We esta blished our primary theory and method for processing and interpretating the thin in-terbed as an objective exploration.Based on the in-troduction of the maximum likelyhood function of probability statistics,st...We esta blished our primary theory and method for processing and interpretating the thin in-terbed as an objective exploration.Based on the in-troduction of the maximum likelyhood function of probability statistics,state variable model and re-currence estimation and examination theory,the“SO>ftv ware maximum likelyhood deconvolution’and“DELOP”has been developed.By using it,reflec-tivity with high resolution and high signal/noise ra-tio,minimum phase v wav elets,1 re.lative.interval ve-locities,absolute interval velocities and synthetic.展开更多
Introduction
Owing to long-time running, more facilities including stations, pipelines, vessels have become corrosive and aged ,some process has grown old, it has exert more burden for the maintenance and repair.Simul...Introduction
Owing to long-time running, more facilities including stations, pipelines, vessels have become corrosive and aged ,some process has grown old, it has exert more burden for the maintenance and repair.Simultaneously, the fluid production rate, oil production rate and water injection rate has changed greatly so that the inflicts and problems from the established surface systems will become more obvious. Energy cost of production and running has increasing continuously. Capacity has been unbalance in systems and areas.展开更多
Many EOR methods have been tested after water flooding in Daqing Oilfield.CO\-2,natural gas, micellar, microbial, steam, polymer and ASP flooding have been tested in the lab and field (some field tests have been perfo...Many EOR methods have been tested after water flooding in Daqing Oilfield.CO\-2,natural gas, micellar, microbial, steam, polymer and ASP flooding have been tested in the lab and field (some field tests have been performed). Most of the results are good. CO\-2,natural gas,micellar are not suitable to be used in Daqing Oilfield. Polymer flooding of pilots and industrial scale have been successful. The results of polymer flooding are related closely to the injection parameters and injection methods. The incremental oil production are 100 to 140 tons of oil per ton of polymer injected. The oil recovery increased 10% to 14%OOIP. ASP flooding is successful. The cost of chemicals per barrel of incremental oil is $4 0 to $6 2.The incremental recovery is 18% to 20% OOIP over water flooding.展开更多
Geodetic deformation severely affects the development of the oilfield and probably causes casing damage or abandonment of injection wells and producers. Therefore, it is meaningful to survey and study three-dimensiona...Geodetic deformation severely affects the development of the oilfield and probably causes casing damage or abandonment of injection wells and producers. Therefore, it is meaningful to survey and study three-dimensional geodetic deformation in the process of the oilfield development. In order to study this issue, 11-year long term surveying of three-dimensional geodetic deformation has been carried out while developing Naner area in Daqing oilfield. Basic rules of 3-D geodetic deformation have been obtained through surveying. Results show that production and injection under high pressure may cause the changes of surface elevation, and geodetic deformation correlates with simultaneous formation pressure. Precautions and relative technological measurements have been put forward in the waterflood development in Naner region and provide theoretical guidelines for the production and casing preservation of the oilfield. Finally, surveying results are interpreted by porous elastic theory. Mathematical model to calculate 3-D geodetic deformation is put forward in the course of the oilfield development.展开更多
Daqing Oilfield is located in the northeast of Songnen Plain in Daqing City, Heilongjiang Province, which is a petrochemical industry gathering place based on petroleum refining, chemical industry, chemical fiber and ...Daqing Oilfield is located in the northeast of Songnen Plain in Daqing City, Heilongjiang Province, which is a petrochemical industry gathering place based on petroleum refining, chemical industry, chemical fiber and fertilizer. In recent years, the quantity demand of petroleum and petrochemical production for groundwater in Daqing Oilfield is growing, and it's of great significance to analyze and study the quality and pollution degree of groundwater for groundwater exploitation, utilization and protection. In this paper, groundwater quality of Daqing Oilfield evaluated by Nemerow Index is poor, and most points are Class IV groundwater; When evaluating groundwater pollution by hierarchical ladder method, the results show that the severe and extremely severe pollution points account for 34.48% in shallow phreatic water and 20% in deep confined water, showing that shallow groundwater is more seriously polluted than the deep. The main components influencing the quality of groundwater in the study area are total hardness, total dissolved solids, Cl^-, SO_4^(2-) and so on, which are affected by both the native environment and human activities; The main pollution components in groundwater are nitrite and nitrate nitrogen which are affected by human activities. Daqing Oilfield groundwater pollution is characterized by inorganic pollution, while organic components related to human activities contribute less to the groundwater pollution currently.展开更多
