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    20 June 2008, Volume 30 Issue 3
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    专家论坛
    OPTIMIZATION TECHONOGY AND THE APPLICATION OF GEL BREAKING OF LARGE SCALE FRACTURING BASED ON THE FLUID CONCENTRATED THEORY
    OPTIMIZATION TECHONOGY AND THE APPLICATION OF GEL BREAKING OF LARGE SCALE FRACTURING BASED ON THE FLUID CONCENTRATED THEORY
    2008, 30(3):  1-3.  DOI: 10.3863/j.issn.1000-2634.2008.03.001
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    Aiming at the tight sandstone reservoirs in which,there is poor porous and permeability condition,large scale fracturing is the effective way to improve the development effect.Because the conventional technology of gel breaker addition amount can not satisfy the higher requirements of gel breaking,a new optimization technology of fracturing fluid gel breaking is proposed which is on the basis of considering concentration effect caused by filtration of the fracturing fluid in the formation.Through simulating the temperature field of fracture,gel breaking test under the different temperature condition and considering the gel breaking after concentration of fracturing fluid filtration,it is suggested that on the spot of large scale fracturing gel breaker addition amount should be higher than conventional amount,as to be able to ensure the gel breaking effect of the large scale fracturing,to realize the quick flowing back,decrease damage.The new gel breaking optimization is applied successfully in large scale fracturing,the technology is successfully applied in well CX491155.6 m3 fracturing,the flowback efficiency is 74.9% after 7hours opening well and flowback fluid is intensive.Testing recovery rate increase to 14×104m3/d (the wellhead pressure is 22MPa) from 0.2×104m3/d after perforation.The technology is popularized gradually in large scale fracturing in Weston Sichuan.
    地质勘探
    S WAVE IN ACOUSTIC ANISOTROPIC MEDIA
    WANG Xiaohuan
    2008, 30(3):  4-7.  DOI: 10.3863/j.issn.1000-2634.2008.03.002
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    Acoustic VTI media is a kind of model which is artificially defined as a velocity VS0 for shear wave on symmetry axis.Contrary to the conventional theory that whenVS0 equals to zero,shear wave is eliminated,the existence of acoustic VTI media is demonstrated and its properties examined.Specifically,it is pointed out that SV wave generally has finite nonzero phase and group velocities in acoustic VTI media.This phenomenon can be observed in fullwave field simulation,which,however,was concluded as artificial numerical pseudomorph in the past.The most obvious characteristic of acoustic VTI media is extreme anisotropy,which under certain circumstances would present infinite anisotropy.Several fullwave field simulations have been established for different acoustic VTI media models,by adopting the finite deference method with highorder crossed grids,the x,zcomponents of group velocity and phase velocity are calculated respectively when VS0 is given different values.The following wave performance can be achieved through comparison and analysis,the polarization direction of Vwave propagating vertically in acoustic VTI media parallels to that of Pwave propagating in the same direction,amplitude of SVwave is large due to concentration of energy in the vicinity of the symmetry axis,the group velocities of Pwave and SVwave can be very close or even equal to each other.
    OIL MIGRATION ORIENTATION OF ORDOVICIAN IN TAZHONG UPLIFT
    GUO Jian-jun;CHEN Jian-fa;WANG Tie-guan;ZHOU Xue-hui;LI Cheng-shan
    2008, 30(3):  8-13.  DOI: 10.3863/j.issn.1000-2634.2008.03.003
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    Definition of oil migration orientation has great importance to further oil exploration.Based on the previous research,it is found out that it is incorrect that the northwest Tazhong uplift was higher and the southeast uplift was lower from Caledonian to middle Hercynian.In general,southeast part of the uplift is the highest part all along,and there are two relatively higher parts in Tazhong,one is located near well Zhong1 in west Tazhong horst,the another,the highest part in Tazhong,is located near Tazhong well1 in east Tazhong horst.The correlation of oil source indicates the crude oil of Ordivician in Tazhong mainly came from the source rocks in middle to upper Ordivician.According to ancient structural setting,the study on filling and accumulating orientation of the crude oil from middle to upper Ordivician shows that there are at least two orientations of oil migration in north Tazhong slope,one is from lower noetheast Tazhong to higher southeast Tazhong,another is from lower northwest Tazhong to higher Zhong well1block.The oil and gas in Tazhong well52,Zhong well4 in south Tazhong slope came from Tanggubasi sag in south Tazhong and migrated a relatively short distance,which further proves the hydrocarbon source rocks in middle to upper Ordivivian in Tanggudasi sag are of good oil and gas generation potential.
    PROBE OF THE SCALE OF PALAEO RESERVOIR IN SILURIAN,TARIM BASIN
    WANG Xian-dong;JIANG Zhen-xue;PANG Xiong-qi;ZHANG Jun;
    2008, 30(3):  13-16.  DOI: 10.3863/j.issn.1000-2634.2008.03.004
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    There are extensive bituminous sandstones in Silurian in Tarim Basin,which means substantive hydrocarbon was accumulated in Silurian in geological time and which also illustrates the palaeo reservoir accumulated early in Silurian was badly destroyed.To correctly evaluate remaining resources of Silurian and carry out further exploration in Silurian,it is very important for us to fully understand the scale of palaeo reservoir in Silurian.The distribution characteristics,forming process and mechanism of Silurian bituminous sandstones and the forming pattern of early Silurian reservoir are established,and the study results show that palaeo reservoir in Silurian are not so large on scale as imagined and not giant selfcontained reservoir,there are only some big pools distributing in partial uplifts of precarboniferous.
