Emad Jamshidi - Academia.edu (original) (raw)
Papers by Emad Jamshidi
Petroleum Science and Technology, 2011
Results in geophysical sciences, Jun 1, 2023
Research Square (Research Square), Feb 7, 2023
Bullet Points • The tilt angle can lessen the sensitivity to existing noises and induction ones. ... more Bullet Points • The tilt angle can lessen the sensitivity to existing noises and induction ones. • Existing lots of noises can make the detection difficult and lead to blurred boundaries. • Geosoft and ModelVision Pro software are employed to map and model Bouguer and residual anomalies to pinpoint anticline oil traps in the surveyed area. • Turtle-back anticlines are typical structures that develop between facing listric growth faults rooted in a flat-lying decollement that help to find salt dome anticlines.
Geophysical investigations are one of the leading efforts in any exploration project that must be... more Geophysical investigations are one of the leading efforts in any exploration project that must be performed ahead of time due to the high excavation expenditures, heavy machinery, and cost reduction. One of the essential geophysical concerns is the estimation of the physical and geometrical parameters of the reserve (geobody), which is done by exploiting the nonlinear inverse modeling of magnetic data. These parameters include depth, volume, shape factor, and type of storage. The present investigation aims to prepare and model magnetic data for proposed drilling sites in the Baba Ali Iron ore deposit in the Hamedan province of Iran. The areal and depth extent of the iron ore geobody was unknown. The Bhattacharyya method by MATLAB software coding was used to minimize the target function and potential field data and create the best fit for the magnetic data. The residual anomaly and model graphs exhibited an excellent two-dimensional conformation in this modeling. Also, 3D modeling co...
Geophysical investigations are one of the leading efforts in any exploration project that must be... more Geophysical investigations are one of the leading efforts in any exploration project that must be performed ahead of time due to the high excavation expenditures, heavy machinery, and cost reduction. One of the essential geophysical concerns is the estimation of the physical and geometrical parameters of the reserve (geobody), which is done by exploiting the nonlinear inverse modeling of magnetic data. These parameters include depth, volume, shape factor, and type of storage. The present investigation aims to prepare and model magnetic data for proposed drilling sites in the Baba Ali Iron ore deposit in the Hamedan province of Iran. The areal and depth extent of the iron ore geobody was unknown. The Bhattacharyya method by MATLAB software coding was used to minimize the target function and potential field data and create the best fit for the magnetic data. The residual anomaly and model graphs exhibited an excellent two-dimensional conformation in this modeling. Also, 3D modeling co...
The analytical signal method and its derivatives can be explicitly calculated and assessed for an... more The analytical signal method and its derivatives can be explicitly calculated and assessed for analyzing and estimating the boundary of geological structures, such as faults or dikes, from potential field anomalies. Gravity field of the east of Qeshm Island and its north coast from Sarkhun to Latidan in SE Iran has been measured in one-kilometer regular network. The regional anomaly effects are deducted from the Bouguer anomaly, where it can get the residual anomalies which is the considered dataset used in this study. The Bouguer range is -297 to -330 milligals (mGal) applying filters and modeling. It was revealed that there are five negative anomalies caused by salt penetration in the region. Regional anomalies expectedly have a low spatial frequency and long wavelengths, while the residual anomalies associated with shallow sub-surface potentials have high spatial frequencies and short-wave wavelengths. Two different fault trends were observed comparing the artificial model using ...
One of the most critical issues in describing gravitational maps is separating the anomalies rela... more One of the most critical issues in describing gravitational maps is separating the anomalies related to shallow sources from the deep ones. In this study, every kilometer of assessing gravity in a very regular network is done from the shallow part of the west of Qeshm Island to Hormoz and its north coast from Sarkhoun to Latidan in SE Iran. The range of gravitational Bouguer changes is from − 297 to-330 miligal (mGal), which after modeling and determining geometrical parameters, It was found that five negative anomalies came from salt penetration in this region. On the Bouguer anomaly maps, profound effects were seen as light and linear, called regional effects. The residual gravity was computed by removing gravitational effects related to deep sources from measured gravitational data. Regional anomalies have a low spatial frequency and long wavelength, while residual anomalies are related to under-surface potentials and have a high spatial frequency and short wavelength. By compari...