By tracking and analyzing the research and practices of chemical flooding carried out in the Daqing Oilfield, NE China since the 1970 s, the chemical flooding theory, technology adaptability and existing problems were...By tracking and analyzing the research and practices of chemical flooding carried out in the Daqing Oilfield, NE China since the 1970 s, the chemical flooding theory, technology adaptability and existing problems were systematically summarized, and directions and ideas of development in the future were proposed. In enhanced oil recovery by chemical flooding, the Daqing Oilfield developed theories related to compatibility between crude oil and surfactant that may form ultra-low interfacial tensions with low-acidity oil, and a series of surfactant products were developed independently. The key technologies for chemical flooding such as injection parameter optimization and numerical simulation were established. The technologies of separation injection, cleansing and anti-scaling, preparation and injection, and produced liquid processing were developed. The matching technologies of production engineering and surface facilities were formed. Through implementation of chemical flooding, the Daqing Oilfield achieved outstanding performances with enhanced recovery rate of 12% in polymer flooding and with enhanced recovery rate of 18% in ASP flooding. To further enhance the oil recovery of chemical flooding, three aspects need to be studied:(1) fine characterization of reservoirs;(2) smart and efficient recovery enhancement technologies;(3) environment friendly, high-efficiency and smart matching processes.展开更多
Exploration for oil and deep gas in northern Songliao Basin,complex rift basin—Hailaer Basin,and Yi-Shu Graben in peripheral basin has technical challenge.Researches on supporting technology including seismic acquisi...Exploration for oil and deep gas in northern Songliao Basin,complex rift basin—Hailaer Basin,and Yi-Shu Graben in peripheral basin has technical challenge.Researches on supporting technology including seismic acquisition,processing and interpretation,logging and drilling are performed to establish high resolution 3D seismic technology for lithologic reservoir,deep volcanic rock and complex rift basin,reservoir evaluation and stimulation technology for low permeability reservoir,volcanic reservoir and complex rift reservoir,and drilling technology for deep volcanic rock,providing technical support for reserves increase in northern Songliao Basin,large gas reservoirs discovery in deep volcanic rock and exploration progress in complex rift basin.Next-step development trend of exploration technology is proposed to meet the demand of more technical challenges in the future.展开更多
The Class-Ⅲ oil reservoirs of Lasaxing oilfield in the Daqing Oil Fields complex have geological oil reserves of 1.86 billion tonnes,an oil recovery of 39%,with remaining reserves accounting for more than 45%of the t...The Class-Ⅲ oil reservoirs of Lasaxing oilfield in the Daqing Oil Fields complex have geological oil reserves of 1.86 billion tonnes,an oil recovery of 39%,with remaining reserves accounting for more than 45%of the total geological reserves of the oilfield.Therefore,they have considerable potential for future oil production.The current layered injection technologies fail to achieve effective control over the low single-layer injection rates since they can only produce low throttle differential pressure under low injection rates(5-20 m^(3)/d).In this study,a symmetrically-structured double-offset-hole injection allocator and a novel throttling component were developed.Their spatial layout was constructed and mechanical parameters were optimized using finite element analysis,which allows for expanding the flow rate range at low injection rates.According to experimental results,the throttle differential pressure increased from 0.2 MPa to 0.8 MPa at an injection rate of 5 m^(3)/d,and the range of the single-layer flow rates expanded from 20-70 m^(3)/d to 5-70 m3/d.The field test results show that the effective production of oil layers with medium and low permeability was achieved and that the ratio of producing oil layer thickness to the total reservoir thickness increased by 9.7%on average.Therefore,this study provides valuable technical support for the effective chemical-flooding-based development of Class-Ⅲ oil reservoirs.展开更多