    PROBE INTO SUBLACUSTRINE FAN OF TRIASSIC IN AKEKULE AREA,TARIM BASIN
    LIU Chen-sheng;GUO Jian-hua;ZHU Rui
    2008, 30(3):  17-19.  DOI: 10.3863/j.issn.1000-2634.2008.03.005
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    Based on the observation of cores,grain sizes of the middle oil member are coarser in Akeyasu area at northern study area of Triassic,and the lithologies include conglomerate and pebbled sandstone.The compounds of pebbles are complicated with significantly various grain sizes and poor sorting,the sediments are supported by matrix,and Bouma sequences are well developed.Integrated with analysis of logging data and seismic data,the sedimentary facies of northern Akekule area are confirmed as sublacustrine fan.The fan can be divided into three subfacies that include middle fan,fringe fan and canyon,the middle fan is the principal part,in which,the depositional grain sizes are the coarsest,the middle fan can be divided into braided channels and interchannels mircrofacies.Fringe fan is distributed outmost of sublacustrine fan,being transitional belt between sublacustrine fan and basin.Canyons are transportation way of terrestrial source area for sublacustrine fan,and the main deposition is sandstone （pebble） and mudstone,logging data presents twostage positive rhythm layers,the feature is corresponding with depositional characteristic of sublacustrine fan.Sandstones of canyon and middle fan is all favorable petroleum accumulation bodies in the area.
    论文
    STRUCTURE RIDGE AND HYDROCARBON MIGRATION PATHWAY SYSTEM OF PALEOZOIC IN AKEKULE LOBE
    LI Kun;ZHAO Xi-kui;ZHANG Xiao-bing;DAI Han-song
    2008, 30(3):  20-23.  DOI: 10.3863/j.issn.1000-2634.2008.03.006
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    The consequence of exploration shows the Akekule lobe has complicated pathway systems and resource rocks which have been providing hydrocarbon in Paleozoic due to many tectonic movements during the long period.On the basis of analyzing route,capability and function of path systems,the systems can be divided into three types,i.e.,fault,unconformity and karst network.By reconstructing the paleo tectonic structure with seismic data and well information and recognizing the dynamic process of oilgas migration,the research points out that the local big faults are the main paths of vertical hydrocarbon transportation.The research also concludes that the superposition of unconformities（T47,T07,T06）are the key factors of horizontal hydrocarbon migration,furthermore,the geometrical formation during the critical period of hydrocarbon gathering,especially the distribution of paleo ridge,determines the predominant direction and path of hydrocarbon migration.The types of pathway systems of hydrocarbon migration by faultunconformitykarst network along structure ridge in the form of threedimensional laddershaped are the most distinct characteristic in work area.
    地质勘探
    HYDROCARBON MIGRATION PATHWAY IN LENGHUNANBAXIAN STRUCTURAL BELT,THE NORTHERN QAIDAM BASIN
    QU Jiang-xiu;GAO Chang-hai;ZHA Ming
    2008, 30(3):  24-28.  DOI: 10.3863/j.issn.1000-2634.2008.03.007
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    The practice of hydrocarbon exploration in LenghuNanbaxian structural belt,the northern Qaidam Basin,shows that there are mainly three types of hydrocarbon migration pathways within the studied area,connected sand bodies and unconformityes are lateral migration pathways and faults are vertical migration pathways.The hydrocarbon migration pathways and their relationship with hydrocarbon accumulation are studied by synthetically applying the theories and methods of modern hydrocarbon accumulation and geophysics,geology,seismics,logging and analysis assay data.The results show that the types of hydrocarbon migration pathways and the assembly patterns are main control factors for hydrocarbon migration,accumulation and poolforming.This research approaches the control of the transport layers(unconformity,connected sand body,fault and its assembly pattern) on hydrocarbon migration,accumulation and poolforming and relationship with hydrocarbon formation and distribution,which can guide the practice of hydrocarbon exploration.
    THE RERECOGNITION OF STRATIGRAPHIC TRAP ACCUMULATION IN MADONG AREA
    YIN Tai-ju;ZHANG Chang-min;WANG Li-qun;CHEN Yan;YANG Ming-lin
    2008, 30(3):  29-32.  DOI: 10.3863/j.issn.1000-2634.2008.03.008
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    The drilling of Madong well1 results in new recognition of hydrocarbon accumulation potential around Guqiu sag,Jungger basin and gives lessons and experience to stratigraphic hydrocarbon exploration in the area.The expected drilling mission is not reached duo to inadequate hydrocarbon source and poorly identified traps.Recent research indicates there are only under developed hydrocarbon source rocks thin thickness and localized distribution in the sag,which greatly confines the sufficiency of the traps.The cap rocks of penetrated traps are of poor sealing capacity and sufficiency,there are severe uncertainty of the traps.Formation of the reservoirs for the traps will be hard due to inadequate hydrocarbon source,explorative targets for stratigraphic traps should turn to the favorable hydrocarbon capturing areas in migrating channels in south and north rims of Mahai.
    GENETIC MODEL OF PERMIANTRIASSIC STRUCTURES IN CHISHUI AREA
    SU Pei-dong;QIN Qi-rong;HUANG Run-qiu;HU Ming
    2008, 30(3):  33-36.  DOI: 10.3863/j.issn.1000-2634.2008.03.009
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    The Permian and Triassic are the most important gasproducing formations in Chishui area,Guizhou province.The exploration of reservoirs in this area has been confined for a long time because the understanding of structure formulation and evolvement are unclear.Based on the analyses of large amount of data,main research results are proposed.The structures of the Permian and Triassic in Chishui area developed under the background of development of Sichuan basin.The EWtrending structures formed earlier and the NStrending structure later.The earlier EWtrending structures formed because of the structural compaction pressure of the Qianzhong palaeohigh to north while the later NStrending structures formed by the south induced stress action of the westnorthern structural stress in the east boundary of Sichuan basin.The EWtrending structures (especially,great EWtrending faults) generated anticlockwise smooth shearing activity in the NS structural movement stage due to the WStrending structural stress action.