Results in Geophysical Sciences
Enhanced Oil Recovery (EOR) process is used to recover additional oil left in place after primary... more Enhanced Oil Recovery (EOR) process is used to recover additional oil left in place after primary recovery. The prediction of its performanceis of great importance in selection and design ofcertain EOR process and future planning for oil production. Microbial Enhance Oil Recovery(MEOR) is friendly with environment, and it isapplied as ex-situ and in-situ in oil reservoirs. In microbial flooding, in the water oil contact themicroorganisms consume the nutrition and producebioacid, biopolymer, biosurfactant, biogas and solvent, which improve the oil recovery and yield theless harmful product for a green environment with respect to other types of EOR methods. This study was investigated potential of applying MEOR by oilrecovery prediction in five different carbonate reservoirs. The study is conducted utilizing 100 laboratory data with valid references. In all of thesereferences, MEOR processes are obtained based on porosity, permeability, salinity, temperature, pressure and PH. Clostrid...
Gas hydrates are easily formed during the transportation of oil and gas when it contains a certai... more Gas hydrates are easily formed during the transportation of oil and gas when it contains a certain amount of water. This paper describes the development and application of Artificial Neural Networks (ANN) that optimized by imperialist competitive algorithm (ICA) for the prediction of natural gas hydrates formation Temperature. In this work after training so ICA-ANN models we find an optimum one that have been used to accurately simulating carbon dioxide hydrate dissociation Temperature. Hence, reliable data of Co 2 were used as input in obtained ICA-ANN model. The obtained results are in the minimum error in compare to experimental.
Drilling industry encounters various challenges during planning and drilling a new well. There ar... more Drilling industry encounters various challenges during planning and drilling a new well. There are numerous parameters related to drilling operations that are planned and adjusted as drillingadvances. Among them, bit selection is one of the most influential considerations for planning and constructing a new borehole. Conventional bit selections are mostly based on drillers’ experiences in the field or mathematical equations, which standmore on recorded performances of similar bits from offset wells. It is evident that these sophisticated interrelations between parameters never can be stated in a single mathematical equation. In such intricate cases, utilizing virtual intelligence and Artificial Neural Networks (ANNs) is proven to be worthwhilein understanding complex relationships between variables. In this paper, two models are developedwith high competence and utilizing ANNs. The first model provides appropriate drilling bit selection based on desired ROP to be obtained by applyin...
International Petroleum Technology Conference, 2013
Drilling industry encounters various challenges during planning and drilling a new well. There ar... more Drilling industry encounters various challenges during planning and drilling a new well. There are numerous parameters related to drilling operations that are planned and adjusted as drilling advances. Among them, bit selection is one of the most influential considerations for planning and constructing a new borehole. Conventional bit selections are mostly based on drillers' experiences in the field or mathematical equations which stand more on recorded performances of similar bits from offset wells. It is evident that these sophisticated interrelations between parameters never can be stated in a single mathematical equation. In such intricate cases, utilizing virtual intelligence and Artificial Neural Networks (ANNs) is proven to be worthwhile in understanding complex relationships between variables. In this paper, two models are developed with high competence and utilizing ANNs. The first model provides appropriate drilling bit selection based on desired ROP to be obtained by applying specific drilling parameters. The second model uses proper drilling parameters obtained from optimizing procedure to select drilling bit which provides maximum achievable ROP. Meanwhile, Genetic Algorithm (GA), as a class of optimizing methods for complex functions, is applied. The proposed methods assess the current conditions of drilling system to optimize the effectiveness of drilling, while reducing the probability of early wear of the drill bit. The correlation coefficients for predicted bit types and optimum drilling parameters in testing the obtained networks are 0.95 and 0.90, respectively. The proposed methodology opens new opportunities for real-time and in-field drilling optimization that can be efficiently implemented within the span of the existing drilling practice.
