This study focused on the quantitative analysis of the petrophysical parameters in characterizing the reservoir properties of the Srikail gas field using multi-scale wireline logs.Petrophysical parameters(shale volume...This study focused on the quantitative analysis of the petrophysical parameters in characterizing the reservoir properties of the Srikail gas field using multi-scale wireline logs.Petrophysical parameters(shale volume,porosity,water saturation and hydrocarbon saturation)were estimated from the combination of gamma ray log,resistivity log,density log and neutron log for three hydrocarbon(gas)-bearing zones at well#3.At the first time,log records at 0.1 m and 0.2 m intervals were read for this study.Result showed the average shale volume is 21.07%,53.67%and 51.71%for zone-1,zone-2 and zone-3,respectively.For these zones,the estimated average porosity was 35.89%,29.83%and 28.76%,respectively.The average water saturation of 31.54%,16.83%and 23.39%and average hydrocarbon saturation of 68.46%,83.17%and 76.61%were calculated for zone-1,zone-2 and zone-3,respectively.Thus zone-2 is regarded the most productive zone of well#3.It was found that the values of some parameters(porosity,hydrocarbon saturation and permeability)are higher than the existing results.Therefore,this study confirmed that the log reading at minute/close interval provides better quantitive values of the reservoir’s petrophysical properties.It is expected that this result will contribute to the national gas field development program in future.展开更多
The wireline formation tester （WFT） is an important tool for formation evaluation, such as calculating the formation pressure and permeability, identifying the fluid type, and determining the interface between oil a...The wireline formation tester （WFT） is an important tool for formation evaluation, such as calculating the formation pressure and permeability, identifying the fluid type, and determining the interface between oil and water. However, in a low porosity and low permeability formation, the supercharge pressure effect exists, since the mudcake has a poor sealing ability. The mudcake cannot isolate the hydrostatic pressure of the formation around the borehole and the mud seeps into the formations, leading to inaccurate formation pressure measurement. At the same time, the tool can be easily stuck in the low porosity/low permeability formation due to the long waiting and testing time. We present a method for determining the minimum testing time for the wireline formation tester. The pressure distribution of the mudcake and the formation were respectively calculated with the finite element method （FEM）. The radius of the influence of mud pressure was also computed, and the minimum testing time in low porosity/low permeability formations was determined within a range of values for different formation permeabilities. The determination of the minimum testing time ensures an accurate formation pressure measurement and minimizes possible accidents due to long waiting and testing time.展开更多
This paper presents a 32 Gbps wireline transceiver that not only supports the JESD204 C standard but also maintains back-compatibility with JESD204B with minimal additional circuitry.Additionally,a pattern-filtered ph...This paper presents a 32 Gbps wireline transceiver that not only supports the JESD204 C standard but also maintains back-compatibility with JESD204B with minimal additional circuitry.Additionally,a pattern-filtered phase detector(PFPD)is proposed to circumvent the side effect of ambiguous sampling clock phase caused by loop-unrolled 1st post-cursor tap equalization scheme in the decision-feedback equalization(DFE).A 16 GHz external half-rate clock is injected into an on-chip injection-locked ring oscillator to distribute the 16 GHz clock for both the receiver and the transmitter.Multiple on-chip adaption engines and calibration loops are also added to assist the whole system work properly,such as tap weight and desired level adaption engine integrated into the decision-feedback equalizer,duty cycle distortion correction and IQ-mismatch correction.Fabricated in 28 nm CMOS process,the proposed transceiver demonstrates its ability to operate within a signaling range from 312.5 Mbps to 32 Gbps,achieving a BER below 10−12 over a 14.9 dB channel loss at Nyquist frequency.It occupies an aggregated area of 1.4 mm^(2)and consumes 203 mW at 32 Gbps,in which 50 mW for the transmitter(TX)and 153 mW for the receiver(RX),therefore end up achieving 6.34pJ/bit power efficiency at 32 Gbps.展开更多
The travel time of rock compressional waves is an essential parameter used for estimating important rock properties,such as porosity,permeability,and lithology.Current methods,like wireline logging tests,provide broad...The travel time of rock compressional waves is an essential parameter used for estimating important rock properties,such as porosity,permeability,and lithology.Current methods,like wireline logging tests,provide broad measurements but lack finer resolution.Laboratory-based rock core measurements offer higher resolution but are resource-intensive.Conventionally,wireline logging and rock core measurements have been used independently.This study introduces a novel approach that integrates both data sources.The method leverages the detailed features from limited core data to enhance the resolution of wireline logging data.By combining machine learning with random field theory,the method allows for probabilistic predictions in regions with sparse data sampling.In this framework,12 parameters from wireline tests are used to predict trends in rock core data.The residuals are modeled using random field theory.The outcomes are high-resolution predictions that combine both the predicted trend and the probabilistic realizations of the residual.By utilizing unconditional and conditional random field theories,this method enables unconditional and conditional simulations of the underlying high-resolution rock compressional wave travel time profile and provides uncertainty estimates.This integrated approach optimizes the use of existing core and logging data.Its applicability is confirmed in an oil project in West China.展开更多