The Daqing exploration area in the northern Songliao Basin has great potential for unconventional oil and gas resources,among which the total resources of tight oil alone exceed 109 t and is regarded as an important r...The Daqing exploration area in the northern Songliao Basin has great potential for unconventional oil and gas resources,among which the total resources of tight oil alone exceed 109 t and is regarded as an important resource base of Daqing oilfield.After years of exploration in the Qijia area,Songliao Basin,NE China,tight oil has been found in the Upper Cretaceous Qingshankou Formation.To work out tight oil’s geological characteristics,taking tight oil in Gaotaizi oil layers of the Upper Cretaceous Qingshankou Formation in northern Songliao Basin as an example,this paper systematically analyzed the geological characteristics of unconventional tight oil in Gao3 and Gao4 layers of the Qijia area,based on the data of the geological survey,well drilling journey,well logging,and test.It is that three sets of hydrocarbon source rocks(K2qn1,K2qn2+3,and K2n1)develop in the examined area,and exhibit excellent type I and II kerogens,high organic matter abundance,and moderate maturity.The reservoir is generally composed of thin-bedded mudstone,siltstone,and sandstone,and presents poor porosity(average 8.5 vol.%)and air permeability(average 4 mD).The main reservoir space primarily includes intergranular pores,secondary soluble pores,and intergranular soluble pores.Three types of orifice throats were identified,namely fine throat,extra-fine throat,and micro-fine throat.The siltstone is generally oil-bearing,the reservoirs with slime and calcium become worse oil-bearing,and the mudstone has no obvious oil-bearing characteristics.The brittleness indices of the sandstone in the tight oil reservoir range from 40%to 60%,and those of the mudstone range from 40%to 45%,indicating a better brittleness of the tight oil reservoir.Based on the study of typical core hole data,this paper gives a comprehensive evaluation of the properties of the tight oil and establishes a tight oil single well composite bar chart as well as the initial evaluation system with the core of properties in the tight oil reservoir.This study has theoretical guiding significance and practical application value for tight oil exploration and evaluation in the Qijia area.展开更多
Low-resistivity oil layers are often missed in logging interpretation because of their resistivity close to or below the resistivity of nearby water layers. Typical low-resistivity oil layers have been found in the pa...Low-resistivity oil layers are often missed in logging interpretation because of their resistivity close to or below the resistivity of nearby water layers. Typical low-resistivity oil layers have been found in the past few years in the Putaohua reservoir of the Puao Oilfield in the south of the Daqing placanticline by detailed exploration. Based on a study of micro-geological causes of low-resistivity oil layers, the macro-geological controlling factors were analyzed through comprehensive research of regional depositional background, geological structure, and oil-water relations combined with core, water testing, well logging, and scanning electron microscopy data. The results showed that the formation and distribution of Putaohua low-resistivity oil layers in the Puao Oilfield were controlled by depositional environment, sedimentary facies, diagenesis, motive power of hydrocarbon accumulation, and acidity and alkalinity of reservoir liquid. The low-resistivity oil layers caused by high bound-water saturation were controlled by deposition and diagenesis, those caused by high free-water saturation were controlled by structural amplitude and motive power of hydrocarbon accumulation. Those caused by formation water with high salinity were controlled by the ancient saline water depositional environment and faulted structure and those caused by additional conductivity of shale were controlled by paleoclimate and acidity and alkalinity of reservoir liquid. Consideration of both micro-geological causes and macro-geological controlling factors is important in identifying low-resistivity oil layers.展开更多
文摘We esta blished our primary theory and method for processing and interpretating the thin in-terbed as an objective exploration.Based on the in-troduction of the maximum likelyhood function of probability statistics,state variable model and re-currence estimation and examination theory,the“SO>ftv ware maximum likelyhood deconvolution’and“DELOP”has been developed.By using it,reflec-tivity with high resolution and high signal/noise ra-tio,minimum phase v wav elets,1 re.lative.interval ve-locities,absolute interval velocities and synthetic.
文摘Introduction
Owing to long-time running, more facilities including stations, pipelines, vessels have become corrosive and aged ,some process has grown old, it has exert more burden for the maintenance and repair.Simultaneously, the fluid production rate, oil production rate and water injection rate has changed greatly so that the inflicts and problems from the established surface systems will become more obvious. Energy cost of production and running has increasing continuously. Capacity has been unbalance in systems and areas.
文摘Many EOR methods have been tested after water flooding in Daqing Oilfield.CO\-2,natural gas, micellar, microbial, steam, polymer and ASP flooding have been tested in the lab and field (some field tests have been performed). Most of the results are good. CO\-2,natural gas,micellar are not suitable to be used in Daqing Oilfield. Polymer flooding of pilots and industrial scale have been successful. The results of polymer flooding are related closely to the injection parameters and injection methods. The incremental oil production are 100 to 140 tons of oil per ton of polymer injected. The oil recovery increased 10% to 14%OOIP. ASP flooding is successful. The cost of chemicals per barrel of incremental oil is $4 0 to $6 2.The incremental recovery is 18% to 20% OOIP over water flooding.