Petroleum Science and Technology, 2011
The advanced technology has made directional drilling widely applicable in the drilling industry ... more The advanced technology has made directional drilling widely applicable in the drilling industry for different purposes. The trajectory of a directional well is such that it hits the desired target, typically located away from the surface location of the well, at a specified depth and angle. The well trajectory's azimuth and inclination have very obvious and important effects on the directional drilling performance. The aim of this study is to optimize the trajectory of the well to achieve maximum rate of penetration (ROP) as well as maximum possible wellbore stability. To achieve this, a model that predicts the ROP in a directional well is developed using artificial neural networks (ANNs) based on the 15 input parameters. In the modeling, in addition to the azimuth and angle of the well trajectory, drilling operation parameters and principal stresses of the region are included as inputs. The optimizing process is then performed to achieve the maximum rate of penetration to propose the related azimuth and angle of trajectory. Finally, the provided well trajectory is checked to examine the stability of the wellbore. As the final result a well trajectory that provides the maximum rate of penetration as well as the best stability of the wellbore is designed and proposed. This work also considers the properties of different formations existing in the well path, controlling the direction to hit the desired target at the specified depth.
Petroleum Science and Technology, 2011
... to take advantage of ANN modeling to predict the UCS profile by applying drilling parameters ... more ... to take advantage of ANN modeling to predict the UCS profile by applying drilling parameters ... when sufficient sets of inputs and outputs of that function exist is well understood and ... Recent development in application of artificial intelligence in petroleum engineering SPE Paper No ...
Petroleum Science and Technology, 2014
ABSTRACT Wellbore instability, which is considered as failure of borehole wall, is a complex and ... more ABSTRACT Wellbore instability, which is considered as failure of borehole wall, is a complex and time-consuming analysis. Numerous factors such as well path, rock mechanical properties, in situ stress regimes, pore pressure, mud weight, bedding planes, and fractures play a role in borehole instability. Many wellbore stability analyses methods consider only a few of mentioned parameters and majority of them are based on continuum mechanics. However, most of the methods presented for wellbore stability analyses do not consider the impact of fractures. In the present work discrete element models (DEM) are used for numerical wellbore stability analysis of horizontal wells, while the presence of fractures is considered. In this study the effect of mud cyclic loading, hole length, stress regimes, and fluid pressures in fracture plane are examined. The results of analyses showed that direction of minimum horizontal stress is the optimum drilling direction. To evaluate the effects of mud cyclic loadings and open hole lengths, two other models are also considered. These models reveal that mud cyclic loading reduces the stability of borehole. Moreover, it was concluded that mud weight must be increased as open hole length increases and it should not exceed the upper mud weight limit.
Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2012
Tight gas reservoirs are categorized as unconventional gas reservoirs. One of the main characteri... more Tight gas reservoirs are categorized as unconventional gas reservoirs. One of the main characteristics of a tight gas reservoir is the adsorption of gas on the rock surface due to high specific surface area. Desorption is the process of adsorbing gas by the reservoir rock on its surface that is dependent on factors, such as reservoir pressure, reservoir rock type,
Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2013
ABSTRACT Understanding the mechanical properties of formations has its importance in the drilling... more ABSTRACT Understanding the mechanical properties of formations has its importance in the drilling, production, and management phases of reservoirs. In petroleum engineering, measurements through wire-line logs, which run in the boreholes after the drilling phase, are of the most common methods to estimate mechanical properties of different layers. Elastic rock mechanic measurements from logs are dynamic values and need to be upscaled and calibrated to fit the corresponding pseudo-static measurements that are obtained from cores in the laboratory. As a practical approach to having a continuous profile of these static parameters and surmount the arduousness that confronts by using core samples and laboratory tests, many researchers tried to deploy predictive methods and empirical correlations. However, it will be a great advantage to have a real-time estimation of these static parameters while drilling based on bit and formation rock interaction. Artificial neural networks are powerful tools for estimation of complex functions subjected to availability of large enough data sets that present samples of actual behavior of the function. In this study, artificial neural networks were implemented to estimate in situ rock mechanical properties, including Unconfined Compressive Strength, Young's Modulus of Elasticity, and the ratio of these parameters known as Modulus Ratio, by using operational drilling parameters as inputs. Required data were gathered from drilling reports, logging operations, and core samples from nine wells placed in Ahwaz Oilfield located in south-west Iran. The trained networks showed satisfactory low errors in the testing process and sketched the capability of artificial neural networks in estimation of complex functions. The accuracy of the presented model was then compared with the results of calibrated regional correlations and modified Warren's equation. These correlations are used in the candidate wells to estimate Unconfined Compressive Strength and Young's Modulus of Elasticity. It was observed that the new artificial neural network approach is a competent and accurate method for real-time calculation of static elastic properties of formation rocks. The results of this work could be used for drilling optimization, reducing stability problems, and lithologic boundary detection while drilling.
