Table of Content

28 February 2012, Volume 33 Issue 1

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Sealing capacity of the Ordovician carbonate rocks in Tazhong area, the Tarim Basin

Qian Yixiong, He ZhiLiang, Chen Qianglu, Li Huili, Lu Qinghua, Cai Xierao, You Donghua

2012, 33(1):  1-9,18.  doi:10.11743/ogg20120101

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Mineral composition,micro-pore characteristics and well-logs from five wells were used to study the sealing capacity of the Ordovician carbonate rocks in Tazhong area,Tarim Basin.The Ordovician Lianglitage and Yingshan formations are at substage A-B of the middle diagenetic stage and substage A of the late diagenetic stage.For the Lianglitage Formation grainstone,the breakthrough pressure (BP) is 1.81-29.76 MPa,and the threshold radius (TR) is 13.89-77.35 nm,.For the marlstones,the BP is 14.33MPa and TR is 25.9-44.51 nm.For the micritic limestone with band of argillite,the BP is 0.98-10.35 MPa and the TR is 13.52-142.60 nm.The BP and the TR of the Yingshan Formation limy dolomites are 0.98-10.35 MPa and 13.52-142.60 nm.Thus,the marlstone and partial grainstone of the Lianglitage Formation and the Yingshan Formation dolomite limestone have certain sealing capacity,with thickness over 5 m,BP over 5 MPa,TR between 10-20 nm,pore throat radium less than 0.1 μm.In addition,the tight interval consisted of dolomite limestone with high resistivity of 4-10 m thick in the Yingshan Formation is thought to be local caprocks in Tazhong area.Its existence is one of the main factors resulting in the oil/gas distribution pattern in the Ordovician Yingshan Formation in Zhong-1 well,i.e.oil in its upper part and gas in its lower part.

Types and hydrocarbon generation potential of the Permian source rocks in the Sichuan Basin

Liu Quanyou, Jin Zhijun, Gao Bo, Zhang Dianwei, Xu Mei’e, Tang Ruipeng

2012, 33(1):  10-18.  doi:10.11743/ogg20120102

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Based on samples from outcrops and cores,we analyzed various geochemical parameters such as elemental component,Rock-Eval and carbon isotopes of the Permian source rocks.The kerogens of the Permian source rocks are dominated by type Ⅱ,with local occurrence of type Ⅰ and/or Ⅲ kerogens.Their hydrocarbon generation capacity is determined by the total organic carbon(TOC)and Rock-Eval parameters.In general,mudstones have a higher TOC,and greater potential for hydrocarbon generation than limestones.We restored the hydrocarbon generation potentials of marine mudstonse and limestones with high thermal maturity,which is necessary for the evaluation of the highly mature source rocks in South China.The Permian source rocks in Sichuan Basin are generally of high thermal maturity at high to post mature stages.During the Early Cretaceous,the Permian source rocks entered into peak hydrocarbon generation and contributed to late gas accumulation in the upper marine assemblage in South China.

Meso-Cenozoic volcanic rock distribution and reservoir characteristics in the Bohai Bay Basin

Jin Chunshuang, Qiao Dewu, Dan Weining

2012, 33(1):  19-29,36.  doi:10.11743/ogg20120103

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Bohai Bay Basin underwent two rifting cycles during the Mesozoic and Cenozoic era,accompanied by intense neutral-acidic and neutral-basaltic magmatism.Based on comprehensive research of the Meso-Cenozoic volcanic rock distribution and their reservoir types,characteristics and patterns,this paper discusses the exploration potential of volcanic hydrocarbon reservoirs in Bohai Bay Basin.The Mesozoic,especially the Early Cretaceous volcanic rock is mainly distributed in the east of the basin;the Cenozoic magmatism may be divided into four stages:Kongdian-Sha⁴,Sha³,Sha²-Dongying,Guantao.There are three types of volcanic hydrocarbon reservoirs in the basin,i.e.buried-hill,fault block and stratigraphic-lithologic hydrocarbon reservoirs.The first type is mainly developed in the Mesozoic volcanic rocks; the second type is mainly developed in the volcanic rocks of Kongdian-Sha⁴ stage; the third type is common in the Cenozoic volcanic rocks,of which the effusive facies are the most favorable for reservoir formation.The Sha³ volcanic rocks e contribute to the greatest volume of proven reserves.In addition to the Sha³ volcanic rocks the Mesozoic,Kongdian-Sha⁴ and offshore Sha²-Dongying volcanic rocks also show great potential for petroleum exploration.