    CONDITIONS OF GAS ACCUMULATION AND PROSPECTION POTENTIAL OF SHALLOWMID CLASTIC STRATA IN CHISHUI SAG
    XIE Gang-ping;XIA Bin;WANG Liang-jun;HU Dong-feng
    2008, 30(3):  37-41.  DOI: 10.3863/j.issn.1000-2634.2008.03.010
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    Chishui sag is one of the regions with relativelylow degree of exploration.On the basis of regional petroleum geology study,the strata and depositional features are analyzed,and the conditions of gas accumulation and prospection potential of shallowmid clastic strata in Chishui depression and its adjacent areas are discussed in detail from the view point of gas source rocks,reservoir beds,seal,their combination and factors of accumulation in this paper.It is concluded that although in the Xujiahe formation in lower Jurassic and upper Triassic system there is some potential of hydrocarbon generation,the Silurian Longmaxi formation and the Permian Longtan formation are the main gas source,the gas reservoirs in the second and the forth members of Xujiahe formation and lower Shaximiao formation exhibit polyphase migration and accumulation and are adjusted and modified,finally formed in Himalia stage,the gas was from continental and marine facies and generated in older and lower strata but stored up in later and upper strata,the favorable gas accumulation belts lie in the GuanduTiantangba and BaoyuanXuebaiping regions,and are also the favorable belts of a whole body including upper and lower strata,continental and marine facies together considered,and spatial exploration in Chishui and its adjacent area.
    GENESIS IDENTIFICATION AND PROBE OF DEPOSITIONAL MODEL OF TURBIDITE
    MA Quan-hua;
    2008, 30(3):  42-44.  DOI: 10.3863/j.issn.1000-2634.2008.03.011
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    For the less exploration of deep water turbidite reservoir in eastern sag of Liaohe Basin,the sedimentary type of the sand stones is analyzed by using two types of grain size discriminant function and genesis illustration in the article.Grain size analysis data is applied to distinguished the sedimentary environment of holoclastic rock by the discriminant function.The genesis illustration can reflect the change law of energy and flowability of clastic deposits during the sedimentary process.So,the the sedimentary environment of holoclastic rocks can be judged accurately by using the two ways.In this article,the glutenite of Oulituozi oilfield in Shasan middle section is judged as the turbidite deposition by using these methods,and then the depositional model of the sand stone is also discussed.
    THE EVALUATION METHOD OF LACUSTRINE SUBAQUEOUS FAN LITHOLOGIC RESERVOIR IN RIFT BASIN
    CAO Zheng-lin;DENG Yi-lin;SHI Lan-ting;ZHANG Li-ping
    2008, 30(3):  45-49.  DOI: 10.3863/j.issn.1000-2634.2008.03.012
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    The lacustrine subaqueous fan lithologic reservoirs are the main new type of the reserve volume growth in rift basis in Middle and East China,the distribution is controlled by the extention of lacustrine subaqueous fans.The typical characteristics of the lacustrine subaqueous fan lithologic reservoirs are narrow extention,quick horizontal change and strong inhomogeneity.Murige lacustrine subaqueous fan lithologic reservoir in Erlian Basin in China is taken as example to discuss the reservoir evaluation thought,method and main content from the estimated reserves to proven reserves,present some measures in view of verifying the reserve volume accurately and reasonably,and decrease the risk of evaluation exploration.The study shows that the key of lacustrine subaqueous fan lithologic reservoir evaluation is the change of the reservoir characteristics,dynamical evaluation of the main characteristics of lacustrine subaqueous fan lithological reservoir must be done,such as net pay thickness,porosity and saturation etc.,on the basis of dynamic reservoir prediction.By the abovelmentioned reservoir evaluation thought and method,good application effectiveness in the Murige lacustrine subaqueous fan lithological reservoir in Erlian Basin is acquired.
    THE GEOCHEMICAL CHARACTERISTIC ＆ ORIGIN OF CARBONIFEROUS IN TIANCHIPU STRUCTURE
    LI Yan-jun;PU Hong-guo;FU Xiao-wen;DENG Liu-ping;FENG Qing-ping
    2008, 30(3):  50-54.  DOI: 10.3863/j.issn.1000-2634.2008.03.013
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    The natural gas of Tianchipu in the east Sichuan Basin is dry gas,with the characteristic of thermal cracking petroleum gas,meanwhile it consists of a little higher evolution kerogen cracking gas.It is a kind of higher carbon isotope,condensed oil,made up by light hydrocarbons almostly.This kind of oil hasn′t been biodegraded.By researching carbon isotope,light hydrocarbon,petroleum and source rocks biomarkers.It is pointed out that the gas and oil of carboniferous are sapropeltype with a higher maturity index,all are from lower Silurian source rocks.The study shows that natural gas is different from the coal gas from late Permian epoch.The formation of higher carbon isotope is petroleum thermal cracking and retrograde condensation.The geochemistry analysis of oil reservoir demonstrates that in the Carboniferous beds in Tianchipu,there exist the ancient reservoirs of Indo Chinese epoch.According to bury,thermal cracking history and geothermal gradient,it is known that the oil accumulated in Carboniferous changed to gasoil reservoir at late Cretaceous period.This research systematically describes that gas reservoirs of Carboniferous in the eastern Sichuan basin belong to paleoreservoir cracking origin,and provides a scientific basis for exploring oil cracked gas in the east Sichuan Basin.
    BLIND SEPARATION OF CONVOLVED MIXTURES BY USING ONEUNIT ALGORITHM IN THE FREQUENCY DOMAIN
    XIONG Ying
    2008, 30(3):  55-57.  DOI: 10.3863/j.issn.1000-2634.2008.03.014
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    The convolutive model in the time domain is transformed to an instantaneous model in the frequency domain by sliding window shorttime Fourier Transform,so more robust ICA algorithm of instantaneous model can be employed to solve convolved mixtures problem.In this paper,based on blind convolved mixtures algorithm in the frequency domain,a complex fixed point algorithm that is a oneunit algorithm of the fast convergence is applied to every frequency bin,it can separate source signals under separation filter higher order in the real environment.Then in order to prevent it from converging to the same signal,the deflation technique is used to extract the separated signals from convolved mixtures in the frequency domain.Scaling and permutation problems also are solved in the frequency domain,so multiplesources can be recovered one by one.Simulation demonstrates the validity.
