Ecological demonstration area (EDA) is an authorized nomination, which should be assessed from several aspects, including ecological, social, environmental, economic ones and so on. It is difficult to advance an exact...Ecological demonstration area (EDA) is an authorized nomination, which should be assessed from several aspects, including ecological, social, environmental, economic ones and so on. It is difficult to advance an exact developing level index of EDA due to its indicator system’s complexity and disequilibrium. In this paper, a framework of indicators was set to evaluate, monitor and examine the comprehensive level of ecological demonstration area (EDA). Fuzzy logic method was used to develop the fuzzy comprehensive evaluation model (FCEM), which could quantitatively reveal the developing degree of EDA. Huiji District of Zhengzhou, Henan Province, one of the 9th group of national EDAs, was taken as a study case. The framework of FCEM for the integrated system included six subsystems, which were social, economic, ecological, rural, urban and accessorial description ones. The research would be valuable in the comprehensive quantitative evaluation of EDA and would work as a guide in the construction practices of Huiji ecological demonstration area.展开更多
The Zhaotong national shale gas demonstration area in Yunnan(hereinafter referred to as demonstration area)is China's third largest national shale gas production base after ChangningeWeiyuan in Sichuan and Fuling ...The Zhaotong national shale gas demonstration area in Yunnan(hereinafter referred to as demonstration area)is China's third largest national shale gas production base after ChangningeWeiyuan in Sichuan and Fuling in Chongqing.And after more than ten years of deep and careful cultivation,a series of important achievements have been obtained in the exploration and development.From the perspective of exploration and development history,theory and technology,this paper systematically summarizes the exploration discovery process and productivity construction progress of shale gas in the demonstration area,expounds the geological exploration theories and key technologies of mountain shale gas,and predicts their development prospect and direction.And the following research results are obtained.First,the exploration and development in the demonstration area has gone through five development stages,and so far,three major productivity construction zones have been formed,including Huangjinba and Zijinba middleedeep shale gas zones and Taiyang shallow shale gas zone,with cumulative proved geological reserves more than 3100×10^(8) m^(3) and cumulative gas production more than 72×10^(8) m^(3).It has been constructed into the third largest green shale gas demonstration base in China.Second,the“multi-field coordination and multi-element coupling”mountain shale gas enrichment,accumulation and occurrence theory of“sedimentary background controlling source rock and reservoir,reworking intensity controlling preservation,and three-dimensional sealing controlling enrichment”is put forward innovatively,and the“three-dimensional sealing system”accumulation model of extrabasinal shallow shale gas is established.Third,a series of zone selection and evaluation technologies for mountain shale gas in strongly reworked complex structural areas have been developed,and the concept of geologyeengineering integration has first been adopted to create transparent shale gas reservoirs and cultivate high-yield wells.A major exploration breakthrough has been achieved from marginal basin medium deep shale gas layers to extrabasin ultra shallow to medium shallow ones,and domestic first large-scale monoblock shallow shale gas field with reserves over 2570×10^(8) m^(3) has been discovered.Fourth,a landmark technological achievement and efficient development model with geologyeengineering integration and shale geomechanical evaluation as the core has been formed,which leads the clean,green and efficient exploration and development of mountain shale gas.In conclusion,it is necessary to implement the exploration strategic idea of“two outgoing”in the demonstration area,i.e.,“walking out of the stable area of the basin and marching into the complex structure areas in the Dianqianbei Depression”and“walking out of the WufengeLongmaxi Formation and exploring other layers for breakthrough”.What's more,it is recommended to carry out the double-layer stereoscopic horizontal well pattern deployment of“Leping Formation CBM(coal measure gas)þLongmaxi Formation shale gas”appropriately in a large scale,so as to establish a new integrated development model for the three-dimensional efficient development of mountain shale gas and CBM.展开更多
Based on analysis of current situation of national marine ecological civilization demonstration areas in China, problems were discussed from aspects of shoreline development, marine disaster waming, marine pollution, ...Based on analysis of current situation of national marine ecological civilization demonstration areas in China, problems were discussed from aspects of shoreline development, marine disaster waming, marine pollution, etc. Afterwards, some development strategies were proposed to provide references for construction of marine ecological civilization demonstration areas in China, thereby promoting overall construction of marine ecological civilization in China.展开更多
Yimeng red culture is an important part of the excellent culture of the Chinese nation.It is of great practical significance and long-term strategic significance to build the demonstration area for the inheritance and...Yimeng red culture is an important part of the excellent culture of the Chinese nation.It is of great practical significance and long-term strategic significance to build the demonstration area for the inheritance and development of Yimeng red culture.Combining digital empowerment with the inheritance and development of Yimeng red culture is a new idea that conforms to the development of the times.In this paper,on the basis of combing Yimeng red cultural resources and combining with the current situation of inheritance and development of Yimeng red culture,the strategic layout and implementation approach of the demonstration area for the inheritance and development of Yimeng red culture were put forward from the perspective of digital empowerment.展开更多
The China Fiber Inspection Bureau has announced that in 2007 it will reinforce the implementation of science, technologies, and standardization, and begin a project of constructing a fiber standardization demonstr... The China Fiber Inspection Bureau has announced that in 2007 it will reinforce the implementation of science, technologies, and standardization, and begin a project of constructing a fiber standardization demonstration area.……展开更多
