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    20 April 2007, Volume 29 Issue 1
    专家论坛
    Discovery of Oolitic Shoal Reservoirs in Feixianguan Formation and the Characteristics at Northwest Sichuan
    SHEN Ping ZHAO Zuo-an ZENG Yun-xian YANG Yu
    2007, 29(1):  1-4.  DOI: 10.3863/j.issn.1000-2634.2007.01.001
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    The authors summarized the process and history that natural gas was obtained by drilling in well Ba 3 in Fei 1 member at Shiyougou, east Sichuan in 1963, and then Feixianguan Formation gas reservoirs were discovered in Fuchengzhai, Bandong and Huangcaoxia structure successively, in well Du 1 at Dukouhe structure, poroustype dolomite was found and natural gas current was gained, a number of whole package oolitic shoal gas reservoirs in Feixianguan Formation at Luojiazhai, Tieshanpo and Jinzhuping were explored. Based on the exploration data, source rocks, reservoirs, cap condition of the reservoirs in northeast Sichuan are analyzed, meanwhile, it indicates that crude cracked gas is dominated in Feixianguan Formation gas and source rocks in Permian. The types of reservoir rocks mainly are oolite dolomite and dissolved porous oolite limestone. Through the formation evaluation, the favorite area of reservoir development can be predicted. By analysis of the process of gas reservoir forming, it is considered the process is classified into three phases: paleooil reservoir, large scale reservoir and paleo gas reservoir reforming. Finally, based on geologic structure, sedimentary facies distribution and trap factors, the forming mechanism and the reservoir characteristics in Feixianguan Formation oolitic shoal reservoirs in Luojiazhai structure are analyzed.
    地质勘探
    THE MOUNTAINOUS WIDE AZIMUTH 3D PROSPECTING TECHNOLOGY & THE APPLICATION EFFECT IN LUOJIAZHAI AREA
    XIE Fang ZHU Min HUANG Hua-xiang MEI Yan
    2007, 29(1):  5-9.  DOI: 10.3863/j.issn.1000-2634.2007.01.002
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    Abstract: 〖WT5BZ〗The Luojiazhai area in northeast Sichuan Basin is dominated by the geologic bodies with high mountains, highsteep complex structures and anisotropic geologic medium, where 2D and 3D narrow azimuth prospecting would not meet the seismic requirements, the fine interpretation is needed urgently. Through research for years,and the analysis of the characteristic and difficulty of wide azimuth 3D prospecting in high mountains, a set of seismic technique, i.e, mountainous wide azimuth 3D acquirement technique, with observing system of midpoint shot, 8×5 folds, line distance 400m, mini shotreceiver distance 565.7m, max shotreceiver distance 4216m, wide azimuth 3D processing technique with 3D floating datum plane, tomography static rectification, series migration in the velocity field, 3D interpreting technique based on wave equation forward, multiwell restrict backward, poststack fissure detection for seismic attribute and wide azimuth 3D reservoir predication technique, has been integrated and applied with the satisfied results obtained in Luojiazhai area in northeast Sichuan.
    RESEARCH ON SEDIMENTARY PALAEOTOPOGRAPHY OF EARLY FEIXIANGUAN PERIOD AT SOUTHWEST LUOJIAZHAI AREA
    ZENG Yun-xian LIU Wei YANG Yu
    2007, 29(1):  10-11.  DOI: 10.3863/j.issn.1000-2634.2007.01.003
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    Research on sedimentary palaeotopography at southwest Luojiazhai area is operated with logging Gama data. It is indicated, on the basis of the comparison with logging curve of almost 100 wells, that the electric property change at lower Feixianguan formation is concentrated at the 50m range from the bottom. Research on sedimentary palaeotopography of early Feixianguan period is conducted with Gama average data of 50m section from bottom of the formation, it is indicated that Gama data range(20~30API)would be favorable for oolitic development, and meanwhile it is also the favorable areas of late oolitic dolomite and oolitic reservoir development, according to favorable facies, high palaeotopography, dolomization at adjacent wells and good quality of reservoir development, the two favorable exploration blocks, QL25PX1 area and DT 7DT 5 are figured out.
    RESERVOIR LOGGING EVALUATION OF FEIXIANGUAN FORMATION IN LUOJIAZHAI GAS FIELD
    LUO Ning YU Guang-yi ZHAO Zuo-an
    2007, 29(1):  12-14.  DOI: 10.3863/j.issn.1000-2634.2007.01.004
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    Luojiazhai gas field is composed of Luojiazhai structure and Gunziping structure, and is the most important gas field in northeast Sichuan. Feixianguan Formation reservoir in Triassic is the best carboniferous successor in Sichuan basin. On the initial exploration, a lot of excellent image logging data and regular logging data are obtained. The following conclusions are obtained based on analysis of the criteria for the classification of the reservoir, fluid properties of discrimination and single well productivity forecast, i.e, Feixianguan Formation reservoirs are dolomite Karst pores and caves oolitic shoal reservoirs, reservoir spaces include a variety of pores, caves and fractures. Luojiazhai structure is porous reservoir and Gunziping structure is fracturedporous reservoir. All abovementioned provide the basis for further development.