文摘Geodetic deformation severely affects the development of the oilfield and probably causes casing damage or abandonment of injection wells and producers. Therefore, it is meaningful to survey and study three-dimensional geodetic deformation in the process of the oilfield development. In order to study this issue, 11-year long term surveying of three-dimensional geodetic deformation has been carried out while developing Naner area in Daqing oilfield. Basic rules of 3-D geodetic deformation have been obtained through surveying. Results show that production and injection under high pressure may cause the changes of surface elevation, and geodetic deformation correlates with simultaneous formation pressure. Precautions and relative technological measurements have been put forward in the waterflood development in Naner region and provide theoretical guidelines for the production and casing preservation of the oilfield. Finally, surveying results are interpreted by porous elastic theory. Mathematical model to calculate 3-D geodetic deformation is put forward in the course of the oilfield development.
基金funded by China Geological Survey Project(1212011220978)
文摘Daqing Oilfield is located in the northeast of Songnen Plain in Daqing City, Heilongjiang Province, which is a petrochemical industry gathering place based on petroleum refining, chemical industry, chemical fiber and fertilizer. In recent years, the quantity demand of petroleum and petrochemical production for groundwater in Daqing Oilfield is growing, and it's of great significance to analyze and study the quality and pollution degree of groundwater for groundwater exploitation, utilization and protection. In this paper, groundwater quality of Daqing Oilfield evaluated by Nemerow Index is poor, and most points are Class IV groundwater; When evaluating groundwater pollution by hierarchical ladder method, the results show that the severe and extremely severe pollution points account for 34.48% in shallow phreatic water and 20% in deep confined water, showing that shallow groundwater is more seriously polluted than the deep. The main components influencing the quality of groundwater in the study area are total hardness, total dissolved solids, Cl^-, SO_4^(2-) and so on, which are affected by both the native environment and human activities; The main pollution components in groundwater are nitrite and nitrate nitrogen which are affected by human activities. Daqing Oilfield groundwater pollution is characterized by inorganic pollution, while organic components related to human activities contribute less to the groundwater pollution currently.
基金Supported by the China National Science and Technology Major Project(2011ZX05052,2011ZX05010)
文摘By tracking and analyzing the research and practices of chemical flooding carried out in the Daqing Oilfield, NE China since the 1970 s, the chemical flooding theory, technology adaptability and existing problems were systematically summarized, and directions and ideas of development in the future were proposed. In enhanced oil recovery by chemical flooding, the Daqing Oilfield developed theories related to compatibility between crude oil and surfactant that may form ultra-low interfacial tensions with low-acidity oil, and a series of surfactant products were developed independently. The key technologies for chemical flooding such as injection parameter optimization and numerical simulation were established. The technologies of separation injection, cleansing and anti-scaling, preparation and injection, and produced liquid processing were developed. The matching technologies of production engineering and surface facilities were formed. Through implementation of chemical flooding, the Daqing Oilfield achieved outstanding performances with enhanced recovery rate of 12% in polymer flooding and with enhanced recovery rate of 18% in ASP flooding. To further enhance the oil recovery of chemical flooding, three aspects need to be studied:(1) fine characterization of reservoirs;(2) smart and efficient recovery enhancement technologies;(3) environment friendly, high-efficiency and smart matching processes.
文摘Exploration for oil and deep gas in northern Songliao Basin,complex rift basin—Hailaer Basin,and Yi-Shu Graben in peripheral basin has technical challenge.Researches on supporting technology including seismic acquisition,processing and interpretation,logging and drilling are performed to establish high resolution 3D seismic technology for lithologic reservoir,deep volcanic rock and complex rift basin,reservoir evaluation and stimulation technology for low permeability reservoir,volcanic reservoir and complex rift reservoir,and drilling technology for deep volcanic rock,providing technical support for reserves increase in northern Songliao Basin,large gas reservoirs discovery in deep volcanic rock and exploration progress in complex rift basin.Next-step development trend of exploration technology is proposed to meet the demand of more technical challenges in the future.
基金sponsored by the key consulting project of the Chinese Academy of Engineering entitled Research on the Sustainable Development Strategy of China's High Water-cut Old Oilfields(No.2019-XZ-15)the National major project entitled Large Oil and Gas Field and Coalbed Methane Development(No.:2016ZX05010006).