Since the approval to establishment,the Changning-Weiyuan National Shale Gas Demonstration Area in the Sichuan Basin(hereinafter referred to as Demonstration Area)has been built up into a shale gas industry demonstrat...Since the approval to establishment,the Changning-Weiyuan National Shale Gas Demonstration Area in the Sichuan Basin(hereinafter referred to as Demonstration Area)has been built up into a shale gas industry demonstration base characterized with scale,technology,management and green after more than 10 years of exploration and practice.Its successful experience is of great guiding significance to the efficient development of unconventional oil and gas resources in China.In this paper,the technologies which were developed for the beneficial development of the Demonstration Area during the 13th Five-Year Plan are systematically reviewed and summarized.Then,some countermeasures are proposed to solve the difficulties and challenges to the long-term benefit and stable production of middle-deep shale gas in this area.And the following research results are obtained.First,during the construction of the Demonstration Area,the“three-control”shale gas enrichment and high-production theory is innovatively proposed,and the shale gas enrichment model in the southern Sichuan Basin is clarified.Second,a high-production well cultivation method based on geology-engineering integration is established by developing six main technologies for shale gas exploration and development,which effectively supports the large-scale beneficial development of shale gas in the Demonstration Area.Third,the beneficial development model of middle-deep shale gas in the southern Sichuan Basin is preliminarily formed,and the benefit and efficiency of productivity construction are improved comprehensively.Fourth,the three measures of“controlling the decline rate,enhancing the reserve production and expanding the periphery”are used to support the replacement and stable production of middle-deep shale gas.In conclusion,to sustainably ensure the long-term benefit and stable production of shale gas in the southern Sichuan Basin,it is still necessary to deepen fine reservoir description and complex mechanism understanding and explore EOR technologies.What’s more,the important mean to improve the single-well shale gas production rate in this area is to strengthen the fine fracturing design and implementation under the deep integration of geology and engineering and improve the construction quality of fracturing network continuously.Furthermore,the only way to the low-cost development of the demonstration area is to promote the management reform and innovation continuously and improve the beneficial development model further.展开更多
Casing deformation occurs during the development of ChangningeWeiyuan national shale gas demonstration Area in the Sichuan Basin.In view of this,the correlation between the casing deformation and the geological charac...Casing deformation occurs during the development of ChangningeWeiyuan national shale gas demonstration Area in the Sichuan Basin.In view of this,the correlation between the casing deformation and the geological characteristics as well as hydraulic fracturing was analyzed.It is shown that fracture and bedding(hereinafter collectively referred to as fractures)in faults are the internal cause for casing deformation and hydraulic fracturing is the external cause.Then,the mechanism of casing deformation was clarified.As the fracturing fluid flows along a certain passage into the natural fracture,the pore pressure in the fracture rises.When the critical pressure is reached,the natural fracture is activated to move,and consequently casing deformation occurs.Fluid may flow along three pathways,i.e.,the hydraulic fracture,the axial fracture along the borehole axis created during hydraulic fracturing and the micro-annulus of cement sheath induced by repeated fracturing.Finally,some specific preventive measures were put forward.First,install packers in the whole sections with fractures and beddings.Second,improve the properties of slurry to avoid the formation of micro-annulus of cement sheath.And third,adopt the fracturing technologies to avoid the casing from repeated high pressure.The study results provide the guidance for the solution to shale gas casing deformation.展开更多
The Zhaotong National Shale Gas Demonstration Area along the southern margin of the Sichuan Basin is located in the complex marine tectonic area of South China,where shale deformation and reformation are intense and t...The Zhaotong National Shale Gas Demonstration Area along the southern margin of the Sichuan Basin is located in the complex marine tectonic area of South China,where shale deformation and reformation are intense and the factors controlling sweet spots are complex,so the preservation conditions have an important impact on the enrichment of shale gas.In order to support the selection and evaluation of shale gas sweet spots in this area and improve the success rate of drilling,this paper carried out a geological survey onfield outcrops.Then,based on drilling,mud logging and physical property test data,the structural deformation pattern and the regional deformation characteristics of this demonstration area were analyzed,and the development characteristics of formation joints and fractures,the sealing capacity of shale sur-rounding rock and the distribution characteristics of gas reservoirs were studied.Finally,the preservation conditions of shale gas in the Wufeng Formation of Upper Ordovician and the Longmaxi Formation of Lower Silurian were discussed.And the following research results were ob-tained.First,in the Zhaotong National Shale Gas Demonstration Area,three structural deformation patterns are developed from south to north,including trough type,equal amplitude type and baffle type,which are distributed in three major deformation zones,respectively,i.e.,the shear deformation zone of Central Guizhou Uplift,the compressionetorsion deformation zone of northern YunnaneGuizhou Depression and the compression deformation zone of Southern Sichuan Depression.Second,three types of joints and fractures whose relationships with the di-rection of strata are high angle,middleelow angle and bedding intersection are developed in the WufengeLongmaxi formations and its overlying strata,and their occurrence characteristics are basically consistent with those of the three major deformation zones.Third,the shale of WufengeLongmaxi formations is thick in the north and thin in the south and possesses the preservation conditions of sourceereservoir inte-gration and self-sealing hydrocarbon accumulation.And combined with the sealing ability of the overburden strata and the roof andfloor,its preservation conditions are overall better.Fourth,from the perspective of shale gas component,this area can be divided into three belts,i.e.,methane,methaneþnitrogen mixture and nitrogen from north to south.And the preservation conditions of shale gas are generally better in the north and worse in the south.In conclusion,the shale in the centralenorthern part of Zhaotong National Shale Gas Demonstration Area(compression deformation area and its southern margin)is the most favorable area because of its large shale thickness,weak reformation and deformation,bedding development of joints and fractures,good sealing performance and excellent preservation conditions.The compressionetorsion deformation zone of northern YunnaneGuizhou Depression in the central part is moderate in preservation conditions,and it is the relatively favorable area.The shear deformation zone of Central Guizhou Uplift in the southern part has poor preservation conditions,and it is a prospective area.展开更多