    石油与天然气工程
    THE SIGNIFICANCE OF DISSOLUTION IN THE DEVELOPMENT ANDEVOLUTION OF RESERVOIR IN FEIXIANGUAN ORMATION IN THE NORTHEAST SICHUAN BASIN
    ZENG De-ming WANG Xing-zhi WANG Si-yi
    2007, 29(1):  15-18.  DOI: 10.3863/j.issn.1000-2634.2007.01.005
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    There are not only wide distribution, great thickness and various types of Marine carbonate rocks of Lower Triassic in Feixianguan Formation in the northeast Sichuan basin, but also many periods of evolution which involve the diagenesis and tectonism, the rocks have evolved into bank facies dolomite reservoir with excellent reservoir property. Based on the study of the sedimentaiotn, diagenesis, tectonic burial history and the heat evolution of organic matter, the authors research the dissolution which is very important to the development and evolution of reservoirs in Feixianguan Formation in the northeast Sichuan. According to the dissolution characteristics and geochemical characteristics of chemical fillers, four stages of dissolution are identified, they are quasisyngenesis stage, liquid hydrocarbon stage, gaseous hydrocarbon stage and structure lifting stage, and then the forming mechanism of dissolution of different periods is further studied. At last, a model of the burial dissolution at liquid and gaseous hydrocarbon stage is proposed and the influence of dissolution on reservoirs concluded.

    地质勘探
    THE ORIGIN AND DISTRIBUTION OF DOLOSTONE IN FEIXIANGUAN FORMATION IN LOWER TRIASSIC SERIES, NORTHEAST SICHUAN
    ZENG Wei HUANG Xian-ping YANG Yu WANG Xing-zhi
    2007, 29(1):  19-22.  DOI: 10.3863/j.issn.1000-2634.2007.01.006
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    According to the geochemistry, sedimentology, lithology, the dolostone in Feixianguan Formation in lower Triassic series, northeast Sichuan is studied in terms of geochemistry and lithology, it is pointed out there are two kinds of dolomization in Feixianguan Formation, they are mixedwater and seepagereflux dolomitization. Oolitic dolostone formed by mixedwater dolomitization distributes along platform edge in the shape of band. Gypsiferous microcrystal dolostone and dolarenite formed by seepagereflux dolomitization distributes planarly in lagoon. Distribution research of dolomitization is made, and next exploration target is pointed out.

    INTERPRET THE LAW OF EFFECTIVE FRACTURE DEVELOPMENT BASED ON NEW TECHNOLOGY IN WELL LOGGING
    ZHANG Shu-dong SIMA Li-qiang LIU Ping-ying QI Bao-quan HE Hong-ju
    2007, 29(1):  23-25.  DOI: 10.3863/j.issn.1000-2634.2007.01.007
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    Image logging data provide the precise distribution information of fractures underground, with the data, the fracture parameters, including dip, azimuth and the combination types can be fully gained, which give valuable information for geologic analysis. the fractures in neighbor fields with similar geologic feature can be predicted based on multi well image logging data combining core data. At last, 3 effective fracture developing zones, 5 poor developing fracture zones and 2 nonfracture zones in lower Triassic Feixianguan Formation reservoir in Sichuan basin have been interpreted by studying the fracture distribution and fracture effect factors which are lithologic characters, fracture dissolution & infilling, and the relationship of fracture with present terrestrial stress and structure with 10 wells image logging data and core data. The result is confirmed by well drilling and the interpretation with the new technology is feasible. 
    HIGH RESISTIVITY AFFECTING FACTORS OF CARBONATE RESERVOIR IN NORTHEAST SICHUAN BASIN
    QI Bao-quan ZHANG Shu-dong WANG Zhao-nian SIMA Li-qiang
    2007, 29(1):  26-29.  DOI: 10.3863/j.issn.1000-2634.2007.01.008
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    Carbonate formation is characterized by higher resistivity and bigger difference of Dual and Shallow lateral logging compared with clastic formation. There are so many factors affecting the high risistivity of carbonate formations that it is difficult to identify the reservoir and interpret the property of fluids. the factors are analyzed which affect the values and differences of dual lateral logging combining the logging date with modeling results. The factors include borehole size, fracture, lithology, fluid resistivity, invasion depth etc. At last, the affecting degree to dual lateral logging is summarized and the reason of high resistivity and big fluctuating in carbonate interpreted. The conclusion is helpful to realize the change law of dual lateral logging of carbonate better as well as analyze the reservoir in detail.
