEME (2017) Pressure Head Fractal Dimension for Characterizing Shajara Reservoirs of the Shajara Formation of the Permo-Carboniferous Unayz-
agh Group, Saudi Arabia. Arch Pet Environ Biotechnol: APEB -113.
7 Volume 2017; Issue 02
It was also reported that, the bubble pressure fractal dimension3.
and pressure head fractal dimension increases with decreasing
pore size distribution index and fitting parameters m*n owing
to possibility of having interconnected channels.
Digenetic features such as compaction plays an important role4.
in reducing bubble pressure fractal dimension and pressure
head fractal dimension due to reduction in pore connectivity.
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