In September 2013,the National Energy Administration approved the establishment of Fuling national shale gas demonstration area(hereinafter referred to as the demonstration area),whose construction was completed in De...In September 2013,the National Energy Administration approved the establishment of Fuling national shale gas demonstration area(hereinafter referred to as the demonstration area),whose construction was completed in December 2015.After nearly one decade of development,it has grown into the main shale gas production base in China.In order to speed up the integration and breakthrough of China's shale gas theoretical understanding and exploration and development technology and effectively promote the great development of marine shale gas in China,this paper reviews and summarizes the development and construction history of the demonstration area,geological theory understanding,engineering technology and key equipment progress.And based on this,the future development direction of the demonstration area is predicted.And the following research results are obtained.First,shale gas exploration and development in the demonstration area is divided into three stages,i.e.,exploration evaluation,phase I and II construction,and stacked development and adjustment.Second,the“binary enrichment”theory for marine shale gas and the engineering theory for efficiently developing gas reservoirs are innovatively established.Third,a series of supporting technologies are innovatively developed,such as optimized and fast drilling technology for shale gas cluster horizontal wells,differentiated network fracturing technology,high-efficiency gas production,gathering and transportation technology,and green development technology for karst mountains,and the localization of key equipment and tools is realized.Fourth,the efficient development of shallow overpressure shale gas reservoirs above 3500 m in depth and the effective development of shale gas reservoirs at the depth of 3500e4000 m are realized in the demonstration area.Fifth,the construction of the demonstration area in the future includes accelerating the development of normal-pressure deep shale gas,continuously tackling key shale gas EOR technologies,actively promoting the field application of new technologies and methods,and powerfully strengthening the construction of green demonstration areas.In conclusion,this demonstration area is the earliest one of four national shale gas demonstration areas,and its achievements will provide continuous guidance for the shale gas exploration and development in China and play a demonstrative and guiding role in promoting the development of shale gas geological theories and exploration and development technologies in China.展开更多
In order to provide a reference for rocky desertification control in karst areas,we take the case of Hongfeng Lake Rocky Desertification Comprehensive Control Demonstration Area in Qingzhen City of Guizhou Province,an...In order to provide a reference for rocky desertification control in karst areas,we take the case of Hongfeng Lake Rocky Desertification Comprehensive Control Demonstration Area in Qingzhen City of Guizhou Province,and expound strength,weakness,opportunity and challenge in its ecological restoration,using SWOT analysis method in management sciences.And we finally put forth scientific strategies for ecological restoration in this demonstration area.展开更多
Based on the field investigations, this paper analyzes systematically the achievements and problems of constructing the demonstrating areas of the ecological rebuilding and economic sustainable development in Hexi, Ga...Based on the field investigations, this paper analyzes systematically the achievements and problems of constructing the demonstrating areas of the ecological rebuilding and economic sustainable development in Hexi, Gansu Province, and then the thoughts on constructing the demonstrating areas are brought forward. It is considered that all kinds of ecological demonstrating areas should be merged in order to construct large scale characterized demonstrating areas which go beyond the district. In other words, in Hexi Region, Zhangye District should be constructed as the largest ecoagriculture demonstrating area of high technology; Wuwei District should be constructed as the largest ecological demonstrating area of agricultural comprehensive exploitation; JiuJia District, which is the shortened form of Jiuquan and Jiayuguan, should be constructed as the largest ecotourism demonstrating area; and Jinchang City should be constructed as the largest ecoindustry demonstrating area. At the same time, the constructing pattern should be selected according to the actual circumstances; science and technology should be applied to construct the demonstrating areas and accelerate the industrialization in the big market. Additionally, it is important to smooth the constructing system and implement the flexible and efficacious running mechanism, and it is suggested that the committee should be organized to administer the ecological demonstrating areas in Hexi Region.展开更多
Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competition focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-...Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competition focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-line hybrid wheat system,which reaches the world leading level in wheat research and has laid an important foundation for the future direction of the world wheat research. Similar to hybrid rice,the innovation of two-line hybrid wheat system is another achievement in science and technology. The application of hybrid wheat in China will greatly increase the food production,and make a great significance to food production and food security. This paper introduces the development process and major breakthrough of hybrid wheat in China,and the main bottleneck and countermeasures in the application of hybrid wheat.展开更多
In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches...In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches such as observation data analysis, meteorological model simulation, and remote sensing, a set of climatic environmental performance assessment methods is developed and established. These methods mainly focus on surface ventilation assessment and urban thermal environment assessment. With the Yanqi Lake ecological development demonstration area located in Huairou district, Beijing as an example, the assessment of the local climatic environment before and after the construction are conducted, and relevant policy suggestions for urban planning and construction are presented. The results show that after development, the ventilation capacity will decrease overall and the ventilation potential index will decrease from 0.53 to 0.44. While this is not a large reduction, and is still at a favorable level, the ventilation potential in some local areas will markedly decrease. Furthermore, the thermal environment will become poorer to some extent; the urban heat island(UHI) area and intensity will increase compared with the current situation;continuous heat islands may occur in local areas; the UHI potential index of the core area will rise from 0.0878 to 0.1217(still a favorable level).Therefore, urban surfaces should be carefully developed and arranged during planning. It is suggested that the negative impacts of large areas of urban construction on the local climatic environment in the Yanqi Lake could be mitigated by 1) strengthening the airflow by introducing fresh,cold, northwesterly air via constructed ventilation corridors, 2) increasing the number of ecological cold sources, particularly for water bodies and green belts to prevent the UHI in the southern region of Yanqi Lake from becoming linked with each other, and 3) considering a pre-program before sub-domain and building planning to obtain optimum building locations. Different construction standards should be developed for different ventilation potential and UHI intensity levels. For strong heat island areas, land areas should be reserved to serve as cold sources.展开更多