    
    PROBE OF TRANDITIONAL SEISMIC FACIES IDENTIFICATION TECHNOLOGY OF OOLITIC RESERVOIR, FEIXIANGUAN FORMATION
    LIU Wei ZENG Yun-xian YANG Yu
    2007, 29(1):  30-33.  DOI: 10.3863/j.issn.1000-2634.2007.01.009
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    The exploration practice in Sichuan Basin demonstrates that the reservoirs in Feixianguan Formation, lower Triassic are the porous bodies developed at the background of large area tight rocks, and related to beach facies, in general, there is a tendency of belt and sheetshaped distribution with strong heterogeneity partially. On the basis of comprehensive geologic research, the seismic prospecting technology of lower Triassic reservoir is summarized and improved, the available seismic data are fully employed, the traditional seismic facies identification technology used in oolitic reservoirs, Feixianguan Formation is further completed, reservoir prospecting research is conducted and a set of traditional seismic identification technology suitable for KaijiangLiangping Trough is explored.

    CHARACTERISTICS AND ORIGIN OF DOLOSTONES IN YINGSHAN FORMATION, LOWER AND MIDDLE ORDOVICIAN, NORTH OF CENTRAL TARIM BASIN
    LI Ling TAN Xiu-cheng CHEN Jing-shan ZHAO Yong-gang HE Bi-zhu
    2007, 29(1):  34-36.  DOI: 10.3863/j.issn.1000-2634.2007.01.010
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    There are large amount of dolostone and wide spread dolomization in Yingshan Formation of Lower and Middle Ordovician in North of central Tarim basin,the strata is composed of all kinds of dolostone, limy dolostone, dolomited limestone and limestone which are interbedded with different thickness and deposited on carbonate platform . The dolostone includes sparry dolostone, residualgrained dolostone, residual limy dolostone and algae dolostone. By analyzing the attitude, minerlogy and geochemistry of the dolostone, the origin of dolostone is regarded as a kind of replaced one at nearsurface in evaporated sea water which can be interpreted in such model as tidal evaporating dolomiteforming and flowingdown dolomiteforming.
    WT5HZ MEASURING METHOD AND BESIC CHARACTERISTICS OF P WAVE QUALITY FACTOR OF THE DESERT SURFACE IN XINJIANG
    WANG Ya-min XU Feng WANG Qin WEI Jian-xin
    2007, 29(1):  37-39.  DOI: 10.3863/j.issn.1000-2634.2007.01.011
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    There is not a set of mature and effective method to measure formation quality factor by far. In this paper, a set of instruments and approaches are designed to measure quality factor, which can emulate the situation measured in different buried depth and water saturation condition, and measure the quality factor of unconsolidated sands or clay. Through testing many sands′samples from the Tarim and the Zhungar basin, the stability and the reliability of the instruments and the measuring technique are identified. The research discovers that compression wave quality factor of the sands in desert surface increases as the buried depth and the compression wave velocity′s increase. When the relative water content is smaller than a certain value, the quality factor increases as the water content′s decrease. After the relative water content reaches this value, the quality factor increases as the water content′s increase, which are of importance to the study of seismic wave energy loss and seismic data processing and interpretation.
    SEDIMENTARY FEATURES AND RESERVOIRFORMING CONDITIONS OF JISHAN SAND BODY IN HUIMIN SAG
    SUN Yu ZHONG Jian-hua JIANG Zai-xing WANG Zhi-kun GAO Xiang-cheng
    2007, 29(1):  40-43.  DOI: 10.3863/j.issn.1000-2634.2007.01.012
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    The Jishan sand body is the main sand body explored in Huimin Sag, the prospect for the exploration of Jishan sand body is broad. The Jishan sand body is found to be a set of deltachannelturbidity fan sedimentary system by means of analysis of lithologic characteristics, sedimentary structural characteristics and lithologic texture characteristic. The Jishan sand body is divided into four stages vertically. Grain size of the Jishan sand body is fine, and the rock is mainly composed of finegrained sandstones and siltstones. Influenced by the sedimentation and diagenesis, reservoir properties are of the characteristics of medium porosity, low permeability, strong heterogeneities and well developed secondary pore. On the basis of recognition, reservoir forming factors of Jishan sand body are analyzed, the results show that the such reservoir forming conditions as rich oil source, good reservoir, favorable migration conditions, good assemblage of generation, reservation and capsulation and various trap types, are favorable for hydrocarbon migration and accumulation. Palaeostructurallithologic traps of Panhe anticlines in the west Jishan trough and lithologic traps of Mengsi low uplift are the targets for further exploration.