Mesozoic bottom boundary unconformity and its significance for hydrocarbon exploration in the Yakela faulted uplift, Tarim Basin

Luo Xiaolong, Tang Liangjie, Xie Daqing, Luo Shuanghan, Jiang Huashan, Yang Yong, Chen Xuyun

2012, 33(1):  30-36.  doi:10.11743/ogg20120104

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Mesozoic bottom boundary in Yakela Faulted upliftt is an important unconformity developed for a long geologic time,and its overlying and underlying formations are quite different in deformation manner.Based on interpretation of 3D seismic data in the Yakela faulted uplift,combining with well data,regional geology and regional strata distribution characteristics,the types of unconformities related to this reflector can be divided into nonconformity,truncation unconformity,overlap unconformity and karst unconformity according to their formation mechanisms and main factors controlling geometry.The nonconformities mainly occur in the eastern and western parts,where the pre-Mesozoic deposits were denuded completely.The monocline area,fold area and fault-fold area of truncation unconformity exsit in the middle and western parts of the Yakela faulted uplift from west to east.The overlap unconformity distributes along south climb of the Yakela faulted upliftt.The karst unconformity mainly distributes in the central and western parts,where the upper Palaeozoic was eroded completely and carbonates expose.The unconformities are of great significance for hydrocarbon accumulation as they can act as migration pathway,improve reservoir conditions and create lots of traps.Comprehensive analysis of the characteristics and distribution patterns of various unconformities in this area reveals that they are the results of tectonic deformations strong in the east and weak in the west of the Yakela faulted uplift.

Reservoir bitumen genesis and its impacts on hydrocarbon migration and accumulation:a case study from Chang 8¹ of Yangchang Fomation in Huaqing area,the Ordos Basin

Chen Shijia, Yao Jingli, Lu Jungang, Yang Guoping, Wen Yanchun, Zhang Jizhi, Shi Zhenghao

2012, 33(1):  37-44.  doi:10.11743/ogg20120105

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Bitumen is common in the pores of Chang 8¹ pay zone of the Triassic Yanchang Formation in Huaqing area of the central part of Ordos Basin,and the oil-water relationship is very complicated.According to the analysis on the geochemical characteristics of reservoir extracts and crude oil,combining with comparative test on the reservoir physical property of cores containing bitumen before and after washing oil and the reservoir fluorescence analysis,authors studies in detail the reservoir bitumen genesis and its impact on reservoir physical property and hydrocarbon migration and accumulation in this area.The results show that the genesis of reservoir bitumen and crude oil are different,and the bitumen has lower maturity with strong biodegradation.Base on the experiment of washing oil,it is found that both the post-washing porosity and permeability of cores containing bitumen increase significantly,and the oil formed in late stage mainly distributes in the residual pore filled with bitumen.It is pointed out that bitumen has an important control on reservoir physical property and hydrocarbon migration and accumulation at late stage.The Chang 8¹ formation experienced hydrocarbon two accumulation stages,the first stage happened in Middle-Late Jurassic and the second in Early Cretaceous.The early accumulated crude oil with low maturity suffered from strong biodegradation and were turned to bitumen,which filled in the pores of reservoir together with chlorites and ferrocalcites,making the reservoir tighter.The mature oil generated from the source rocks in late stage could only accumulate in the residual pores filled with bitumen or in pores of reservoir with less bitumen.

Relationship between sedimentary microfacies and reservoir productivity in Da12-Da66 wellblock,Daniudi gas field

Liu Shuanglian, Li Hao, Zhou Xiaoying

2012, 33(1):  45-49,60.  doi:10.11743/ogg20120106

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Based on sediment supplies,sedimentary hydrodynamic conditions,channel structures and features,the paper discusses the relationship between the vertical/lateral structures of the sedimentary microfacies and reservoir productivity in Da12-Da66 wellblocks,Daniudi gas field.The result indicates that the combinations of source supplies and sedimentary hydrodynamic conditions affectes the vertical distribution of reservoir productivity.Under the condition of abundant sediment supplies,stable and strong hydrodynamic conditions,the formations are mostly payzones with medium to high productivity.Reservoirs in the central part of distributary channel microfacies have been commonly tested relatively stable productivity and are mostly payzones with medium to high productivity.In contrast,reservoirs at the edge of distributary channel have been usually tested with the feature of unstable productivity.The payzones with medium to high productivity grow usually in the intersection of two channels with strong hydrodynamic conditions.In addition,because of complexity of meander channel and great shape changes,it is difficulty to identify and discover.Generally,productivity is lower for unstable channel except for areas with strong hydrodynamic conditions.The study results coincide with the production tests in Da12-Da66 wellblocks.