In the ChangningeWeiyuan national shale gas demonstration area,SW Sichuan Basin,the wellbore integrity damage occurs in some shale gas wells and has direct effect on the gas production rate of single shale gas horizon...In the ChangningeWeiyuan national shale gas demonstration area,SW Sichuan Basin,the wellbore integrity damage occurs in some shale gas wells and has direct effect on the gas production rate of single shale gas horizontal well.After statistics analysis was performed on the problems related with wellbore integrity,such as casing damage,casing running difficulty and cement sheath blow-by,the multi-factor coupling casing stress calculation and evaluation mode laws established.Then study was conducted on the influential mechanism of multi-factor coupling(temperature effect,casing bending and axial pressure)on casing damage.The shale slip mechanism and its relationship with casing sheared formation were analyzed by using the MohreCoulomb criterion.Inversion analysis was performed on the main controlling factors of casing friction by using the developed casing hook load prediction and friction analysis software.And finally,based on the characteristics of shale gas horizontal wells,wellbore integrity control measures were proposed in terms of design and construction process,so as to improve the drilling quality(DQ).More specifically,shale gas well casing design calculation method and check standard were modified,well structure and full bore hole trajectory design were optimized,drilling quality was improved,cement properties were optimized and cement sealing integrity during fracturing process was checked.These research findings are significant in the design and management of future shale gas borehole integrity.展开更多
When well cementing is conducted in horizontal shale gas wells in Weiyuan block of the Weiyuan-Changning State Shale Demonstration Area,Sichuan Basin,the oil-based drilling fluid is not compatible with cement slurry,i...When well cementing is conducted in horizontal shale gas wells in Weiyuan block of the Weiyuan-Changning State Shale Demonstration Area,Sichuan Basin,the oil-based drilling fluid is not compatible with cement slurry,is difficult to be displaced because of its high density,and cement sheath tends to be broken in the situations of large-scale stimulated reservoir volume fracturing.In view of these problems,a series of studies were carried out specifically on the theoretical basis of cement sheath sealing mechanical parameters,oil-displacement preflush improving the interface cementation quality,toughness set cement satisfying large-scale fracturing requirements and cementing technology conducive to the wellbore integrity.The following achievements were made.First,the theoretical model of cement sheath mechanical integrity taking into account the plastic characteristics and interface cementation strength of cement sheath is instructive to the mechanical design of set cement for horizontal shale gas wells,avoiding the micro-annulus as much as possible.Second,oil-displacement preflush is developed and it is well compatible with oil-based drilling fluids and cement slurry with the flushing efficiency on oil-based drilling fluids higher than 90%.Third,the tough set cement which is developed based on the theoretical model of cement sheath sealing integrity not only guarantees higher compressive strength,but decreases Young's modulus by 30%.Forth,it is confirmed that water displacement cementing technology suitable for shale gas wells is conducive to improving the wellbore seal integrity.These research findings were applied in 12 horizontal wells.It is indicated that the quality cementing ratio of horizontal segment reaches 92%and the post fracturing effect is very good,which guarantees the sealing integrity of wellbores and provides a technical support for the highly efficient development of shale gas reservoirs.展开更多
In this paper,shale gas cores from the Lower Silurian Longmaxi Formation in the Zhaotong National Shale Gas Demonstration Area were selected to study the hydration effect of differentfluids on the fracture morphology ...In this paper,shale gas cores from the Lower Silurian Longmaxi Formation in the Zhaotong National Shale Gas Demonstration Area were selected to study the hydration effect of differentfluids on the fracture morphology inside the shale,the rock tensile strength and the Brazilian tensile failure mode.Fresh water and slick water were adopted for hydration pretreatments and the CT technique was used to compare the changes of the fabric in the shale.Then,Brazilian tensile tests were carried out to study the tensile strength and tensile failure modes of the shale specimen after hydration pretreatment.Finally,two horizontal wells in the study area were selected to perform pilot tests of hydration pre-treatment in their fracturing operation sites.And the following research results were obtained.First,in the process of spontaneous imbibition,the hydration effect of fresh water is superior to that of slick water in promoting the fracture complexity of marine shale in the same hydration duration.Second,fresh water has greater surface tension and lower viscosity and its hydration effect can not only promote the propagation of original fractures but induce new micro-fractures or branches,while the hydration effect of slick water mainly promotes the propagation of original fractures.Third,due to hydration effect,marine shale is damaged and its tensile strength is reduced.After the hydration pretreatment by fresh water and slick water,the tensile strength of the shale specimens are reduced by 35.6%and 18.1%,respectively.Fourth,according to the propagation paths of main fractures,the Brazilian tensile failure modes of hydrated shale can be divided into four types(i.e.,step shaped,dog-leg shaped,branching shaped and arc shaped)or their combinations,while the tensile failure mode of unhydrated shale is only a straight line.Fifth,hydration effect can effectively increase the complexity of the hydraulic fractures in marine shale,so if the conditions permit,it is recommended to inject a certain amount of fresh water at a high pumping rate within the limited pressure after perforation and to shut in the well until the hydraulic fracturing operation.And in order to reduce the difficulties of pumping the proppant during the hydraulic fracturing operation,a pumping strategy of“low proppant concentration,large volume of slurries”can be adopted to reach the expected proppant volume.展开更多
基金U nder the auspices of the M ajor State B asic R esearch D evelopm ent Program of C hina (973 Program ) (N o.2005C B 724205)
文摘Ecological demonstration area (EDA) is an authorized nomination, which should be assessed from several aspects, including ecological, social, environmental, economic ones and so on. It is difficult to advance an exact developing level index of EDA due to its indicator system’s complexity and disequilibrium. In this paper, a framework of indicators was set to evaluate, monitor and examine the comprehensive level of ecological demonstration area (EDA). Fuzzy logic method was used to develop the fuzzy comprehensive evaluation model (FCEM), which could quantitatively reveal the developing degree of EDA. Huiji District of Zhengzhou, Henan Province, one of the 9th group of national EDAs, was taken as a study case. The framework of FCEM for the integrated system included six subsystems, which were social, economic, ecological, rural, urban and accessorial description ones. The research would be valuable in the comprehensive quantitative evaluation of EDA and would work as a guide in the construction practices of Huiji ecological demonstration area.