    CORRECTING METHOD OF NEUTRON LOGGING IN CASED WELL
    LUO Li;MENG Ying-feng;LIU Xiang-jun;WEN Ze-jun
    2008, 30(3):  58-61.  DOI: 10.3863/j.issn.1000-2634.2008.03.015
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    Well logging in cased well is important in the development of current logging technology.The casing diameter and quality of cementation and the thickness of the cement ring are the main factors which influence neutron logging.It is showed by logging data that the effectiveness of corresponding neutron logging is good,it can not only indicate the relative variety of the hydrogenbearing quantity of layers but also be used in identifying reservoir.The emendation of 17.78cm and 24.45cm neutron logging can be processed by the way of plate emendation,oneparameter regression analytical method,multiparameters step regression method and the BP neutron network method,it is proved by real information processing that the BP neutron network emendation method has the highest precision,while other ones the approximate precision.The information got by 17.78cm neutron logging and its emendation effectiveness is better than that 24.45cm neutron logging.According to the real logging information,The corresponding emendation as followed is recommended,if there are well diameter and long and short space neutron counting rate,BP neural network method is used to correct neutron logging data of cased well,and when well diameter is not available,oneparameter regression analytical method is appropriate.
    PREDICTION OF FORMATION PARAMETER PROFILE WITH CONTINUOUSLY PROCESSING LOGGING DATA
    GAO Chengjun;CHEN Haiyun;LU Qinglan;JIANG Tao;WANG Yanjun
    2008, 30(3):  62-64.  DOI: 10.3863/j.issn.1000-2634.2008.03.016
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    Many formation parameters in the drilling section,including the physical and chemical parameters,mechanics parameters and rock drillability parameters are playing an important role in instructing drilling engineering.A simple and useful method which is easy to carry out the computing is given.The method uses the discontinuity and different interval parameters that are the physical and chemical parameters,mechanics parameters and rock drillability parameters which come from rock experiment,by means of the integrated prediction technology which is based on the traditional statistic theory and burgeoning grey theory,and then,the logging information of the whole well is combined and the above parameters of the whole well section synthesized.
    HIGH FIDELITY PROCESSING FLOW OF 3D SEISMIC DATA
    TU Zhi-hui;LI Nan
    2008, 30(3):  65-67.  DOI: 10.3863/j.issn.1000-2634.2008.03.017
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    Aimed at the increasing complexity of seismic survey targets,the targets getting smaller,more types and hard to figure out,the better accuracy is acquired in seismic survey.It is well known that 3D seismic survey can provide more plump and fined underground information than 2D survey does,and it can meet the needs of accurate processing and reservoir prediction.Through the study on the reasonableness of seismic data processing flow,it is recognized that in order to ensure the quality of data processing,what should be done the first is to arrange a good processing flow of targets according to original data.The research achievement of processing flow of 3D seismic data high fidelity is applied to the pilot test of 3D seismic data modules in Chongxi,Sichuan Basin,a set of processing scheme of 3D high fidelity suitable for the studied area is presented.
    THE APPLICATION OF GEOGRAPHIC INFORMATION SYSTEM IN GEOLOGY
    ZHAO Yong-jun;FU Xiao-ning;YANG Wen-wen
    2008, 30(3):  68-71.  DOI: 10.3863/j.issn.1000-2634.2008.03.018
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    Geographic Information System (GIS) results from the development of information technology and information industry,and is a science and technology that develops rapidly in recent years.It has been used in the whole field with respect to spatial information.With the development of the information technology,GIS will gradually trend to WebGIS,ComGIS,OpenGIS,Temporal GIS,Virtual GIS,3D GIS and 3S Integration.In geology field,GIS is broadly used in some fields such as mapplotting,geological disasterforecasting,management of petroleum exploring data and forecasting and assessment of mineral resources and so on.The development of GIS technology makes the application of GIS in geology further and broader,but because of the indelibility of expert knowledge,the expert system need to be considered on the basis of GIS development,which is the development direction of geology field.
    石油与天然气工程
    THE INFLUENCE OF WELL COMPLETION WAY ON PRODUCTIVITY OF REASONABLE SAND PRODUCTION WELL
    SHAN Gao-jun;DU Zhi-min
    2008, 30(3):  72-75.  DOI: 10.3863/j.issn.1000-2634.2008.03.019
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    In order to perfect the nearly presented partial technology in new mode of effective development of offshore heavy oil field,that is the drilling and production support technological system which takes drilling fracturing well,limited sand production and electric submersible progressive cavity pump as main technologies,according to the skin factor model and productivity model of drilling fracturing well with different completion ways including barefoot completion,perforation completion and screen pipe completion etc,the influence of different technology parameters of different completion ways on reasonable sand production well is researched.The result indicate these parameters impact the physical property of sand production belt and thereby the oil well productivity to some extent.It is necessary to strictly estimate the influence of completion ways and its technological parameters on the physical property of sand production belt and thereby on the oil well productivity.
    THE DAMAGE MECHANISMS AND PROTECTION TECHNOLOGIES OF GRANITE RESERVOIRS
    ZHAO Feng;TANG Hong-ming;MENG Ying-feng;LI Gao;WANG Zi-li
    2008, 30(3):  76-80.  DOI: 10.3863/j.issn.1000-2634.2008.03.020
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    There are some differences in characteristics of lithology,physical property,pore texture and sensitive minerals between granite reservoir and conventional reservoir,so the damage mechanisms of the granite reservoir are different from conventional reservoir.By utilizing such research methods as Scanning Electron Microscope,Cast Thin Section etc,the damage mechanisms of granite reservoirs are systematically analyzed,and the effective protection measures of granite reservoirs are explored.The study results indicate that the main damage mechanisms of granite reservoirs are solid invasion,stress sensitivity and water blocking;in"five types of sensitivity"damage,acid sensitivity and salt sensitivity are main damage types,the other sensitive damage are relatively weak.Combining the literature investigation with damage mechanisms study results,the underbalanced drilling technology is believed to be the best choice to exploit granite reservoirs,if the underbalanced drilling technology is integrated with nonstraight well technology,the multiple fractures in granite reservoirs can be crossed,so the better productivity can be achieved.Low pressure bridge plug technology can not plug the macroscopic fractures and big size fractures,but the fractures those width is less than 50 microns can be effectively plugged and the part of productivity is protected.