In this study, an integrated approach for diagenetic facies classification, reservoir quality analysis and quantitative wireline log prediction of tight gas sandstones(TGSs) is introduced utilizing a combination of fi...In this study, an integrated approach for diagenetic facies classification, reservoir quality analysis and quantitative wireline log prediction of tight gas sandstones(TGSs) is introduced utilizing a combination of fit-for-purpose complementary testing and machine learning techniques. The integrated approach is specialized for the middle Permian Shihezi Formation TGSs in the northeastern Ordos Basin, where operators often face significant drilling uncertainty and increased exploration risks due to low porosities and micro-Darcy range permeabilities. In this study, detrital compositions and diagenetic minerals and their pore type assemblages were analyzed using optical light microscopy, cathodoluminescence, standard scanning electron microscopy, and X-ray diffraction. Different types of diagenetic facies were delineated on this basis to capture the characteristic rock properties of the TGSs in the target formation.A combination of He porosity and permeability measurements, mercury intrusion capillary pressure and nuclear magnetic resonance data was used to analyze the mechanism of heterogeneous TGS reservoirs.We found that the type, size and proportion of pores considerably varied between diagenetic facies due to differences in the initial depositional attributes and subsequent diagenetic alterations;these differences affected the size, distribution and connectivity of the pore network and varied the reservoir quality. Five types of diagenetic facies were classified:(i) grain-coating facies, which have minimal ductile grains, chlorite coatings that inhibit quartz overgrowths, large intergranular pores that dominate the pore network, the best pore structure and the greatest reservoir quality;(ii) quartz-cemented facies,which exhibit strong quartz overgrowths, intergranular porosity and a pore size decrease, resulting in the deterioration of the pore structure and reservoir quality;(iii) mixed-cemented facies, in which the cementation of various authigenic minerals increases the micropores, resulting in a poor pore structure and reservoir quality;(iv) carbonate-cemented facies and(v) tightly compacted facies, in which the intergranular pores are filled with carbonate cement and ductile grains;thus, the pore network mainly consists of micropores with small pore throat sizes, and the pore structure and reservoir quality are the worst. The grain-coating facies with the best reservoir properties are more likely to have high gas productivity and are the primary targets for exploration and development. The diagenetic facies were then translated into wireline log expressions(conventional and NMR logging). Finally, a wireline log quantitative prediction model of TGSs using convolutional neural network machine learning algorithms was established to successfully classify the different diagenetic facies.展开更多
Wellbore instability and sand production are all common challenges in the Niger Delta oil province,resulting in high drilling and production cost as well as damage to oil facilities.The vulnerability of lithologic for...Wellbore instability and sand production are all common challenges in the Niger Delta oil province,resulting in high drilling and production cost as well as damage to oil facilities.The vulnerability of lithologic formations to wellbore instability and resultant sand production is investigated in the four delineated reservoirs of the“Areo”field,western part of Niger Delta Basin.The foundation for establishing the geomechanical properties in this study was a 1-dimensional mechanical earth model,using gamma ray(GR),density(RHOB),compressional slowness(DTC),and shear slowness(DTS)logs.Within the Areo oil field,two wells(well 001 and well 002)were correlated.The evaluated formations are still primarily composed of compacted shale and unconsolidated sandstone,with reservoir sand units exhibiting lower elastic and rock strength properties than shale units.High compressibility and porosity make sand more brittle,while low compressibility and porosity make shale stiffer due to high moduli.The maximum force that can be applied to a shale unit without causing it to fail is 17.23 MPa,which is the maximum average rock strength of the shale.It means that shale requires more vertical stress or pressure than sand does in order to deform it(15.06 MPa).The three sand prediction approaches used in the analysis of sand production predictions have cut-off values that are higher than the average values of the formations.The Schlumberger sand production index method(S/I)indicates that the reservoir has potential for sand influx in the two wells,with the average of the four reservoirs studied in wells 001 and 002 being 1.551012 psi and 1.141012 psi respectively.However,when a formation's sand production index is less than 1.241012 psi,as it is in this study,the formation is likely to produce sand.These findings support the notion that the defined sandstone units are highly unconsolidated and have a high potential for producing sands;therefore,sand control techniques must be factored into process optimization and cost reduction plans.展开更多