Elsevier, 2023
Noise cancelation is the process done to remove out-of-range anomalies and make better edge bound... more Noise cancelation is the process done to remove out-of-range anomalies and make better edge boundaries interpretation. One of the most challenging issues in describing gravitational maps is separating the anomalies related to shallow sources from the deep ones. Furthermore, Existing noises can make it arduous to separate shallow blurred boundaries. In this study in SE Iran, gravitational surveying was carried out in shallow areas from the west of Qeshm to the Hormuz islands in a regular network with a distance of one kilometer. The range of gravitational Bouguer was -297 to -330 mGal. Modeling and determining geometrical parameters revealed five negative anomalies from salt penetration. The residual gravity was computed by deducting gravitational effects related to deep sources from measured gravitational data. The hyperbolic tangent function was preferred by comparing the results and employing the tilt angle filter on different gravitational field maps using numerical coding. Correspondingly, estimating the boundary and edge of the subsurface masses will be better than local filters, and anomalies will be highlighted with more intensity. Furthermore, three major fault systems in the Zagros basin were determined as the primary origin of activity and expansion of Hormuz salt. Sensitivity analysis was employed utilizing analytical signals and maps of tilt angle filtering, which both revealed the same satisfying results of -297 to -330 mGal. In this article, the effect of the tilt angle local phase filter on a synthetic model was accomplished through numerical coding. Then the results were analyzed on the gravity data.
Petroleum Science and Technology, 2011
Results in geophysical sciences, Jun 1, 2023
Research Square (Research Square), Feb 7, 2023
Bullet Points • The tilt angle can lessen the sensitivity to existing noises and induction ones. ... more Bullet Points • The tilt angle can lessen the sensitivity to existing noises and induction ones. • Existing lots of noises can make the detection difficult and lead to blurred boundaries. • Geosoft and ModelVision Pro software are employed to map and model Bouguer and residual anomalies to pinpoint anticline oil traps in the surveyed area. • Turtle-back anticlines are typical structures that develop between facing listric growth faults rooted in a flat-lying decollement that help to find salt dome anticlines.
Geophysical investigations are one of the leading efforts in any exploration project that must be... more Geophysical investigations are one of the leading efforts in any exploration project that must be performed ahead of time due to the high excavation expenditures, heavy machinery, and cost reduction. One of the essential geophysical concerns is the estimation of the physical and geometrical parameters of the reserve (geobody), which is done by exploiting the nonlinear inverse modeling of magnetic data. These parameters include depth, volume, shape factor, and type of storage. The present investigation aims to prepare and model magnetic data for proposed drilling sites in the Baba Ali Iron ore deposit in the Hamedan province of Iran. The areal and depth extent of the iron ore geobody was unknown. The Bhattacharyya method by MATLAB software coding was used to minimize the target function and potential field data and create the best fit for the magnetic data. The residual anomaly and model graphs exhibited an excellent two-dimensional conformation in this modeling. Also, 3D modeling co...
Geophysical investigations are one of the leading efforts in any exploration project that must be... more Geophysical investigations are one of the leading efforts in any exploration project that must be performed ahead of time due to the high excavation expenditures, heavy machinery, and cost reduction. One of the essential geophysical concerns is the estimation of the physical and geometrical parameters of the reserve (geobody), which is done by exploiting the nonlinear inverse modeling of magnetic data. These parameters include depth, volume, shape factor, and type of storage. The present investigation aims to prepare and model magnetic data for proposed drilling sites in the Baba Ali Iron ore deposit in the Hamedan province of Iran. The areal and depth extent of the iron ore geobody was unknown. The Bhattacharyya method by MATLAB software coding was used to minimize the target function and potential field data and create the best fit for the magnetic data. The residual anomaly and model graphs exhibited an excellent two-dimensional conformation in this modeling. Also, 3D modeling co...