文摘The Class-Ⅲ oil reservoirs of Lasaxing oilfield in the Daqing Oil Fields complex have geological oil reserves of 1.86 billion tonnes,an oil recovery of 39%,with remaining reserves accounting for more than 45%of the total geological reserves of the oilfield.Therefore,they have considerable potential for future oil production.The current layered injection technologies fail to achieve effective control over the low single-layer injection rates since they can only produce low throttle differential pressure under low injection rates(5-20 m^(3)/d).In this study,a symmetrically-structured double-offset-hole injection allocator and a novel throttling component were developed.Their spatial layout was constructed and mechanical parameters were optimized using finite element analysis,which allows for expanding the flow rate range at low injection rates.According to experimental results,the throttle differential pressure increased from 0.2 MPa to 0.8 MPa at an injection rate of 5 m^(3)/d,and the range of the single-layer flow rates expanded from 20-70 m^(3)/d to 5-70 m3/d.The field test results show that the effective production of oil layers with medium and low permeability was achieved and that the ratio of producing oil layer thickness to the total reservoir thickness increased by 9.7%on average.Therefore,this study provides valuable technical support for the effective chemical-flooding-based development of Class-Ⅲ oil reservoirs.
基金funded by the shale oil and gas geological survey project in Quemoco sag,Qiangtang Basin of China Geological Survey(DD20221855,DD20230315).
文摘The Daqing exploration area in the northern Songliao Basin has great potential for unconventional oil and gas resources,among which the total resources of tight oil alone exceed 109 t and is regarded as an important resource base of Daqing oilfield.After years of exploration in the Qijia area,Songliao Basin,NE China,tight oil has been found in the Upper Cretaceous Qingshankou Formation.To work out tight oil’s geological characteristics,taking tight oil in Gaotaizi oil layers of the Upper Cretaceous Qingshankou Formation in northern Songliao Basin as an example,this paper systematically analyzed the geological characteristics of unconventional tight oil in Gao3 and Gao4 layers of the Qijia area,based on the data of the geological survey,well drilling journey,well logging,and test.It is that three sets of hydrocarbon source rocks(K2qn1,K2qn2+3,and K2n1)develop in the examined area,and exhibit excellent type I and II kerogens,high organic matter abundance,and moderate maturity.The reservoir is generally composed of thin-bedded mudstone,siltstone,and sandstone,and presents poor porosity(average 8.5 vol.%)and air permeability(average 4 mD).The main reservoir space primarily includes intergranular pores,secondary soluble pores,and intergranular soluble pores.Three types of orifice throats were identified,namely fine throat,extra-fine throat,and micro-fine throat.The siltstone is generally oil-bearing,the reservoirs with slime and calcium become worse oil-bearing,and the mudstone has no obvious oil-bearing characteristics.The brittleness indices of the sandstone in the tight oil reservoir range from 40%to 60%,and those of the mudstone range from 40%to 45%,indicating a better brittleness of the tight oil reservoir.Based on the study of typical core hole data,this paper gives a comprehensive evaluation of the properties of the tight oil and establishes a tight oil single well composite bar chart as well as the initial evaluation system with the core of properties in the tight oil reservoir.This study has theoretical guiding significance and practical application value for tight oil exploration and evaluation in the Qijia area.
基金supported by the National Natural ScienceFoundation Project(No.40173023)
文摘Low-resistivity oil layers are often missed in logging interpretation because of their resistivity close to or below the resistivity of nearby water layers. Typical low-resistivity oil layers have been found in the past few years in the Putaohua reservoir of the Puao Oilfield in the south of the Daqing placanticline by detailed exploration. Based on a study of micro-geological causes of low-resistivity oil layers, the macro-geological controlling factors were analyzed through comprehensive research of regional depositional background, geological structure, and oil-water relations combined with core, water testing, well logging, and scanning electron microscopy data. The results showed that the formation and distribution of Putaohua low-resistivity oil layers in the Puao Oilfield were controlled by depositional environment, sedimentary facies, diagenesis, motive power of hydrocarbon accumulation, and acidity and alkalinity of reservoir liquid. The low-resistivity oil layers caused by high bound-water saturation were controlled by deposition and diagenesis, those caused by high free-water saturation were controlled by structural amplitude and motive power of hydrocarbon accumulation. Those caused by formation water with high salinity were controlled by the ancient saline water depositional environment and faulted structure and those caused by additional conductivity of shale were controlled by paleoclimate and acidity and alkalinity of reservoir liquid. Consideration of both micro-geological causes and macro-geological controlling factors is important in identifying low-resistivity oil layers.