基金Project supported by the Scientific Research and Technology Development Project PetroChina Company Limited“Research on microscopic characteristics and enrichment mechanism of shallow shale gas reservoirs in Zhaotong”(No.2021DJ1903)“Field test of downhole fiber intelligent monitoring technology”(No.2020F-44).
文摘The Zhaotong national shale gas demonstration area in Yunnan(hereinafter referred to as demonstration area)is China's third largest national shale gas production base after ChangningeWeiyuan in Sichuan and Fuling in Chongqing.And after more than ten years of deep and careful cultivation,a series of important achievements have been obtained in the exploration and development.From the perspective of exploration and development history,theory and technology,this paper systematically summarizes the exploration discovery process and productivity construction progress of shale gas in the demonstration area,expounds the geological exploration theories and key technologies of mountain shale gas,and predicts their development prospect and direction.And the following research results are obtained.First,the exploration and development in the demonstration area has gone through five development stages,and so far,three major productivity construction zones have been formed,including Huangjinba and Zijinba middleedeep shale gas zones and Taiyang shallow shale gas zone,with cumulative proved geological reserves more than 3100×10^(8) m^(3) and cumulative gas production more than 72×10^(8) m^(3).It has been constructed into the third largest green shale gas demonstration base in China.Second,the“multi-field coordination and multi-element coupling”mountain shale gas enrichment,accumulation and occurrence theory of“sedimentary background controlling source rock and reservoir,reworking intensity controlling preservation,and three-dimensional sealing controlling enrichment”is put forward innovatively,and the“three-dimensional sealing system”accumulation model of extrabasinal shallow shale gas is established.Third,a series of zone selection and evaluation technologies for mountain shale gas in strongly reworked complex structural areas have been developed,and the concept of geologyeengineering integration has first been adopted to create transparent shale gas reservoirs and cultivate high-yield wells.A major exploration breakthrough has been achieved from marginal basin medium deep shale gas layers to extrabasin ultra shallow to medium shallow ones,and domestic first large-scale monoblock shallow shale gas field with reserves over 2570×10^(8) m^(3) has been discovered.Fourth,a landmark technological achievement and efficient development model with geologyeengineering integration and shale geomechanical evaluation as the core has been formed,which leads the clean,green and efficient exploration and development of mountain shale gas.In conclusion,it is necessary to implement the exploration strategic idea of“two outgoing”in the demonstration area,i.e.,“walking out of the stable area of the basin and marching into the complex structure areas in the Dianqianbei Depression”and“walking out of the WufengeLongmaxi Formation and exploring other layers for breakthrough”.What's more,it is recommended to carry out the double-layer stereoscopic horizontal well pattern deployment of“Leping Formation CBM(coal measure gas)þLongmaxi Formation shale gas”appropriately in a large scale,so as to establish a new integrated development model for the three-dimensional efficient development of mountain shale gas and CBM.
文摘Based on analysis of current situation of national marine ecological civilization demonstration areas in China, problems were discussed from aspects of shoreline development, marine disaster waming, marine pollution, etc. Afterwards, some development strategies were proposed to provide references for construction of marine ecological civilization demonstration areas in China, thereby promoting overall construction of marine ecological civilization in China.
基金Sponsored by the Achievements of Social Science Planning Research Project of Shandong Province(22CYMJ11)Phased Achievements of the key project of the Party School of Shandong Provincial Committee of the Communist Party of China(Shandong Administration College).
文摘Yimeng red culture is an important part of the excellent culture of the Chinese nation.It is of great practical significance and long-term strategic significance to build the demonstration area for the inheritance and development of Yimeng red culture.Combining digital empowerment with the inheritance and development of Yimeng red culture is a new idea that conforms to the development of the times.In this paper,on the basis of combing Yimeng red cultural resources and combining with the current situation of inheritance and development of Yimeng red culture,the strategic layout and implementation approach of the demonstration area for the inheritance and development of Yimeng red culture were put forward from the perspective of digital empowerment.
文摘 The China Fiber Inspection Bureau has announced that in 2007 it will reinforce the implementation of science, technologies, and standardization, and begin a project of constructing a fiber standardization demonstration area.……
基金supported by the National Major Science and Technology Project“Changning-Weiyuan shale gas development demonstration project”(No.2016ZX05062)the Major Science and Technology Project of PetroChina Company Limited“Research and application of key technologies for producing 30 billion cubic meters of natural gas in Southwest Oil and Gas Field”(No.2016E-0611).