The analytical signal method and its derivatives can be explicitly calculated and assessed for an... more The analytical signal method and its derivatives can be explicitly calculated and assessed for analyzing and estimating the boundary of geological structures, such as faults or dikes, from potential field anomalies. Gravity field of the east of Qeshm Island and its north coast from Sarkhun to Latidan in SE Iran has been measured in one-kilometer regular network. The regional anomaly effects are deducted from the Bouguer anomaly, where it can get the residual anomalies which is the considered dataset used in this study. The Bouguer range is -297 to -330 milligals (mGal) applying filters and modeling. It was revealed that there are five negative anomalies caused by salt penetration in the region. Regional anomalies expectedly have a low spatial frequency and long wavelengths, while the residual anomalies associated with shallow sub-surface potentials have high spatial frequencies and short-wave wavelengths. Two different fault trends were observed comparing the artificial model using ...
One of the most critical issues in describing gravitational maps is separating the anomalies rela... more One of the most critical issues in describing gravitational maps is separating the anomalies related to shallow sources from the deep ones. In this study, every kilometer of assessing gravity in a very regular network is done from the shallow part of the west of Qeshm Island to Hormoz and its north coast from Sarkhoun to Latidan in SE Iran. The range of gravitational Bouguer changes is from − 297 to-330 miligal (mGal), which after modeling and determining geometrical parameters, It was found that five negative anomalies came from salt penetration in this region. On the Bouguer anomaly maps, profound effects were seen as light and linear, called regional effects. The residual gravity was computed by removing gravitational effects related to deep sources from measured gravitational data. Regional anomalies have a low spatial frequency and long wavelength, while residual anomalies are related to under-surface potentials and have a high spatial frequency and short wavelength. By compari...
Results in Geophysical Sciences
Enhanced Oil Recovery (EOR) process is used to recover additional oil left in place after primary... more Enhanced Oil Recovery (EOR) process is used to recover additional oil left in place after primary recovery. The prediction of its performanceis of great importance in selection and design ofcertain EOR process and future planning for oil production. Microbial Enhance Oil Recovery(MEOR) is friendly with environment, and it isapplied as ex-situ and in-situ in oil reservoirs. In microbial flooding, in the water oil contact themicroorganisms consume the nutrition and producebioacid, biopolymer, biosurfactant, biogas and solvent, which improve the oil recovery and yield theless harmful product for a green environment with respect to other types of EOR methods. This study was investigated potential of applying MEOR by oilrecovery prediction in five different carbonate reservoirs. The study is conducted utilizing 100 laboratory data with valid references. In all of thesereferences, MEOR processes are obtained based on porosity, permeability, salinity, temperature, pressure and PH. Clostrid...
Gas hydrates are easily formed during the transportation of oil and gas when it contains a certai... more Gas hydrates are easily formed during the transportation of oil and gas when it contains a certain amount of water. This paper describes the development and application of Artificial Neural Networks (ANN) that optimized by imperialist competitive algorithm (ICA) for the prediction of natural gas hydrates formation Temperature. In this work after training so ICA-ANN models we find an optimum one that have been used to accurately simulating carbon dioxide hydrate dissociation Temperature. Hence, reliable data of Co 2 were used as input in obtained ICA-ANN model. The obtained results are in the minimum error in compare to experimental.