    EXPERIMENTAL STUDY ON PHASE BEHAVIOR OF GAS CONDENSATE RESERVOIR OF FENGSHEN WELL1
    ZHOU Lun-xian;CHU Xiao-bing
    2008, 30(3):  81-84.  DOI: 10.3863/j.issn.1000-2634.2008.03.021
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    Fengshen well1 gas condensate reservoir is the first discovery of Paleogene deep gas condensate reservoir in Jiyang Depression.The authors of this paper study in detail on the phase behavior of gas condensate reservoir of Fengshen well1 based on the analysis of formation fluid composition,experiment of constant composition expansion and constant volume depletion,along with continuous measurement of downhole temperature and pressure.The results suggest that the reservoir of Fengshen well1 belongs to unsaturated gas condensate one with high temperature and high pressure,but without oil ring.The content of intermediate and heavy hydrocarbon composition is high.The content of oil is 606g/cm3,which shows that the gas condensate reservoir is rich of condensate oil.The difference between formation pressure and dew point pressure is 6.70MPa,and with natural depletion drive,the formation pressure drops sharply.When producing with 6mm flow nipple,formation pressure near well bore decreases below dew point pressure in the early production period,the retrograde condensate phenomenon occurs.Due to the serious loss of retrograde condensation,low recovery of heavy hydrocarbon component and the increase of filtrational resistance caused by oil/gas twophase flow,the production of individual well decreases.Study on the phase behavior provides the basis for reserve evaluation of hydrocarbonbearing glutenite and profiling of development program,and can guide significantly the exploration and development of the same types of reservoirs in Jiyang Depression.
    PRACTICE OF EOR DURING THE ULTRAHIGH WATER CUT PERIOD IN SHUANGHE Ⅴ FORMATION
    XU Xue-pin;LI Zhi-ping;LI Xi-yu
    2008, 30(3):  85-88.  DOI: 10.3863/j.issn.1000-2634.2008.03.022
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    Ⅴ formation in Shuanghe oil field has already entered the late period of ultrahigh water cut,with water cut of up to 95.21%.Because of innerlayer and interlayer heterogeneity of reservoir,between layers there is big difference in production,and the main pay zones are severely flooded.In this paper,the main developing problems in V formation are analyzed,the distance between oil well and water well is big,wellpattern is not perfected,injected water is insufficiently used and injected water absorption profile is asymmetry.Distribution of the remaining oil is established according to oilwater well test and reservoir numerical simulation data.This research indicates that next adjustment direction is remaining oil accumulation area located in the side of formation,adjacent faults and the high remaining reserve regions.Some EOR technologies are put forward,including adjusting and perfecting wellpattern,blocking the larger reservoir pore space in order to adjust profile control,and developing tertiary recovery.After these technologies are used in practice,obvious effectiveness of increasing oil and decreasing water production is achieved,and the water flooding recovery is enhanced.A set of enhanced oil recovery technologies is formed,and it provides a referential evidence for improvement of development effectiveness in the period of ultrahigh water cut.
    WATERFLOODING FEATURE AND REMAINING OIL DISTRIBUTION IN THE PROCESS OF HEAVY OIL EXPLOITATION
    XU Hui-yong;TAN Qing-song
    2008, 30(3):  89-93.  DOI: 10.3863/j.issn.1000-2634.2008.03.023
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    Huan127 oilfield has been in extra high water cut period,but even there is high potential of remaining oil.For the complex water flooding feature,the water intrusion and water influx rate are tested,and the water flooding feature analyzed.It is concluded that the main reason is bottom water coning,then is underscreen water channeling and fault water flooding.Water flooding extent is different in different part of the area.Edge water does not result in water flooding.Based on study of water flooding features,according to dynamic test and numerical simulation,remaining oil distribution of this block is studied in detail.Remaining oil is mainly separated in these areas,i.e.,big effective thickness and high initial reserves area;relative high effective thickness but less explorative well area,reservoir peripheral and some less production efficiency area.The research above can provide geologic basis for oilfield adjustment and potential tapping.
    EXPLOITATIVE LAW RESEARCH ON HEAVY OIL RESERVOIR WITH EDGE AND BOTTOM WATER
    LI Kui-ying;CHEN Hui;YANG Dong-ming;ZHU An-chang;YANG Yu-ling
    2008, 30(3):  93-96.  DOI: 10.3863/j.issn.1000-2634.2008.03.024
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    There are abundant heavy oil reservoirs in Shengli oilfield,but most of them with active edge and bottom water.During the process of huff and puff,the reservoir pressure decreases continuously,which results in the edge and bottom water advancing forward,water content ratio of flooded area raises sharply,and water flooded area expands which comes up to 70 percent of the total producing area.In order to enhance the ultimate recovery factor,exploitative law is analyzed in heavy oil reservoir with edge and bottom water.Displacement performance curve is applied in heavy oil reservoir for the first time.And in accordance with the present situation of water invasion,the whole heavy oil reservoir is divided into different well blocks,i.e.,strong watercut block,weak watercut block,nonwatercut block,and outer layer watercut block etc.Variation law of development target is analyzed by using heavy oil permeability knowledge.According to different development contractions,distinct adjusting program is adopted,and then remarkable effect is acquired
    APPLICATION OF MOVEABLE GEL DISPLACEMENT ADJUSTMENT IN CONVENTIONAL HEAVY OIL RESERVOIRS
    DU Yu-hong;WU Xing-cai;CHEN Hong;ZENG Qing-qiao
    2008, 30(3):  97-101.  DOI: 10.3863/j.issn.1000-2634.2008.03.025
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    Moveable gel (MG) displacement adjustment is a developing IOR/EOR new technology.It is also called improved polymer flooding or technical upgrading of polymer flooding.In this paper,the research and application of moveable gel displacement adjustment technology for Menggulin conventional heavy reservoirs from laboratory to field is introduced.It is indicated that MG displacement adjustment is of the advantages of both deep profile control and polymer flooding,and can effectively"plug"large pore channels,improve mobility ratio and solve the problems on both vertical and horizontal directions.As a kind of displacement mode,MG displacement adjustment can effectively solve water flood development problem of common heterogeneous heavy oil reservoir occurring at late stage of development.Since the beginning pilot test 5 years,the accumulative incremental oil has been 5.88×104t.The test has achieved good technical and economic effect.