Significance of syndepositional volcanism to high quality reservoirs in the Xujiahe Formation,the western Sichuan Depression

Zeng Xiaoying, Zhang Juan, Liu Yuanyang, Li Yong

2012, 33(1):  50-60.  doi:10.11743/ogg20120107

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The Xujiahe Formation is a regional gas reservoir in western Sichuan Depression.Due to the great bu- rial depth,the reservoir generally experienced complicated diagenesis,resulting in tight to supertight reservoirs.Even so,porous reservoirs with relatively good storage capacity were also developed.From observation of more than 30 wells,over 7 000 ordinary thin sections and over 1 000 cast thin sections in the study area as well as the research of related reservoirs,it is demonstrated that volcanic debris dissolved pores are the major storage space of sandstones of of the 2nd and 4th member of Xujiahe Formation,and are the major controlling factor of high quality reservoirs in the area.Dissolution of feldspar deposited through weathering and transportation of parent rock is not the major reason for the forming of sandstone with medium-high porosity.Volcanic debris from syndepositional volcanic eruption contain many "soluble compositions",which tend to be dissolved and devitrified to form pores during diagenesis,thus controlling the distribution of high-permeability sandstone reservoirs with well-developed secondary dissolved pores.Therefore,the compositions of debries from the syndepositional volcanism and their dissolution intensity are the major factors controlling the development and distribution of high quality reservoirs of the Xujiahe Formation and the formation of sandstone with medium-high porosity.Ganzi-Litang inter-continental rift area where volcanisms were strong during the Late Triassic was the major source for volcanic debris in the study area.

Carbonate reservoir prediction technology and its application in Ka-1 3D acreage in Tazhong area,Tarim Basin

Yang Jiangfeng, Guan Da, Zhu Wenbin, Zhang xuedong, Xiang Xuemei, Wu Dali

2012, 33(1):  61-69.  doi:10.11743/ogg20120108

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Previous exploration and research results show that the carbonate reservoir spaces of the Ordovician Yingshan Formation in Ka-1 3D acreage in Tazhong area are dominated by fractures and dissolution pores.However,recent reprocessed seismic data reveal some bead-shaped and short-axis-shaped high amplitude anomalies in Ka-1 3D seismic data.For this reason,many techniques,such as numeral seismic forward modeling,incoherence detection,palaeogeomorphology restoration and multiple seismic attribute extraction,are integrated to re-predict the Ordovician YingShan Formation carbonate reservoirs in Ka-1 3D acreage.The results show that the zig-shaped strong amplitude anomalies in plane view represent igneous rocks,while strong amplitude anomalies being scattered in plane view and beads-shaped on profile represent carbonate reservoirs with large cavities.These interpretations have been verified by well W20 completed recently.

High resolution sequence stratigraphy and sedimentary characteristics of the Middle-Lower Cambrian in Bachu Uplift,the Tarim Basin

Liu Zhongbao, Yang Shengbin, Jiao Cunli, Cai Xiyao, Xing Xiujuan, Wang Enhui

2012, 33(1):  70-76.  doi:10.11743/ogg20120109

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The Cambrian is of large burial depth and few exploration wells in Tarim Basin,The specific lithologic assemblage consisting of intebedded evaporites,carbonate rocks and bronzing mudstones in the moddle-lower Camberan is analyzed using sequence stratigraphy and sedimentology theories.We suggest that clay contents of GR within the depositional system can not reflect the relative sea level change,and that fine sedimentary facies division is key to base-level cycle identification.The Cambrian is divided into 3 supersequences and 7 third-order sequences,among which 4 third-order sequences occur in the Middle-Lower Cambrian and 3 in the Upper Cambrian.In addition,the features of each third-order sequence are analyzed and an isochronous stratigraphic framework is built for the Cambrian.The sedimentary environments of the Middle-Lower Cambrian in Bachu Uplift are evaporate platform and restricted platform,where 2 sedimentary facies,5 subfacies and 19 microfacies are identified.The Lower Cambrian is mainly of restricted platform deposits dominated by lime flat,limestone-dolomite flat,gypsum-dolomite flat and dolomite flat deposition.In Bachu Uplift,the gypsum-dolomite flat deposits dominate in the west and dolomite flat deposits in the east.In contrast,the major sedimentary facies of the Middle Cambrian is evaporate platform dominated by intertidal flat and saline lacustrine deposits.Taking the Ba3-Ba1 wells as the line of demarcation,the Middle Cambrian is mainly of supertidal flat deposits to its west,and is dominated by intertidal flat and salt lake deposits to its east.