In this paper, we propose a hybrid PML （H-PML） combining the normal absorption factor of convolutional PML （C-PML） with tangential absorption factor of Mutiaxial PML （M-PML）. The H-PML boundary conditions can be...In this paper, we propose a hybrid PML （H-PML） combining the normal absorption factor of convolutional PML （C-PML） with tangential absorption factor of Mutiaxial PML （M-PML）. The H-PML boundary conditions can better suppress the numerical instability in some extreme models, and the computational speed of finite-element method and the dynamic range are greatly increased using this HPML. We use the finite-element method with a hybrid PML to model the acoustic reflection of the interface when wireline and well logging while drilling （LWD）, in a formation with a reflector outside the borehole. The simulation results suggests that the PS- and SP- reflected waves arrive at the same time when the inclination between the well and the outer interface is zero, and the difference in arrival times increases with increasing dip angle. When there are fractures outside the well, the reflection signal is clearer in the subsequent reflection waves and may be used to identify the fractured zone. The difference between the dominant wavelength and the model scale shows that LWD reflection logging data are of higher resolution and quality than wireline acoustic reflection logging.展开更多
Gas Ratio Analysis is best of the analysis in mud logging system which during drilling time is very important for catch formation. This analysis can help geologist that to decide which layers have oil and gas. Also wi...Gas Ratio Analysis is best of the analysis in mud logging system which during drilling time is very important for catch formation. This analysis can help geologist that to decide which layers have oil and gas. Also with this analysis, we can compare that wireline jobs has been right place or not. So after calculate ratio analyses, we can put same place then can compare with wireline curves. In that time, we can see that where exactly have oil and gas. With this method, we can reduce cost and we can do safety job. In Azerbaijan Gas Ratio Analysis has been used in Pirsa at Oil field and has been gotten good result after perforation. Now this method use in Hovsan and Zigh oil field by the mudloggers which belong Surachani district.展开更多
Smart Grid (SG) is an emerging paradigm of the modern world to upgrade and enhance the existing conventional electrical power infrastructure from generation to distribution to the consumers in a two-way communication ...Smart Grid (SG) is an emerging paradigm of the modern world to upgrade and enhance the existing conventional electrical power infrastructure from generation to distribution to the consumers in a two-way communication fashion to automate the electrical power demand and supply and make this a cyber-physical system. SG infrastructure key elements, such as smart meters, circuit breakers, transformers, feeders, substations, control centers, grid stations, are required well-formed communication network architectures. SG infrastructure is divided into three main communication networks architectures, such as HAH, NAN, and WAN. Each of these communication network architectures requires reliable, stable, secure, high data rate at real-time with the help of different wireline and wireless communication technologies from HAN to WAN networks. To understand the complete concepts about SG, a concise review is presented and it will help the readers to get foundations of communication network architectures and technologies of SG.展开更多
The objective is to empower the reader and scientific community with the knowledge and specific applicable equations to then reproduce the critical rock and fluid attributes in the Powder River Basin. To then continue...The objective is to empower the reader and scientific community with the knowledge and specific applicable equations to then reproduce the critical rock and fluid attributes in the Powder River Basin. To then continue to unravel the basin and its potential (both conventionally and unconventionally). The overall goal is to ensure the transfer of knowledge and </span><span style="font-family:Verdana;">communication of a petrophysical workflow that can then also influence application to </span><span style="font-family:Verdana;">other basins worldwide. </span><span style="font-family:Verdana;">The Powder River Basin is in southeast Montana and northeast Wyoming and is a prolific oil and gas (hydrocarbon-prone) sedimentary basin related to the greater </span><span style="font-family:Verdana;">Rockies chain/series of hydrocarbon-bearing basins (ex. Big Horn, Greater Green River, </span><span style="font-family:Verdana;">Denver-Jules). In this study, we briefly set-up the geological background of the Powder River Basin and the importance/ relevance to then tackling subsurface petrophysical evaluation on a regional scale. Approximately, 200 wells were evaluated petrophysically by a combined deterministic and inversion-based workflow representing an effort to share best practices, ap</span><span style="font-family:Verdana;">proaches, and the relative trends to apply in the basin to unravel the stratigraphic hydrocarbon potential in place. An extensive workflow involving basic petrophysical approaches such as raw log applicable cutoffs and volume of clay determination are shared as well as extending </span><span style="font-family:Verdana;">knowledge and application into advanced petrophysics through geochemical property derivation and impact of those derived properties as well as bound versus free water and hydrocar</span><span style="font-family:Verdana;">bon understanding. Results of the petrophysical analysis highlight the varying properties in conventional and unconventional formations (example Niobrara). The results of how and why the petrophysical approach was calibrated and then applied are the primary efforts ac</span><span style="font-family:Verdana;">complished.展开更多