    THE EFFECTIVENESS OF DEVELOPING COMPLEX SMALL FAULT BLOCK OIL RESERVOIR WITH HORIZONTAL WELL PATTERN
    XIE Xiao-qing;DING Mei-ai;JIANG Han-qiao;CHEN Min-feng;Luo Cong-yong
    2008, 30(3):  102-105.  DOI: 10.3863/j.issn.1000-2634.2008.03.026
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    The unique feature of complex small fault block oil reservoir is complex geological structure,complex fluid property and complex oilwater system and so on.By analyzing and researching the relationship between the angles of horizontal well and vertical well,permeability,net thickness,the length of horizontal hole section,oil/water viscosity ratio,vertical well completion section and injector and producer distance,development methods of two kind of horizontal well pattern are researched and reasonable pattern is determined.The result indicates that,with the increase of permeability and the length of horizontal hole section,the decrease of oil/water viscosity ratio,the degree of reserve recovery continuously raises.The influence of effective thickness on the degree of reserve recovery is not severe.And horizontal well and vertical well pattern can exert the double advantage of horizontal wells and vertical wells more fully and enhance oil recovery greatly.
    THE GASWELL PRODUCTIVITY DECLINE RESEARCH BY MEANS OF NUMERICAL SIMULTION
    LIANG Bin;Zhang Lie-hui;LI Min;WEI Na;XU Jia-nian
    2008, 30(3):  106-109.  DOI: 10.3863/j.issn.1000-2634.2008.03.027
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    With the help of the singlewell numerical simulator of the numerical simulation software,the single gaswell models of productivity decline for both abnormal and normal pressure gas wells are established,and the gaswell productivity decline data for both abnormal and normal pressure gas wells are obtained.Based on these productivity data and combined with two kinds of automatic matching model,the decline parameters,kgh,kg/Φ,and OGIP for both abnormal and normal pressure gas wells can be determined.Meanwhile,in this article,a way of acquiring the formation parameters by firstly removing the unsteady productivity data and then by following the automatic matching model is adopted,which can improve the predication precision,and the calculation results are justified with the touchstones of these two models respectively.The calculation results show that the two models are in good agreement with those of numerical simulation.
    油气化学工程与化工
    THE EXPERIMENT STUDY OF ASS－1 DRILLING AND COMPLETION FLUID SYSTEM OF BRIDGE PLUG IN LABORATORY
    CHEN Zai-jun;JIN Xiang-zhe;YANG Bin
    2008, 30(3):  110-112.  DOI: 10.3863/j.issn.1000-2634.2008.03.028
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    According to practical drilling on site,in laboratory the average recovery rate of core permeability can be up to 89% and its recovery rate is improved to 93% after nitrogen penetrates adversely the core damaged statically and dynamically by ASS-1 drilling fluid system.The pressure less than 1.0MPa at which the mud cake lifts off shows that the temporary plugging is cleaned up easily by pressure on oil formation or gas formation without other methods.It also demonstrates that the size of temporary plugging particle conforms with the size of capillary in formation and soft material content with plugging agent or chemical in formation makes the damage to formation of ASS-1 system very light.After the section of the core long about 1cm is cut off from damaged end,the permeability increases sharply,up to average 137% and which shows that the depth of damage is less 1cm.At last,it is found that there is no immerging particle in the lacuna of core and ASS-1 drilling fluid system only plugs the lacuna at the surface of cores by scan electronic microscope (SEM).The studies above suggests that the choice of carbonate calcium as temporary plugging Particle is reasonable and effective and the plugging on formation happens only on the wall of well to protect formation from damage in the course of drilling and the using area of drilling and the using area of ASS-1 drilling fluid system can be extended to the field of drilling.
    SiO2 NANOLAYERS AND CHARACTERISTICS COATED ON THE SURFACE OF TiO2 PARTICLES
    HE Wen-sena;ZHU Jia-linb;LUO Hao-wena
    2008, 30(3):  113-115.  DOI: 10.3863/j.issn.1000-2634.2008.03.029
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    As an important catalyst,TiO2 is widely applied in petrochemical industry,especially,in coalbased synthesized oil and superdeep desulphure,meanwhile,TiO2 is also important raw material of white pigment.In order to improve the application function of TiO2,surfacecoating modification of SiO2 nanolayers is done to TiO2 particles.The continuous method precisely controlling PH value is used to coat SiO2 nanolayers on the surface of TiO2 particles,and TEM,HRTEM,EDS,XPS,ICP and optical property are characterized.It is proved that a continuous SiO2 nanolayer forms on the surface of TiO2 particle with thickness of some 3.5~4.0nm,the SiO2 gel nanolayer is quite tight without floccus on noncoated film,and the TiO2 is dispersed in the shape of single particle,there is no the occurance particles being coated together.XPS indicates SiO2 gel on the surface of TiO2 particle after coating is physically coated.After coating,the optical property of SiO2 sample is apparently improved,and the dispersing property of the sample in different media is changed,in water,the dispersing ability increases to 93.6%.The surface treatment,as a catalyst,can be used in coalbased synthesized oil and superdeep de sulphure
    ENHANCING EARLY STRENGTH OF THE LOWDENSITY FLYASH CEMENT SLURRY SYSTEM
    YANG Zhenkea;GUO Xiao-yang;LI Zao-yuan;DING Yu-jieb
    2008, 30(3):  116-118.  DOI: 10.3863/j.issn.1000-2634.2008.03.030
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    In order to meet the needs of the development of the cementing,aiming at the problem of early strength of the lowdensity flyash cement slurry,authors of the paper analyze and discuss the action mechanism in the course of hydrating reaction of fly ash in low density composite material cement.A new kind of highly efficient early strengthening agent DY is developed,and this production is efficient for early strength of fly ash in the low temperature environment.Increased early strength of light weight fly ash cement slurry in low temperature is principally based on interaction between cement and fly ash.The authors analyze both the positive and negative experimental results.The results indicate the development of pozzolanic reaction and stone strength of fly ash is based that Ca2+ and OH- which is hydration product composition of well cement released to slurry as many as possible.This study is useful for cementing in the long isolation section of large borehole and lost circulation and blowout environment.