Single sand body identification in compound distributary channel of delta plain:a case study from the fourth member of Quantou Formation in the southern part of central Fuyu oilfield

Feng Congjun, Bao Zhidong, Shan Qitong, Sun Mengsi, Yu Shiyan, Duan Hongzhen

2012, 33(1):  77-83.  doi:10.11743/ogg20120110

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Taking the fourth member of Quantou Formation(K₁q⁴) in the southern part of central Fuyu oilfield as an example,we systematically identified single sand bodies in the compound distributary channels of delta plain based on study of sedimentary microfacies with integrating various data including cores,well logging and production performance.The results show that K₁q⁴ has well-developed large interconnected and banded compound distributary channel sand bodies of various origins in the study area.Detail characterization of single sand bodies reveals that there are 6 main superposition patterns,including multi-layers,overlapping,multi-boundaries,single-boundary,juxtaposition and isolation.Moreover,8 types of logging-facies marks of single sand bodies are identified for vertical timing and lateral boundary identification.The dense well pattern and small well spacing data in the study area are used to establish a quantitative prediction model for the width-thickness ratio of single sand bodies.By using this model,totally 44 single sand bodies of low sinuous meandering type are recognized in the 5^th to 10^th layers of K₁q⁴.These single sand bodies show a SW-NE trending banded distribution with a width of 150-500 meters,a thickness of 2-8 meters,and a width-thickness ratio of 40-100.Tracer test results prove the accuracy of single sand body identification.

Characteristics and genesis of dolomitization in Changxing and Feixianguan Formations in Panlongdong,northeastern Sichuan Basin

Chen Qi, Hu Wenxuan, Li Qing, Zhu Jingquan

2012, 33(1):  84-93.  doi:10.11743/ogg20120111

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Systematic field investigation and thin section observation as well as electron microprobe determination reveal that dolomitization is common in the Changing and Feixianguan formations in Panlongdong,northeastern Sichuan Basin.Various types of dolomites are developed and distributed vertically in obvious zonation.From bottom to top,they are biological clasitic dolomite,reef dolomite,crystalline dolomite,oolitic dolomite and micrite dolomite respectively.Our study showed that three genetic models could account for the formation process of the dolomites,including mixed-water dolomitization,infiltration and circumfluence dolomitization as well as penecontemporaneous dolomitization.The biological clasitic and reef dolomites were mainly formed through the mixed-water dolomitization,which occurred in relatively open diagenesis environment with meteoric water input.These dolomites had different δ¹³C values and more negative δ¹⁸O values and remained original sedimentary structure of rocks which restricted dolomitization.The infiltration and circumfluence dolomitization resulted in the formation of the crystalline and oolitic dolomites which have same δ¹³C values,less negative δ¹⁸O valuse,Fe and Mn contents.The penecontemporaneous dolomitization created the micrite dolomite with tight lithology and less negative δ¹³C and δ¹⁸O values.

Application of experimental design theory in stochastic reservoir model optimization

Chong Renjie, Yu Xinghe, Li Tingting

2012, 33(1):  94-100,110.  doi:10.11743/ogg20120112

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To improve the conventional reservoir model optimization techniques,this paper presents a method to introduce experimental design theory to uncertainty reservoir modeling optimization.First,we identified the dominant nondeterministic variables that influence the OOIP calculation and their probability distributions by the actual oilfield data analysis,and made a modeling plan through experimental design.And then,several deterministic models were built to calculate OOIP.Multiple regression was performed on the nondeterministic variables and the OOIP calculated with corresponding models.Finally,the Monte Carlo simulation was run to obtain the OOIP probability curve and P10,P50 and P90 model parameters,which were used to establish the reference P10,P50 and P90 models.This method is not only more objective and efficient,but also capable of identifying the key geologic uncertainties that influence the OOIP calculation and provides a new way to evaluate the uncertainty of OOIP.