In normal pressure of reservoir, formation pressure and depth can not fully reflect the linear relationship between the formation pressure with depth, the change rule of reservoir measured formation pressure and often...In normal pressure of reservoir, formation pressure and depth can not fully reflect the linear relationship between the formation pressure with depth, the change rule of reservoir measured formation pressure and often reduced pressure, understanding unclear cause fluid properties. By introducing basic principles of hydrostatics. The relationship between pressure coefficient and mathematical depth is discussed by mathematical induction analysis of measured pressure data of nearly 50 normal pressure reservoirs in Bohai Oilfield. The results show that the reservoir pressure data is linearly distributed with depth, and the pressure coefficient is inversely proportional to depth. When the depth becomes shallower, the pressure coefficient increases and approaches the reservoir level. As the depth increases, the pressure coefficient decreases and approaches the hydrostatic pressure coefficient infinitely. The study can more accurately analyze the reservoir pressure changes, which is helpful to study the oil and water distribution, reservoir connectivity and fluid properties of atmospheric pressure reservoirs.展开更多
This paper provides a comprehensive overview of Deep Transient Testing(DTT),a cutting-edge technique for reservoir characterization that has revolutionized the oil and gas industry.The main aim of DTT is to characteri...This paper provides a comprehensive overview of Deep Transient Testing(DTT),a cutting-edge technique for reservoir characterization that has revolutionized the oil and gas industry.The main aim of DTT is to characterize the reservoir with a deeper radius of investigation.The optimization of the radius of investigation with the DTT approach is studied in detail.Reveal is a commercial numerical simulation application used to simulate the DTT process and evaluate the pressure wave analysis in the porous media.The main aim of the simulation is to understand the impact of the reservoir quality on the pressure response and use it to address the noise-to-pule ratio,which is a determinantal parameter in testing duration.The tested wells with the DTT tool show that measured well productivity can deliver the minimum commercial rate.The has been delivered within 2 days compared to the potential test time of 21 days which saved the 19 rig days and contributed to C02 emission reduction of(gas flaring 1340+rig emission 600)1940 Metric tons equivalent to 421 cars emission in a year.However,DTT also presents certain limitations,such as the requirement for specialized equipment and expertise,as well as the potential for formation damage during testing.This study provides a detailed description of the DTT technique,encompassing its history,theory,and practical applications.Furthermore,it discusses the benefits and limitations of DTT and presents case studies to illustrate its effectiveness across various reservoir types.Overall,this study serves as a valuable resource for reservoir engineers,geologists,and other professionals involved in the exploration and production of oil and gas.展开更多
Porosity is one of the main parameters that should be considered when a gas or an oil field is assessed.Hence,the availability of porosity is crucial in any rock and formation analysis.However,this parameter is not al...Porosity is one of the main parameters that should be considered when a gas or an oil field is assessed.Hence,the availability of porosity is crucial in any rock and formation analysis.However,this parameter is not always available and direct measurement is scarce and usually is confined to appraisal phase of a field.Therefore,in this study it is aimed to find a relationship in order to estimate porosity in afterward phases.The data of 5 appraisal wells of an undeveloped gas field has been gathered to perform this purpose.The full set wireline logging data and drilling data were available.The data inherit high level of fluctuation which is normal with respect to real direct measured data.The smoothed curving was utilized and as a result,the fluctuation was diminished considerably and the feasibility of carrying out the investigation was being established,accordingly.To normalize and gather drilling data in a parameter in order to have a better view and investigation,sigmalog method was employed.It was observed that there is a clear exponential relationship between porosity and drilling data and curve fitting was utilized to conduct a numerical relationship.The curve fitting was established with R^(2)=0.83 and a trustworthy fitting resulted.The results demonstrate the possibility of porosity estimation by using drilling data.Furthermore,a numerical relationship is given for a specific field.The porosity estimation can lead to better analysis of newly drilled rocks and formations leading to more efficient field development strategies.展开更多
基金the K.C. Wong Education Foundation (GJTD-2019-04)the Chinese Academy of Sciences as President ’s International Fellowship Initiative (PIFI) for a Postdoctoral fellow to M. Moklesur Rahman (2019PE0025).