    OPTIMIZATION AND APPLICATION OF DRY METHOD DESULFURIZER IN UNDERGROUND NATURAL GAS STORAGE
    WANG Jing-bo
    2008, 30(3):  119-122.  DOI: 10.3863/j.issn.1000-2634.2008.03.031
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    The characteristics of ferric oxide desulphurizer and active carbon desulphurizer and effects of various processing parameters on break through sulfur capacity are studied through experiment.The two kinds of desulphurizers are compared based on the experimental data.Experimental results indicate that EF-2 of ferric oxide desulphurizer and 3018 of carbon desulphurizer are better.3018 carbon desulphurizer is of better desulfurizing efficiency and safety,it is more suitable to be applied in field.Influencing factors of 3018 dipping modified active carbon desulphurizer is studied and was applied in Lamadian underground natural gas storage,Daqing Oilfield.The application shows that 3018 modified active carbon desulphurizer can clean content of H2S below national standard.
    EXPERIMENTAL STUDY ON DEAROMATIZATION OF KEROSENE BY COMPLEXATION ADSORPTION
    CUI Ying-xian ;TANG Xiao-dong;;WANG Huan-mei ;HU Xing-qi;;ZHOU Dan
    2008, 30(3):  123-126.  DOI: 10.3863/j.issn.1000-2634.2008.03.032
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    Considering such problems as high energy,environment pollution and low dearomatization efficiency of traditional dearomatization technology,a new complexation adsorption dearomazitation technique is proposed.Dearomazitation of kerosene is studied by using AlCl3－HCl complexant.Experimental results show that arene content in clear kerosene can be lowed to 0.68% with dearomatization efficiency of 91.1% under certain conditions,i.e.,AlCl3 dosage 0.80mol/L,HCl dosage 1.05mol/L,complexation adsorption temperature 60℃ and adsorption time 25min.The complex compound may be further decomplexed so as to reclaim the arene of raw kerosene.
    PROGRESS IN POLYMER/SURFACTANT BINARY COMBINATION DRIVE
    LV Xin;ZHANG Jian;JIANG Wei
    2008, 30(3):  127-130.  DOI: 10.3863/j.issn.1000-2634.2008.03.033
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    Aimed at the presentation and characteristics of polymer-surfactant binary system,indoor research situation of polymer-surfactant binary system and the test in the seventh block 54-61 of Gudong,Shengli oilfield are summarized.The polymersurfactant binary combination drive is a low concentration one formed on the basis of dealkali ternary system,which can greatly enhance the viscosity and elastic of polymer,minimize the negative effect induced by emulsion treatment,totally wipe out scaling of formation and well bore due to the existence of alkali.By researching home and abroad literatures,it is suggested that the polymersurfactant binary system can increase recovery by 20%,good result is achieved in field test.The system can overcome the weak point of ternary system,there is a bright prospective as a new oildisplacing method.
    HUMIC ACID PLUG AGENT USED IN HIGHTEMPERATURE AND LOW PERMEABLE RESERVOIRS
    GAO Zi-donga;LI Jingb;HE Xiao-Juanb;WANG Bob;SUN Hua-lingb
    2008, 30(3):  131-135.  DOI: 10.3863/j.issn.1000-2634.2008.03.034
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    A new plug agent which is made mainly from humic acid,formaldehyde,strength agent and 0.02% HPAM solution is studied.The influences of concentration of humic acid,cross linking agent,temperature,pH value and salinity on the property of the agent are studied,too.Orthogonal test is conducted to optimize the formulation and evaluation.The result indicates that its initial velocity is 10mPa·s,which can easily reach deep formation.The gelation time is 18h and gelation strength 0.087MPa.The excellent application range of pH value is 7~9.The properties include temperatureresistance and antisalt,long term stability,good plugging ability and low cost,it is very suitable for high temperature and low permeable reservoirs.
    石油机械工程及其它
    THE FAILURE ANALYSIS OF THREE ROLLER BIT SLIDING BEARING
    HUANG Zhi-qiang;WANG Xiao-feng;Tu Xiao-Fang;Li Qin;Tan Li
    2008, 30(3):  136-138.  DOI: 10.3863/j.issn.1000-2634.2008.03.035
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    The life of drilling bit is directly determined by three roller bit bearing′s service life.In order to find out failure form,the failure causes and mechanism of three roller bit,and further improve the life of three roller bit,Macroscopic and microscopic analysis of failed three roller bit bearing are done in this article.The results show that failure of sealing system is one of the main reasons of the failure.Overload and unbalanced distributing loads and high temperature deteriorates wear resistance and strength of metal,big radial clearance between bearing and cutter,vibration in rotating are also the primary reason of three roller bit bearing failure.
    CASING COLLAPSE RESISTANCE ANALYSIS AND CALCULATION
    SHEN Zhao-xi;FENG Yao-rong;XIE Xue-dong;YANG Peng
    2008, 30(3):  139-142.  DOI: 10.3863/j.issn.1000-2634.2008.03.036
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    To improve the precision of casing collapse pressure calculation,the variance analysis of the full scale collapse test data of 213 casings is conducted with statistical method.The effects of outer diameter/wall thickness,material yield strength,ovality,eccentricity and residual stress on the casing collapse resistance are analyzed in this paper.The results show the ratio of diameter and thickness and yield strength are the main parameters of influencing the collapse pressure of casing,and the decreasing of the casing collapse resistance is a random process with the increasing of ovality,eccentricity and residual stress.And the casing simulation analysis of various combinations of the location of ovality,eccentricity and residual stress under external pressure is performed.From the simulation results,it is concluded that the casing collapse pressures differs greatly between different combinations.In the end,a new casing collapse calculating formula is put forward which gives the more accurate prediction of casing collapse,the accuracy can meet the requirement of application.
    PIPELINE DESIGN CRITERIA BASED ON STRAIN AND THE CONTROL FACTORS
    LIU Bing;;LIU Xue-jie;ZHANG Hong;
    2008, 30(3):  143-147.  DOI: 10.3863/j.issn.1000-2634.2008.03.037
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    Traditional pipeline design analysis method presented in various literatures is usually based on limit stress criteria,however,the method may be inapposite to modern steels,and the method can not solve all the problems in pipeline strength design,especially for displacement controlled loads such as ground displacement load.Strain limits,including ovalization limit,tensile strain limit and compressive strain limit,are compared in this paper based upon various codes and recommendations.In addition,some control factors of strain limits are also reviewed respectively.In view of the design tendency based on strain and the largescaled construction of gas transportation from west to east,as well as the second level projects,the importance and necessity of the related research are presented.