Carbonate reservoir characteristics and their genetic mechanisms in Tazhong83-Tazhong16 wellblock,Tarim Basin

Yang Jun, Jiang Zhenxue, Xiang Caifu, Wang Hongping

2012, 33(1):  101-110.  doi:10.11743/ogg20120113

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The Lower Paleozoic marine carbonate reservoirs in Tazhong83-Tazhong16 wellblock in Tazhong uplift within Tarim Basin have multiple oil/gas-bearing horizons,great differences in hydrocarbon properties and complicated oil/gas-water contact.On the basis of current hydrocarbon reservoir characteristics in the study area,in conjunction with the hydrocarbon accumulation process in Tazhong uplift,we analyzed the genetic mechanism of "the Himalayan gas invasion's decisive influence on current nature and distribution of hydrocarbon reservoirs" from the viewpoint of dynamic hydrocarbon migration,and drew three conclusions: (1) Hydrocarbon pools in the same horizon but different areas show the characteristics of "gas at both ends and oil in the middle" due to the existence of multiple faults connected with gas sources; (2) Hydrocarbon pools in the same area but at different horizons show the characteristics that "pure gas change progressively into condensate gas and finally into oil from bottom to top due to the limited gas charge along faults connected with gas sources and the heterogeneity of carbonate reservoirs; (3) Hydrocarbon pools in the same horizon and same area show abrupt change of oil/gas-water contact due to the local structural configuration and the existence of tight barriers.It is believed that the faults connected with gas source and unconformities that serve as the dominant hydrocarbon migration pathways control the direction of hydrocarbon migration,while the local structure configuration and tight barriers confine the extent of hydrocarbon migration.They both are the major factors controlling the nature of hydrocarbon reservoirs and the oil/gas-water contact.It is estimated that the deeper the exploration targets are and the closer they are to the faults connected with gas sources,the more favorable they are to gas exploration.

Progress and prospects of enhanced oil recovery technologies at home and abroad

Ji Bingyu

2012, 33(1):  111-117.  doi:10.11743/ogg20120114

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This paper summarizes the development of enhanced oil recovery(EOR)at home and abroad,focusing on improved waterflooding,heavy oil thermal recovery,chemical flooding,gas injection,microbial enhanced oil recovery and physical oil recovery.Nowadays,the first four technologies have been widely applied in oilfields,while the latter two technologies are still in researching and testing.Based on a thorough analysis of the foreign experiences and specific geologic conditions in China,this paper presents the focuses of future research and development tendency of EOR.For the improved waterflooding,the focuses are establishing a reasonable and effective injection-production system and realizing uniform control of displacement profile by strata subdivision and recombination,stereo optimization of well pattern and type.For the heavy oil thermal recovery,the key is to improve heavy oil reservoir development efficiency by using wells with complicated structure,steam and various additives.For the gas injection,the scale of its application is widening and CCS projects will increase gradually with greenhouse gas emissions cuts requirement.For the chemical flooding,the trend is toward application in reservoirs with high temperature and high salinity,reservoirs with high permeability channels and post polymer flooding reservoirs.

Resevoir evaluation and development strategies of Daniudi tight sand gas field in the Ordos Basin

Hou Ruiyun, Liu Zhongqun

2012, 33(1):  118-128.  doi:10.11743/ogg20120115

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Daniudi gas field in Ordos Basin is typical tight sand gas reservoirs with low permeability,low pressure and low production rate.It has been a challenge to develop this kind of gas field economically.This paper cove- rs lithofacies,lithology,petrophysical property,pore structure and gas bearing potential of different formations.On this basis,four types of reservoirs have been identified.In terms of production rate,TypeⅠis the highest,followed by Type Ⅱand then Type Ⅲ,while Type Ⅳ has no productivity.According to the types and distribution of reservoirs,different development strategies have been adopted.Single layer production through vertical well fits TypeⅠ,whose porosity and permeability are better,net pay is thicker and production rate is higher.Commingled system through vertical well for overlapped layers suits Type Ⅱ,whose porosity and permeability are moderate,net pay is thinner and production rate of single layer is lower.Staged fracturing through horizontal well matches both Type Ⅱand Type Ⅲ with only one widely distributing layer.Applying different development strategies to different types of reservoirs,we has succeeded in improving the individual-well production rate and achieving economical development of this gas field.Annual production capacity of 25×10⁸ m³ has been built up there.