文摘Since the approval to establishment,the Changning-Weiyuan National Shale Gas Demonstration Area in the Sichuan Basin(hereinafter referred to as Demonstration Area)has been built up into a shale gas industry demonstration base characterized with scale,technology,management and green after more than 10 years of exploration and practice.Its successful experience is of great guiding significance to the efficient development of unconventional oil and gas resources in China.In this paper,the technologies which were developed for the beneficial development of the Demonstration Area during the 13th Five-Year Plan are systematically reviewed and summarized.Then,some countermeasures are proposed to solve the difficulties and challenges to the long-term benefit and stable production of middle-deep shale gas in this area.And the following research results are obtained.First,during the construction of the Demonstration Area,the“three-control”shale gas enrichment and high-production theory is innovatively proposed,and the shale gas enrichment model in the southern Sichuan Basin is clarified.Second,a high-production well cultivation method based on geology-engineering integration is established by developing six main technologies for shale gas exploration and development,which effectively supports the large-scale beneficial development of shale gas in the Demonstration Area.Third,the beneficial development model of middle-deep shale gas in the southern Sichuan Basin is preliminarily formed,and the benefit and efficiency of productivity construction are improved comprehensively.Fourth,the three measures of“controlling the decline rate,enhancing the reserve production and expanding the periphery”are used to support the replacement and stable production of middle-deep shale gas.In conclusion,to sustainably ensure the long-term benefit and stable production of shale gas in the southern Sichuan Basin,it is still necessary to deepen fine reservoir description and complex mechanism understanding and explore EOR technologies.What’s more,the important mean to improve the single-well shale gas production rate in this area is to strengthen the fine fracturing design and implementation under the deep integration of geology and engineering and improve the construction quality of fracturing network continuously.Furthermore,the only way to the low-cost development of the demonstration area is to promote the management reform and innovation continuously and improve the beneficial development model further.
基金supported by the National Major Science and Technology Project“Factory drilling techniques and integrated application”(No.2016ZX05022001)CNPC Major Shale Gas Project“Shale gas drilling and production engineering field tests”(No.2014F-4702-05).
文摘Casing deformation occurs during the development of ChangningeWeiyuan national shale gas demonstration Area in the Sichuan Basin.In view of this,the correlation between the casing deformation and the geological characteristics as well as hydraulic fracturing was analyzed.It is shown that fracture and bedding(hereinafter collectively referred to as fractures)in faults are the internal cause for casing deformation and hydraulic fracturing is the external cause.Then,the mechanism of casing deformation was clarified.As the fracturing fluid flows along a certain passage into the natural fracture,the pore pressure in the fracture rises.When the critical pressure is reached,the natural fracture is activated to move,and consequently casing deformation occurs.Fluid may flow along three pathways,i.e.,the hydraulic fracture,the axial fracture along the borehole axis created during hydraulic fracturing and the micro-annulus of cement sheath induced by repeated fracturing.Finally,some specific preventive measures were put forward.First,install packers in the whole sections with fractures and beddings.Second,improve the properties of slurry to avoid the formation of micro-annulus of cement sheath.And third,adopt the fracturing technologies to avoid the casing from repeated high pressure.The study results provide the guidance for the solution to shale gas casing deformation.
基金supported by the National Major Science and Technology Project"Zhaotong Shale Gas Exploration&Development Demonstration Project"(No.2017ZX05063)CNPC Major Field Test Project"Research and Test of Key Effective Expoitation Techniques of Deep Shale Gas"(No.:2019F-13)。
文摘The Zhaotong National Shale Gas Demonstration Area along the southern margin of the Sichuan Basin is located in the complex marine tectonic area of South China,where shale deformation and reformation are intense and the factors controlling sweet spots are complex,so the preservation conditions have an important impact on the enrichment of shale gas.In order to support the selection and evaluation of shale gas sweet spots in this area and improve the success rate of drilling,this paper carried out a geological survey onfield outcrops.Then,based on drilling,mud logging and physical property test data,the structural deformation pattern and the regional deformation characteristics of this demonstration area were analyzed,and the development characteristics of formation joints and fractures,the sealing capacity of shale sur-rounding rock and the distribution characteristics of gas reservoirs were studied.Finally,the preservation conditions of shale gas in the Wufeng Formation of Upper Ordovician and the Longmaxi Formation of Lower Silurian were discussed.And the following research results were ob-tained.First,in the Zhaotong National Shale Gas Demonstration Area,three structural deformation patterns are developed from south to north,including trough type,equal amplitude type and baffle type,which are distributed in three major deformation zones,respectively,i.e.,the shear deformation zone of Central Guizhou Uplift,the compressionetorsion deformation zone of northern YunnaneGuizhou Depression and the compression deformation zone of Southern Sichuan Depression.Second,three types of joints and fractures whose relationships with the di-rection of strata are high angle,middleelow angle and bedding intersection are developed in the WufengeLongmaxi formations and its overlying strata,and their occurrence characteristics are basically consistent with those of the three major deformation zones.Third,the shale of WufengeLongmaxi formations is thick in the north and thin in the south and possesses the preservation conditions of sourceereservoir inte-gration and self-sealing hydrocarbon accumulation.And combined with the sealing ability of the overburden strata and the roof andfloor,its preservation conditions are overall better.Fourth,from the perspective of shale gas component,this area can be divided into three belts,i.e.,methane,methaneþnitrogen mixture and nitrogen from north to south.And the preservation conditions of shale gas are generally better in the north and worse in the south.In conclusion,the shale in the centralenorthern part of Zhaotong National Shale Gas Demonstration Area(compression deformation area and its southern margin)is the most favorable area because of its large shale thickness,weak reformation and deformation,bedding development of joints and fractures,good sealing performance and excellent preservation conditions.The compressionetorsion deformation zone of northern YunnaneGuizhou Depression in the central part is moderate in preservation conditions,and it is the relatively favorable area.The shear deformation zone of Central Guizhou Uplift in the southern part has poor preservation conditions,and it is a prospective area.
基金supported by the Science and Technology Research Project of China Petroleum&Chemical Corporation“Research on technology for enhancing the recovery in Fuling Shale Gas Field”(No.P22183).