文摘This study focused on the quantitative analysis of the petrophysical parameters in characterizing the reservoir properties of the Srikail gas field using multi-scale wireline logs.Petrophysical parameters(shale volume,porosity,water saturation and hydrocarbon saturation)were estimated from the combination of gamma ray log,resistivity log,density log and neutron log for three hydrocarbon(gas)-bearing zones at well#3.At the first time,log records at 0.1 m and 0.2 m intervals were read for this study.Result showed the average shale volume is 21.07%,53.67%and 51.71%for zone-1,zone-2 and zone-3,respectively.For these zones,the estimated average porosity was 35.89%,29.83%and 28.76%,respectively.The average water saturation of 31.54%,16.83%and 23.39%and average hydrocarbon saturation of 68.46%,83.17%and 76.61%were calculated for zone-1,zone-2 and zone-3,respectively.Thus zone-2 is regarded the most productive zone of well#3.It was found that the values of some parameters(porosity,hydrocarbon saturation and permeability)are higher than the existing results.Therefore,this study confirmed that the log reading at minute/close interval provides better quantitive values of the reservoir’s petrophysical properties.It is expected that this result will contribute to the national gas field development program in future.
文摘The wireline formation tester （WFT） is an important tool for formation evaluation, such as calculating the formation pressure and permeability, identifying the fluid type, and determining the interface between oil and water. However, in a low porosity and low permeability formation, the supercharge pressure effect exists, since the mudcake has a poor sealing ability. The mudcake cannot isolate the hydrostatic pressure of the formation around the borehole and the mud seeps into the formations, leading to inaccurate formation pressure measurement. At the same time, the tool can be easily stuck in the low porosity/low permeability formation due to the long waiting and testing time. We present a method for determining the minimum testing time for the wireline formation tester. The pressure distribution of the mudcake and the formation were respectively calculated with the finite element method （FEM）. The radius of the influence of mud pressure was also computed, and the minimum testing time in low porosity/low permeability formations was determined within a range of values for different formation permeabilities. The determination of the minimum testing time ensures an accurate formation pressure measurement and minimizes possible accidents due to long waiting and testing time.
基金supported by Beijing Municipal Science and Technology through Project Number Z221100007722024.
文摘This paper presents a 32 Gbps wireline transceiver that not only supports the JESD204 C standard but also maintains back-compatibility with JESD204B with minimal additional circuitry.Additionally,a pattern-filtered phase detector(PFPD)is proposed to circumvent the side effect of ambiguous sampling clock phase caused by loop-unrolled 1st post-cursor tap equalization scheme in the decision-feedback equalization(DFE).A 16 GHz external half-rate clock is injected into an on-chip injection-locked ring oscillator to distribute the 16 GHz clock for both the receiver and the transmitter.Multiple on-chip adaption engines and calibration loops are also added to assist the whole system work properly,such as tap weight and desired level adaption engine integrated into the decision-feedback equalizer,duty cycle distortion correction and IQ-mismatch correction.Fabricated in 28 nm CMOS process,the proposed transceiver demonstrates its ability to operate within a signaling range from 312.5 Mbps to 32 Gbps,achieving a BER below 10−12 over a 14.9 dB channel loss at Nyquist frequency.It occupies an aggregated area of 1.4 mm^(2)and consumes 203 mW at 32 Gbps,in which 50 mW for the transmitter(TX)and 153 mW for the receiver(RX),therefore end up achieving 6.34pJ/bit power efficiency at 32 Gbps.