Drilling industry encounters various challenges during planning and drilling a new well. There ar... more Drilling industry encounters various challenges during planning and drilling a new well. There are numerous parameters related to drilling operations that are planned and adjusted as drillingadvances. Among them, bit selection is one of the most influential considerations for planning and constructing a new borehole. Conventional bit selections are mostly based on drillers’ experiences in the field or mathematical equations, which standmore on recorded performances of similar bits from offset wells. It is evident that these sophisticated interrelations between parameters never can be stated in a single mathematical equation. In such intricate cases, utilizing virtual intelligence and Artificial Neural Networks (ANNs) is proven to be worthwhilein understanding complex relationships between variables. In this paper, two models are developedwith high competence and utilizing ANNs. The first model provides appropriate drilling bit selection based on desired ROP to be obtained by applyin...
International Petroleum Technology Conference, 2013
Drilling industry encounters various challenges during planning and drilling a new well. There ar... more Drilling industry encounters various challenges during planning and drilling a new well. There are numerous parameters related to drilling operations that are planned and adjusted as drilling advances. Among them, bit selection is one of the most influential considerations for planning and constructing a new borehole. Conventional bit selections are mostly based on drillers' experiences in the field or mathematical equations which stand more on recorded performances of similar bits from offset wells. It is evident that these sophisticated interrelations between parameters never can be stated in a single mathematical equation. In such intricate cases, utilizing virtual intelligence and Artificial Neural Networks (ANNs) is proven to be worthwhile in understanding complex relationships between variables. In this paper, two models are developed with high competence and utilizing ANNs. The first model provides appropriate drilling bit selection based on desired ROP to be obtained by applying specific drilling parameters. The second model uses proper drilling parameters obtained from optimizing procedure to select drilling bit which provides maximum achievable ROP. Meanwhile, Genetic Algorithm (GA), as a class of optimizing methods for complex functions, is applied. The proposed methods assess the current conditions of drilling system to optimize the effectiveness of drilling, while reducing the probability of early wear of the drill bit. The correlation coefficients for predicted bit types and optimum drilling parameters in testing the obtained networks are 0.95 and 0.90, respectively. The proposed methodology opens new opportunities for real-time and in-field drilling optimization that can be efficiently implemented within the span of the existing drilling practice.
Petroleum Science and Technology, 2011
The advanced technology has made directional drilling widely applicable in the drilling industry ... more The advanced technology has made directional drilling widely applicable in the drilling industry for different purposes. The trajectory of a directional well is such that it hits the desired target, typically located away from the surface location of the well, at a specified depth and angle. The well trajectory's azimuth and inclination have very obvious and important effects on the directional drilling performance. The aim of this study is to optimize the trajectory of the well to achieve maximum rate of penetration (ROP) as well as maximum possible wellbore stability. To achieve this, a model that predicts the ROP in a directional well is developed using artificial neural networks (ANNs) based on the 15 input parameters. In the modeling, in addition to the azimuth and angle of the well trajectory, drilling operation parameters and principal stresses of the region are included as inputs. The optimizing process is then performed to achieve the maximum rate of penetration to propose the related azimuth and angle of trajectory. Finally, the provided well trajectory is checked to examine the stability of the wellbore. As the final result a well trajectory that provides the maximum rate of penetration as well as the best stability of the wellbore is designed and proposed. This work also considers the properties of different formations existing in the well path, controlling the direction to hit the desired target at the specified depth.
Petroleum Science and Technology, 2011
... to take advantage of ANN modeling to predict the UCS profile by applying drilling parameters ... more ... to take advantage of ANN modeling to predict the UCS profile by applying drilling parameters ... when sufficient sets of inputs and outputs of that function exist is well understood and ... Recent development in application of artificial intelligence in petroleum engineering SPE Paper No ...
Petroleum Science and Technology, 2014
ABSTRACT Wellbore instability, which is considered as failure of borehole wall, is a complex and ... more ABSTRACT Wellbore instability, which is considered as failure of borehole wall, is a complex and time-consuming analysis. Numerous factors such as well path, rock mechanical properties, in situ stress regimes, pore pressure, mud weight, bedding planes, and fractures play a role in borehole instability. Many wellbore stability analyses methods consider only a few of mentioned parameters and majority of them are based on continuum mechanics. However, most of the methods presented for wellbore stability analyses do not consider the impact of fractures. In the present work discrete element models (DEM) are used for numerical wellbore stability analysis of horizontal wells, while the presence of fractures is considered. In this study the effect of mud cyclic loading, hole length, stress regimes, and fluid pressures in fracture plane are examined. The results of analyses showed that direction of minimum horizontal stress is the optimum drilling direction. To evaluate the effects of mud cyclic loadings and open hole lengths, two other models are also considered. These models reveal that mud cyclic loading reduces the stability of borehole. Moreover, it was concluded that mud weight must be increased as open hole length increases and it should not exceed the upper mud weight limit.
Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2012
Tight gas reservoirs are categorized as unconventional gas reservoirs. One of the main characteri... more Tight gas reservoirs are categorized as unconventional gas reservoirs. One of the main characteristics of a tight gas reservoir is the adsorption of gas on the rock surface due to high specific surface area. Desorption is the process of adsorbing gas by the reservoir rock on its surface that is dependent on factors, such as reservoir pressure, reservoir rock type,
Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2013
ABSTRACT Understanding the mechanical properties of formations has its importance in the drilling... more ABSTRACT Understanding the mechanical properties of formations has its importance in the drilling, production, and management phases of reservoirs. In petroleum engineering, measurements through wire-line logs, which run in the boreholes after the drilling phase, are of the most common methods to estimate mechanical properties of different layers. Elastic rock mechanic measurements from logs are dynamic values and need to be upscaled and calibrated to fit the corresponding pseudo-static measurements that are obtained from cores in the laboratory. As a practical approach to having a continuous profile of these static parameters and surmount the arduousness that confronts by using core samples and laboratory tests, many researchers tried to deploy predictive methods and empirical correlations. However, it will be a great advantage to have a real-time estimation of these static parameters while drilling based on bit and formation rock interaction. Artificial neural networks are powerful tools for estimation of complex functions subjected to availability of large enough data sets that present samples of actual behavior of the function. In this study, artificial neural networks were implemented to estimate in situ rock mechanical properties, including Unconfined Compressive Strength, Young's Modulus of Elasticity, and the ratio of these parameters known as Modulus Ratio, by using operational drilling parameters as inputs. Required data were gathered from drilling reports, logging operations, and core samples from nine wells placed in Ahwaz Oilfield located in south-west Iran. The trained networks showed satisfactory low errors in the testing process and sketched the capability of artificial neural networks in estimation of complex functions. The accuracy of the presented model was then compared with the results of calibrated regional correlations and modified Warren's equation. These correlations are used in the candidate wells to estimate Unconfined Compressive Strength and Young's Modulus of Elasticity. It was observed that the new artificial neural network approach is a competent and accurate method for real-time calculation of static elastic properties of formation rocks. The results of this work could be used for drilling optimization, reducing stability problems, and lithologic boundary detection while drilling.
Elsevier, 2023
Noise cancelation is the process done to remove out-of-range anomalies and make better edge bound... more Noise cancelation is the process done to remove out-of-range anomalies and make better edge boundaries interpretation. One of the most challenging issues in describing gravitational maps is separating the anomalies related to shallow sources from the deep ones. Furthermore, Existing noises can make it arduous to separate shallow blurred boundaries. In this study in SE Iran, gravitational surveying was carried out in shallow areas from the west of Qeshm to the Hormuz islands in a regular network with a distance of one kilometer. The range of gravitational Bouguer was -297 to -330 mGal. Modeling and determining geometrical parameters revealed five negative anomalies from salt penetration. The residual gravity was computed by deducting gravitational effects related to deep sources from measured gravitational data. The hyperbolic tangent function was preferred by comparing the results and employing the tilt angle filter on different gravitational field maps using numerical coding. Correspondingly, estimating the boundary and edge of the subsurface masses will be better than local filters, and anomalies will be highlighted with more intensity. Furthermore, three major fault systems in the Zagros basin were determined as the primary origin of activity and expansion of Hormuz salt. Sensitivity analysis was employed utilizing analytical signals and maps of tilt angle filtering, which both revealed the same satisfying results of -297 to -330 mGal. In this article, the effect of the tilt angle local phase filter on a synthetic model was accomplished through numerical coding. Then the results were analyzed on the gravity data.