文摘In September 2013,the National Energy Administration approved the establishment of Fuling national shale gas demonstration area(hereinafter referred to as the demonstration area),whose construction was completed in December 2015.After nearly one decade of development,it has grown into the main shale gas production base in China.In order to speed up the integration and breakthrough of China's shale gas theoretical understanding and exploration and development technology and effectively promote the great development of marine shale gas in China,this paper reviews and summarizes the development and construction history of the demonstration area,geological theory understanding,engineering technology and key equipment progress.And based on this,the future development direction of the demonstration area is predicted.And the following research results are obtained.First,shale gas exploration and development in the demonstration area is divided into three stages,i.e.,exploration evaluation,phase I and II construction,and stacked development and adjustment.Second,the“binary enrichment”theory for marine shale gas and the engineering theory for efficiently developing gas reservoirs are innovatively established.Third,a series of supporting technologies are innovatively developed,such as optimized and fast drilling technology for shale gas cluster horizontal wells,differentiated network fracturing technology,high-efficiency gas production,gathering and transportation technology,and green development technology for karst mountains,and the localization of key equipment and tools is realized.Fourth,the efficient development of shallow overpressure shale gas reservoirs above 3500 m in depth and the effective development of shale gas reservoirs at the depth of 3500e4000 m are realized in the demonstration area.Fifth,the construction of the demonstration area in the future includes accelerating the development of normal-pressure deep shale gas,continuously tackling key shale gas EOR technologies,actively promoting the field application of new technologies and methods,and powerfully strengthening the construction of green demonstration areas.In conclusion,this demonstration area is the earliest one of four national shale gas demonstration areas,and its achievements will provide continuous guidance for the shale gas exploration and development in China and play a demonstrative and guiding role in promoting the development of shale gas geological theories and exploration and development technologies in China.
基金Guizhou Science and Technology Plan Project(S20071061)Social Public Relations Plan Project of Guizhou Provincial Department of Technology(SY20113096)Guizhou Philosophy and Social Sciences Plan Project(11GZQN19)
文摘In order to provide a reference for rocky desertification control in karst areas,we take the case of Hongfeng Lake Rocky Desertification Comprehensive Control Demonstration Area in Qingzhen City of Guizhou Province,and expound strength,weakness,opportunity and challenge in its ecological restoration,using SWOT analysis method in management sciences.And we finally put forth scientific strategies for ecological restoration in this demonstration area.
文摘Based on the field investigations, this paper analyzes systematically the achievements and problems of constructing the demonstrating areas of the ecological rebuilding and economic sustainable development in Hexi, Gansu Province, and then the thoughts on constructing the demonstrating areas are brought forward. It is considered that all kinds of ecological demonstrating areas should be merged in order to construct large scale characterized demonstrating areas which go beyond the district. In other words, in Hexi Region, Zhangye District should be constructed as the largest ecoagriculture demonstrating area of high technology; Wuwei District should be constructed as the largest ecological demonstrating area of agricultural comprehensive exploitation; JiuJia District, which is the shortened form of Jiuquan and Jiayuguan, should be constructed as the largest ecotourism demonstrating area; and Jinchang City should be constructed as the largest ecoindustry demonstrating area. At the same time, the constructing pattern should be selected according to the actual circumstances; science and technology should be applied to construct the demonstrating areas and accelerate the industrialization in the big market. Additionally, it is important to smooth the constructing system and implement the flexible and efficacious running mechanism, and it is suggested that the committee should be organized to administer the ecological demonstrating areas in Hexi Region.
文摘Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competition focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-line hybrid wheat system,which reaches the world leading level in wheat research and has laid an important foundation for the future direction of the world wheat research. Similar to hybrid rice,the innovation of two-line hybrid wheat system is another achievement in science and technology. The application of hybrid wheat in China will greatly increase the food production,and make a great significance to food production and food security. This paper introduces the development process and major breakthrough of hybrid wheat in China,and the main bottleneck and countermeasures in the application of hybrid wheat.
基金sponsored by Beijing Municipal Science and Technology Project(Z131100001113026)the Program of the Research and Innovation Team on Urban Climate Assessment of Beijing Meteorological Bureau,Climate Change Special Foundation of China Meteorology Administration(CCSF201506)+1 种基金Science and technology project of Beijing Meteorological Bureau(BMBKJ201402002)National Natural Science Foundation of China(71473146)
文摘In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches such as observation data analysis, meteorological model simulation, and remote sensing, a set of climatic environmental performance assessment methods is developed and established. These methods mainly focus on surface ventilation assessment and urban thermal environment assessment. With the Yanqi Lake ecological development demonstration area located in Huairou district, Beijing as an example, the assessment of the local climatic environment before and after the construction are conducted, and relevant policy suggestions for urban planning and construction are presented. The results show that after development, the ventilation capacity will decrease overall and the ventilation potential index will decrease from 0.53 to 0.44. While this is not a large reduction, and is still at a favorable level, the ventilation potential in some local areas will markedly decrease. Furthermore, the thermal environment will become poorer to some extent; the urban heat island(UHI) area and intensity will increase compared with the current situation;continuous heat islands may occur in local areas; the UHI potential index of the core area will rise from 0.0878 to 0.1217(still a favorable level).Therefore, urban surfaces should be carefully developed and arranged during planning. It is suggested that the negative impacts of large areas of urban construction on the local climatic environment in the Yanqi Lake could be mitigated by 1) strengthening the airflow by introducing fresh,cold, northwesterly air via constructed ventilation corridors, 2) increasing the number of ecological cold sources, particularly for water bodies and green belts to prevent the UHI in the southern region of Yanqi Lake from becoming linked with each other, and 3) considering a pre-program before sub-domain and building planning to obtain optimum building locations. Different construction standards should be developed for different ventilation potential and UHI intensity levels. For strong heat island areas, land areas should be reserved to serve as cold sources.