基金the Australian Government through the Australian Research Council's Discovery Projects funding scheme(Project DP190101592)the National Natural Science Foundation of China(Grant Nos.41972280 and 52179103).
文摘The travel time of rock compressional waves is an essential parameter used for estimating important rock properties,such as porosity,permeability,and lithology.Current methods,like wireline logging tests,provide broad measurements but lack finer resolution.Laboratory-based rock core measurements offer higher resolution but are resource-intensive.Conventionally,wireline logging and rock core measurements have been used independently.This study introduces a novel approach that integrates both data sources.The method leverages the detailed features from limited core data to enhance the resolution of wireline logging data.By combining machine learning with random field theory,the method allows for probabilistic predictions in regions with sparse data sampling.In this framework,12 parameters from wireline tests are used to predict trends in rock core data.The residuals are modeled using random field theory.The outcomes are high-resolution predictions that combine both the predicted trend and the probabilistic realizations of the residual.By utilizing unconditional and conditional random field theories,this method enables unconditional and conditional simulations of the underlying high-resolution rock compressional wave travel time profile and provides uncertainty estimates.This integrated approach optimizes the use of existing core and logging data.Its applicability is confirmed in an oil project in West China.
基金financially supported by the National Natural Science Foundation of China (No. 42272156)research on efficient exploration and development technology for tight stone gas of China United Coalbed Methane Corporation (No. ZZGSECCYWG 2021-322)。
文摘In this study, an integrated approach for diagenetic facies classification, reservoir quality analysis and quantitative wireline log prediction of tight gas sandstones(TGSs) is introduced utilizing a combination of fit-for-purpose complementary testing and machine learning techniques. The integrated approach is specialized for the middle Permian Shihezi Formation TGSs in the northeastern Ordos Basin, where operators often face significant drilling uncertainty and increased exploration risks due to low porosities and micro-Darcy range permeabilities. In this study, detrital compositions and diagenetic minerals and their pore type assemblages were analyzed using optical light microscopy, cathodoluminescence, standard scanning electron microscopy, and X-ray diffraction. Different types of diagenetic facies were delineated on this basis to capture the characteristic rock properties of the TGSs in the target formation.A combination of He porosity and permeability measurements, mercury intrusion capillary pressure and nuclear magnetic resonance data was used to analyze the mechanism of heterogeneous TGS reservoirs.We found that the type, size and proportion of pores considerably varied between diagenetic facies due to differences in the initial depositional attributes and subsequent diagenetic alterations;these differences affected the size, distribution and connectivity of the pore network and varied the reservoir quality. Five types of diagenetic facies were classified:(i) grain-coating facies, which have minimal ductile grains, chlorite coatings that inhibit quartz overgrowths, large intergranular pores that dominate the pore network, the best pore structure and the greatest reservoir quality;(ii) quartz-cemented facies,which exhibit strong quartz overgrowths, intergranular porosity and a pore size decrease, resulting in the deterioration of the pore structure and reservoir quality;(iii) mixed-cemented facies, in which the cementation of various authigenic minerals increases the micropores, resulting in a poor pore structure and reservoir quality;(iv) carbonate-cemented facies and(v) tightly compacted facies, in which the intergranular pores are filled with carbonate cement and ductile grains;thus, the pore network mainly consists of micropores with small pore throat sizes, and the pore structure and reservoir quality are the worst. The grain-coating facies with the best reservoir properties are more likely to have high gas productivity and are the primary targets for exploration and development. The diagenetic facies were then translated into wireline log expressions(conventional and NMR logging). Finally, a wireline log quantitative prediction model of TGSs using convolutional neural network machine learning algorithms was established to successfully classify the different diagenetic facies.