Study on effectiveness of integrating well pattern rearrangement with binary combination flooding in oil reservoirs with high water-cut: an example from the IV5-11 layers in Shuanghe oilfield,the Nanxiang Basin

Ai Jingxu, Zhou Shengyou, Ma Yan, Xiao jian, Dai Yahong, Li Hongsheng, Hui Guanzhou

2012, 33(1):  129-134.  doi:10.11743/ogg20120116

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It is difficult to significantly enhance oil recovery of reservoirs with high water-cut at late production period.This paper presents a successful example to demonstrate the effectiveness of integrating well pattern rearrangement with binary combination flooding in Shuanghe oilfield.Based on the overlap of pay zones and differences of their petrophysical properties,as well as the large vertical production performance variation from one pay zone to the another,we rearranged the well pattern through layer series subdivision and recombination in similarity principle,adjusted injection & production system and designed horizontal infill wells.According to the characteristics of the reservoirs and balancing economic benefits,binary combination flooding was carried out in the major pay zones while water flooding adjustment was performed in the other non-major pay zones.The injection parameters of binary combination flooding were optimized by using the orthogonal design method.Study results indicate that this technique can improve the recovery factor greatly,with amplitude of 2.19[WTXT]%[WTBZ] higher than the sum of well pattern rearrangement and binary combination flooding.

Application conditions of seismic waveform classification technique and its use in the study of sedimentary microfacies of Pubei area

Jiang Qingchun, Wang Hai, Li Dan, Cao Feng, Li Qiufen, Sun Zuoxing, Zhou Hui

2012, 33(1):  135-140.  doi:10.11743/ogg20120117

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During analyzing the seismic facies of Qiketai(Qkt) Formation in Pubei(Pb) area with Stratimagic software,we compared the application conditions of waveform classification technique.Seismic data with a frequence greater than 40 Hz and a signal-to-noise ratio greater than 25 DB are suitable for seismic waveform classification.The effect of waveform analysis is good in area with gentle structural attitude and under-developed fractures.Furthermore,the selection of suitable seismic time window and the setting of proper waveform classification number also affect the application effect of waveform classification technique.Generally,a waveform classification number of five to eight is reasonable,which match well with the sedimentary microfacies types.This technique is used to map the sedimentary microfacies of Qkt Group.Comparison with single well sedimentary microfacies identification shows that the coincidence rate is more than 86%,verifying the reliability of sedimentary microfacies prediction by using seismic waveform classification technique.Finally,this paper presents the sandstone distribution predicted by using this technique which can be used to guide future exploration of subtle reservoirs in the area.

Analysis on bin size of seismic survey and lateral resolution of imaging

Guo Kai, Tong Zhaoqi, Teng Houhua

2012, 33(1):  141-147.  doi:10.11743/ogg20120118

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Based on the analyses of general bin size design of seismic survey,the imaging of forward modeling with different trace spacing verifies that interpretation results are quite different for different tracing spacing.The larger the trace spacing is,the more difficult the interpretation is,and the greater the error is.The smaller the trace spacing is,the closer the interpretation results are to the real geologic structures.Analyses of real seismic imaging with different bin sizes reveal that event-crossing may occur on imaging section of fault when bin size is large,making it very difficult to accurately identify fault.In contrast,imaging section of fault is narrow and clear when bin size is small,making it easy to interpret fault,thus increasing lateral resolution of seismic data.In conjunction with the previous exploration application and according to the geologic task in different seismic exploration stages,we present corresponding proposals of bin sizes for seismic exploration in frontier area,high resolution seismic exploration,seismic exploration during rolling exploration and development.

Strategic replacement of oil producing area in Russia-former Soviet Union and its enlightenment

Zhang Kang, Dong Li, Wen Youjian

2012, 33(1):  148-158.  doi:10.11743/ogg20120119

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The life cycle of a single oil/gas field is limited,therefore the sustainable production of oil and gas relies on two replacements: the first is tactic replacement,i.e.reserves and production growth in mature oil/gas field (area);the other is strategic replacement,i.e.frontier exploration and development including new domains,new reservoir types,new plays.From Tsarist Russia to the former Soviet Union and to Russia,oil producing areas experienced a close replacement from the first to the second and to third Baku,which provides a good case study for the research on the strategic replacement of production area in China.The analysis of oil production change before and after the breakup of former Soviet Union demonstrates that transferring investment needed for the tactic and strategic replacement from oil industry to other political and economic areas is the major factor influencing the sustainable development of its petroleum industry.If Russia do not reform,open-up and raise enough funds from both domestic and abroad channels now,it will be hard to guarantee the sustainable development of oil industry,the increasing of oil export and the realization of the original objective of "enriching country via oil and gas".The oil production objective rules require us to strengthen the willingness and activeness of tactic and strategic replacement,and continue to "aggressively" realize the sustainable development of oil industry.Finally,the paper proposes the prerequisite to realize strategic replacement: new strategic exploration concept based on the reality,new exploration and development technologies adapted to the complex play and hard conditions,investment guarantee and certain time cycle.