    NUMERICAL SIMULATION AND OPTIMIZATION STUDY ON OILWATER SEPARATION HYDROCYCLONE
    NIU Gui-feng;AI Zhi-jiu;LIU Chun-quan;HE Hui-qun
    2008, 30(3):  148-151.  DOI: 10.3863/j.issn.1000-2634.2008.03.038
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    The flow field of oilwater two phases in oilwater separation hydrocyclone is tested by means of Reynolds streess model and CFD numerical simulation method.The consequence suggests the interflow disturbance of produced liquid on inlet exerts an important influence on oilwater separation effect,so,a new structure,spatial Archimedes spiral line inlet flow channel and the conduction current spiral oilwater separation hydrocyclone,is presented.The further optimal design and function test indicate smooth transition between Archimedes spiral and cyclone inlet is realized,and the stable flow field and higher separation efficiency are obtained.
    NEW TECHNOLOGY STUDY ON PETROLEUM GRID DATA MINING
    XIAO Ji-yia;HU Ronga;WANG Yi-qunb
    2008, 30(3):  152-154.  DOI: 10.3863/j.issn.1000-2634.2008.03.039
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    In petroleum exploration and production areas,massive data collections of terabyte(TB)and petabyte（PB）scale need to be used and analyzed,moreover,in many cases,these data sets should be shared by large communities of users that pool their resources from different sites of a single organization or from a large number of institutions.Grid will become the information infrastructure of business workflow in the petroleum industry.Advances in grid computing technology will meet the tremendous and scalable demands of petroleum exploration and production for high performance computing.Grid platform can provide a lot of useful services when people process data sets,task management,for example,resource management and scheduling are some of these services.To show the benefits of the grid environment,the grid data mining integration technology and the grid data mining ontology technology are presented.Integrating Web service and grid technology,grid and data integration technology and composing ontology and Web service are presented,too.This performance is implemented on top of the Globus Toolkit 4,the open grid services architecture and Web service.
    CITY GAS STATION MARKETING PERFORMANCE EVALUATION BASED ON THE BEHAVIOR
    LIU Hong-yuan;;YU Xiao-zhong;SHI Shi-xin;YAN Jun-mei
    2008, 30(3):  155-158.  DOI: 10.3863/j.issn.1000-2634.2008.03.040
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    In the competitive market model,the performance of city gas station is created by the acts of sales,while the sales are generated by the behavior of consumer awareness,consumer behavior,the competitive environment,marketing innovation and other elements of composition,performed by the sales marketing common elements of the result.Based on this understanding,such factors as sales of consumer awareness,buying behavior,market structure,innovation constitute the overall index,and according to intron system,the main indicators of the indicators are decomposed,the city gas stations Marketing Performance Evaluation System is constructed,in accordance with the index system level nature,by using hierarchical analysis methods and selection of specific stations,the construction of the index system is tested.The results show that consumer satisfaction,loyalty and recognition of the quality of service performance of gas stations have an important impact on marketing.
    基础理论
    RESEARCH AND APPLICATIONG OF MONTHLY NATURAL DECLINE RATE PERDICTION
    XIAO Wu;ZHANG Xiao-tian;DING Li
    2008, 30(3):  159-162.  DOI: 10.3863/j.issn.1000-2634.2008.03.041
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    Natural decline rate is an important index of yield variation of oil field.In view of the predicting circumstance by experience in the past,formula of monthly natural decline rate is deduced in the regular pattern of exponential decline,double curves decline and harmonic decline.On this basis,empirical formula prediction of monthly natural decline rate is proposed on the basis of considerable research and analysis of real field data.According to this method,monthly natural decline rate can be predicted easily and promptly so as to set monthly output performance and workload arrangement of yearly deployment appropriately.It also can be an important reference to early warning for dynamic tendency of development.It can guide the management of the oil field development and production.
    博导论评
    DYNAMIC ANALYSIS OF BOREHOLE WALL STABILITY IN THE DRILLING PROCESS
    LIAN Zhang-hua;LIU Xin;FANG Hao;YANG Bin;XIAO Zhou
    2008, 30(3):  163-166.  DOI: 10.3863/j.issn.1000-2634.2008.03.042
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    Most of the Borehole stability investigations in existence are static,which approximate rock to invariant mechanical isotropic body.So the conclusion may deviate with the real situation during the dynamic drilling process.With the formula based on the Mohr-Coulomb strength criterion,applicable safe density window of drilling fluid is calculated in this paper then,with the Lifeanddeath element method,drilling process and buildup of the mud cake and contaminated zone are simulated.Integrating the conclusion of simulation with the theoretic safe density window of drilling fluid,the dynamic alternating regulation of borehole wall stress during the drilling process is investigated.
    探讨与争鸣
    THERE IS NOT A STARTING PRESSURE GRADIENT IN LOWPERMEABILITY RESERVOIRS AT ALL
    LI Chuanliang;YANG Yongquan
    2008, 30(3):  167-170.  DOI: 10.3863/j.issn.1000-2634.2008.03.043
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    There are many misunderstandings of lowpermeability reservoirs,one of which is the starting pressure gradient for fluids to flow through.Pores are underdeveloped in lowpermeability reservoirs,so permeability and productivity of lowpermeability reservoirs are quite low,and pressure transits at quite low speed.While a pressure gradient is established in lowpermeability reservoirs,the response of production needs a long time period.The weak flow rate from experiment in laboratory is misunderstood as zero,which results in the socalled"starting pressure gradient"phenomenon.The measured starting pressure gradients are usually too high to instruct the oil/gas production of lowpermeability reservoirs.There are not starting pressure gradients for midand highpermeability reservoirs,so not for lowpermeability reservoirs.There are not yielding shearing stresses for solids and liquids,so not for oil and gas.