文摘Wellbore instability and sand production are all common challenges in the Niger Delta oil province,resulting in high drilling and production cost as well as damage to oil facilities.The vulnerability of lithologic formations to wellbore instability and resultant sand production is investigated in the four delineated reservoirs of the“Areo”field,western part of Niger Delta Basin.The foundation for establishing the geomechanical properties in this study was a 1-dimensional mechanical earth model,using gamma ray(GR),density(RHOB),compressional slowness(DTC),and shear slowness(DTS)logs.Within the Areo oil field,two wells(well 001 and well 002)were correlated.The evaluated formations are still primarily composed of compacted shale and unconsolidated sandstone,with reservoir sand units exhibiting lower elastic and rock strength properties than shale units.High compressibility and porosity make sand more brittle,while low compressibility and porosity make shale stiffer due to high moduli.The maximum force that can be applied to a shale unit without causing it to fail is 17.23 MPa,which is the maximum average rock strength of the shale.It means that shale requires more vertical stress or pressure than sand does in order to deform it(15.06 MPa).The three sand prediction approaches used in the analysis of sand production predictions have cut-off values that are higher than the average values of the formations.The Schlumberger sand production index method(S/I)indicates that the reservoir has potential for sand influx in the two wells,with the average of the four reservoirs studied in wells 001 and 002 being 1.551012 psi and 1.141012 psi respectively.However,when a formation's sand production index is less than 1.241012 psi,as it is in this study,the formation is likely to produce sand.These findings support the notion that the defined sandstone units are highly unconsolidated and have a high potential for producing sands;therefore,sand control techniques must be factored into process optimization and cost reduction plans.
基金supported by the National Natural Science Foundation of China(No.41204094)Science Foundation of China University of Petroleum,Beijing(No.2462015YQ0506)
文摘In this paper, we propose a hybrid PML （H-PML） combining the normal absorption factor of convolutional PML （C-PML） with tangential absorption factor of Mutiaxial PML （M-PML）. The H-PML boundary conditions can better suppress the numerical instability in some extreme models, and the computational speed of finite-element method and the dynamic range are greatly increased using this HPML. We use the finite-element method with a hybrid PML to model the acoustic reflection of the interface when wireline and well logging while drilling （LWD）, in a formation with a reflector outside the borehole. The simulation results suggests that the PS- and SP- reflected waves arrive at the same time when the inclination between the well and the outer interface is zero, and the difference in arrival times increases with increasing dip angle. When there are fractures outside the well, the reflection signal is clearer in the subsequent reflection waves and may be used to identify the fractured zone. The difference between the dominant wavelength and the model scale shows that LWD reflection logging data are of higher resolution and quality than wireline acoustic reflection logging.
文摘Gas Ratio Analysis is best of the analysis in mud logging system which during drilling time is very important for catch formation. This analysis can help geologist that to decide which layers have oil and gas. Also with this analysis, we can compare that wireline jobs has been right place or not. So after calculate ratio analyses, we can put same place then can compare with wireline curves. In that time, we can see that where exactly have oil and gas. With this method, we can reduce cost and we can do safety job. In Azerbaijan Gas Ratio Analysis has been used in Pirsa at Oil field and has been gotten good result after perforation. Now this method use in Hovsan and Zigh oil field by the mudloggers which belong Surachani district.
文摘Smart Grid (SG) is an emerging paradigm of the modern world to upgrade and enhance the existing conventional electrical power infrastructure from generation to distribution to the consumers in a two-way communication fashion to automate the electrical power demand and supply and make this a cyber-physical system. SG infrastructure key elements, such as smart meters, circuit breakers, transformers, feeders, substations, control centers, grid stations, are required well-formed communication network architectures. SG infrastructure is divided into three main communication networks architectures, such as HAH, NAN, and WAN. Each of these communication network architectures requires reliable, stable, secure, high data rate at real-time with the help of different wireline and wireless communication technologies from HAN to WAN networks. To understand the complete concepts about SG, a concise review is presented and it will help the readers to get foundations of communication network architectures and technologies of SG.