基金Special and Significant Project of China National Petroleum Corporation for Shale Gas“On-site Tests of Drilling&Production Engineering for Shale Gas”(No.:2014F-4702-05).
文摘In the ChangningeWeiyuan national shale gas demonstration area,SW Sichuan Basin,the wellbore integrity damage occurs in some shale gas wells and has direct effect on the gas production rate of single shale gas horizontal well.After statistics analysis was performed on the problems related with wellbore integrity,such as casing damage,casing running difficulty and cement sheath blow-by,the multi-factor coupling casing stress calculation and evaluation mode laws established.Then study was conducted on the influential mechanism of multi-factor coupling(temperature effect,casing bending and axial pressure)on casing damage.The shale slip mechanism and its relationship with casing sheared formation were analyzed by using the MohreCoulomb criterion.Inversion analysis was performed on the main controlling factors of casing friction by using the developed casing hook load prediction and friction analysis software.And finally,based on the characteristics of shale gas horizontal wells,wellbore integrity control measures were proposed in terms of design and construction process,so as to improve the drilling quality(DQ).More specifically,shale gas well casing design calculation method and check standard were modified,well structure and full bore hole trajectory design were optimized,drilling quality was improved,cement properties were optimized and cement sealing integrity during fracturing process was checked.These research findings are significant in the design and management of future shale gas borehole integrity.
基金Project supported by the National Key Basic Research Program of China(973 Program),“Basic Study on High-efficiency Development of Marine Shale Gas in South China(Part 3“Key Basic Study on Drilling and Completion of Horizontal Shale Gas Wells”)”(Grant No.2013CB228003).
文摘When well cementing is conducted in horizontal shale gas wells in Weiyuan block of the Weiyuan-Changning State Shale Demonstration Area,Sichuan Basin,the oil-based drilling fluid is not compatible with cement slurry,is difficult to be displaced because of its high density,and cement sheath tends to be broken in the situations of large-scale stimulated reservoir volume fracturing.In view of these problems,a series of studies were carried out specifically on the theoretical basis of cement sheath sealing mechanical parameters,oil-displacement preflush improving the interface cementation quality,toughness set cement satisfying large-scale fracturing requirements and cementing technology conducive to the wellbore integrity.The following achievements were made.First,the theoretical model of cement sheath mechanical integrity taking into account the plastic characteristics and interface cementation strength of cement sheath is instructive to the mechanical design of set cement for horizontal shale gas wells,avoiding the micro-annulus as much as possible.Second,oil-displacement preflush is developed and it is well compatible with oil-based drilling fluids and cement slurry with the flushing efficiency on oil-based drilling fluids higher than 90%.Third,the tough set cement which is developed based on the theoretical model of cement sheath sealing integrity not only guarantees higher compressive strength,but decreases Young's modulus by 30%.Forth,it is confirmed that water displacement cementing technology suitable for shale gas wells is conducive to improving the wellbore seal integrity.These research findings were applied in 12 horizontal wells.It is indicated that the quality cementing ratio of horizontal segment reaches 92%and the post fracturing effect is very good,which guarantees the sealing integrity of wellbores and provides a technical support for the highly efficient development of shale gas reservoirs.
基金Project supported by the National Major Science and Technology Project“Zhaotong Shale Gas Exploration and Development Demonstration Project”(No.2017ZX05063)the Science and Technology Project of CNPC Chuanqing Drilling Engineering Company Limited“Study and Application of Hydration Mechanism of Shale Reservoir”(No.CQ2018B-23-1-4).
文摘In this paper,shale gas cores from the Lower Silurian Longmaxi Formation in the Zhaotong National Shale Gas Demonstration Area were selected to study the hydration effect of differentfluids on the fracture morphology inside the shale,the rock tensile strength and the Brazilian tensile failure mode.Fresh water and slick water were adopted for hydration pretreatments and the CT technique was used to compare the changes of the fabric in the shale.Then,Brazilian tensile tests were carried out to study the tensile strength and tensile failure modes of the shale specimen after hydration pretreatment.Finally,two horizontal wells in the study area were selected to perform pilot tests of hydration pre-treatment in their fracturing operation sites.And the following research results were obtained.First,in the process of spontaneous imbibition,the hydration effect of fresh water is superior to that of slick water in promoting the fracture complexity of marine shale in the same hydration duration.Second,fresh water has greater surface tension and lower viscosity and its hydration effect can not only promote the propagation of original fractures but induce new micro-fractures or branches,while the hydration effect of slick water mainly promotes the propagation of original fractures.Third,due to hydration effect,marine shale is damaged and its tensile strength is reduced.After the hydration pretreatment by fresh water and slick water,the tensile strength of the shale specimens are reduced by 35.6%and 18.1%,respectively.Fourth,according to the propagation paths of main fractures,the Brazilian tensile failure modes of hydrated shale can be divided into four types(i.e.,step shaped,dog-leg shaped,branching shaped and arc shaped)or their combinations,while the tensile failure mode of unhydrated shale is only a straight line.Fifth,hydration effect can effectively increase the complexity of the hydraulic fractures in marine shale,so if the conditions permit,it is recommended to inject a certain amount of fresh water at a high pumping rate within the limited pressure after perforation and to shut in the well until the hydraulic fracturing operation.And in order to reduce the difficulties of pumping the proppant during the hydraulic fracturing operation,a pumping strategy of“low proppant concentration,large volume of slurries”can be adopted to reach the expected proppant volume.