文摘The objective is to empower the reader and scientific community with the knowledge and specific applicable equations to then reproduce the critical rock and fluid attributes in the Powder River Basin. To then continue to unravel the basin and its potential (both conventionally and unconventionally). The overall goal is to ensure the transfer of knowledge and </span><span style="font-family:Verdana;">communication of a petrophysical workflow that can then also influence application to </span><span style="font-family:Verdana;">other basins worldwide. </span><span style="font-family:Verdana;">The Powder River Basin is in southeast Montana and northeast Wyoming and is a prolific oil and gas (hydrocarbon-prone) sedimentary basin related to the greater </span><span style="font-family:Verdana;">Rockies chain/series of hydrocarbon-bearing basins (ex. Big Horn, Greater Green River, </span><span style="font-family:Verdana;">Denver-Jules). In this study, we briefly set-up the geological background of the Powder River Basin and the importance/ relevance to then tackling subsurface petrophysical evaluation on a regional scale. Approximately, 200 wells were evaluated petrophysically by a combined deterministic and inversion-based workflow representing an effort to share best practices, ap</span><span style="font-family:Verdana;">proaches, and the relative trends to apply in the basin to unravel the stratigraphic hydrocarbon potential in place. An extensive workflow involving basic petrophysical approaches such as raw log applicable cutoffs and volume of clay determination are shared as well as extending </span><span style="font-family:Verdana;">knowledge and application into advanced petrophysics through geochemical property derivation and impact of those derived properties as well as bound versus free water and hydrocar</span><span style="font-family:Verdana;">bon understanding. Results of the petrophysical analysis highlight the varying properties in conventional and unconventional formations (example Niobrara). The results of how and why the petrophysical approach was calibrated and then applied are the primary efforts ac</span><span style="font-family:Verdana;">complished.
文摘In normal pressure of reservoir, formation pressure and depth can not fully reflect the linear relationship between the formation pressure with depth, the change rule of reservoir measured formation pressure and often reduced pressure, understanding unclear cause fluid properties. By introducing basic principles of hydrostatics. The relationship between pressure coefficient and mathematical depth is discussed by mathematical induction analysis of measured pressure data of nearly 50 normal pressure reservoirs in Bohai Oilfield. The results show that the reservoir pressure data is linearly distributed with depth, and the pressure coefficient is inversely proportional to depth. When the depth becomes shallower, the pressure coefficient increases and approaches the reservoir level. As the depth increases, the pressure coefficient decreases and approaches the hydrostatic pressure coefficient infinitely. The study can more accurately analyze the reservoir pressure changes, which is helpful to study the oil and water distribution, reservoir connectivity and fluid properties of atmospheric pressure reservoirs.
文摘This paper provides a comprehensive overview of Deep Transient Testing(DTT),a cutting-edge technique for reservoir characterization that has revolutionized the oil and gas industry.The main aim of DTT is to characterize the reservoir with a deeper radius of investigation.The optimization of the radius of investigation with the DTT approach is studied in detail.Reveal is a commercial numerical simulation application used to simulate the DTT process and evaluate the pressure wave analysis in the porous media.The main aim of the simulation is to understand the impact of the reservoir quality on the pressure response and use it to address the noise-to-pule ratio,which is a determinantal parameter in testing duration.The tested wells with the DTT tool show that measured well productivity can deliver the minimum commercial rate.The has been delivered within 2 days compared to the potential test time of 21 days which saved the 19 rig days and contributed to C02 emission reduction of(gas flaring 1340+rig emission 600)1940 Metric tons equivalent to 421 cars emission in a year.However,DTT also presents certain limitations,such as the requirement for specialized equipment and expertise,as well as the potential for formation damage during testing.This study provides a detailed description of the DTT technique,encompassing its history,theory,and practical applications.Furthermore,it discusses the benefits and limitations of DTT and presents case studies to illustrate its effectiveness across various reservoir types.Overall,this study serves as a valuable resource for reservoir engineers,geologists,and other professionals involved in the exploration and production of oil and gas.
文摘Porosity is one of the main parameters that should be considered when a gas or an oil field is assessed.Hence,the availability of porosity is crucial in any rock and formation analysis.However,this parameter is not always available and direct measurement is scarce and usually is confined to appraisal phase of a field.Therefore,in this study it is aimed to find a relationship in order to estimate porosity in afterward phases.The data of 5 appraisal wells of an undeveloped gas field has been gathered to perform this purpose.The full set wireline logging data and drilling data were available.The data inherit high level of fluctuation which is normal with respect to real direct measured data.The smoothed curving was utilized and as a result,the fluctuation was diminished considerably and the feasibility of carrying out the investigation was being established,accordingly.To normalize and gather drilling data in a parameter in order to have a better view and investigation,sigmalog method was employed.It was observed that there is a clear exponential relationship between porosity and drilling data and curve fitting was utilized to conduct a numerical relationship.The curve fitting was established with R^(2)=0.83 and a trustworthy fitting resulted.The results demonstrate the possibility of porosity estimation by using drilling data.Furthermore,a numerical relationship is given for a specific field.The porosity estimation can lead to better analysis of newly drilled rocks and formations leading to more efficient field development strategies.