    THE MATHEMATICAL MODELING OF ABSORPTION COMPENSATION IN LOOSE MEDIUM AT SUBSURFACE
    DU Zeng-li Shi Ze-jin Xu Feng ZHU Yu-huan WANG Jian-ning
    2007, 29(1):  44-46.  DOI: 10.3863/j.issn.1000-2634.2007.01.013
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    In order to improve the resolution of seismic data efficiently, it is important to study the absorption and the compensation of seismic wave in loose medium quantitatively. The distribution law of quality factor is calculated with the spectrum ratio method according to the raw well logging data collected in Tarim basin. The mathematical modeling of seismic energy absorption attenuation compensation in loose medium is studied by the phase shift technique in fx domain based on the propagation mechanics of seismic wave in elasticviscid medium. The result shows that the absorption attenuation of energy of high frequency can only be recovered by the data processing in some given condition of surface seismic geology, the conditions of completely compensating the absorption attenuation effect is given, and theoretic numerical data is provided to the reasonable upper limit of seismic data resolution in desert area.
    HYTROCARBON EXPLORATION PROSPECT OF JURASSIC IN THE WESTERN QAIDAM BASIN
    DUAN Hong-liang ZHONG Jian-hua MA Feng ZHANG Yue-hong WEN Zhi-feng
    2007, 29(1):  47-50.  DOI: 10.3863/j.issn.1000-2634.2007.01.014
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    Based on regional geological survey, seismic data and organic geochemistry analysis, the Jurassic sedimentary characteristics and petroleum geological condition in the western Qaidam Basin are studied in this paper. It is indicated that there are two sets of strata developed in the western Qaidam Basin, one is MiddleLower Jurassic dark coal bearing formation, including Xiaomeigou formation and Dameigou formation; another one is the Upper Jurassic red clastic rock formation developed in oxidation environment without hydrocarbon generating capacity. The dark mud shale developed in MiddleLower Jurassic lacustrine facies is widely distributed in the study area with large residual thickness. About 288m and 256m thickness of source rocks are developed in the Yueyashan and the Qingshuigou regions respectively. The organic geochemistry analysis shows that the average organic carbon abundance is 1.62%. The organic matters mainly belong to typeⅡ2 and partly typeⅢ. The source rocks is reaching the peak period of oil generation and discharging and are of better hydrocarbon generation capacity. The source rocks, reservoir beds and the cap rocks match each other well, and traps develops well, it can be concluded that the Jurassic in the western Qaidam Basin possesses relatively better petroleum geological conditions and good oil and gas exploration prospect.
    APPLICATION OF MICROSCOPIC SEDIMENTARY FACIES IN ONGOING EXPLORATION IN WEICHENG OIL FIELD
    WANG Jun ZHANG Jun-feng
    2007, 29(1):  51-53.  DOI: 10.3863/j.issn.1000-2634.2007.01.015
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    Through the research on microscopic sedimentary facies in Sha member 4 in Weicheng oil field, Dongpu depression, such microscopic sedimentary facies are identified from fan delta sedimentation as channels, interchannels, sheetshaped sands and deepsemi deep lacustrine. The established chief microscopic facies well logging model is employed to identify and classify single well facies, well logging plane facies association is studied, the plane figure of microscopic sedimentary facies in Sha member 4 is plotted based on the figure of sand body distribution. The prediction to sand body distribution and microscopic sedimentatary facies indicates that there is material source at southern edge of the studied area, there probably is the favorable microscopic facies such as branched channels and interchannels at the south of Weicheng oil field, there exists favorable sandbodies. Combined with reservoir prediction result, the ongoing exploration targets are sorted out optimally, the good results are achieved in 4 planned drilled wells, which proves that there is a bright oilbearing prospective in the area.
    COMPREHENSIVE EVALUATION OF WELL LOGGING OF LIGHT SANDSTONE GAS RESERVOIR AT SHAN MEMBER 2, YULIN GAS FIELD
    WANG Jianguo;HE Shunli;LIU Hongqi;LIU Guang feng;ZENG Bo
    2007, 29(1):  54-56.  DOI: 10.3863/j.issn.1000-2634.2007.01.016
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    The reservoir at Shan member 2, Yulin gas field is typically low porosity, low permeability and tight sandstone reservoir, the types of pore spaces are dominated by intergrain pores and intercrystal pores, with a few dissolved matrix pores. Lithology is the key factor impacting pore types, pore structure, physical properties of the reservoir and gascontaining property. The relationship between porosity and permeability, the types and structure of pore spaces, reserving and productive capacity and response character of electrical property in the reservoir with same lithologic property tend to coincidence. As the change of lithologic property, the corresponding relationship among the “four characters”mentioned above changes too. On the basis of fine study of the four characters and accurate identification of lithologic property, different parameter interpretation models are set up for different lithologic properties, the comprehensive evaluation of the reservoir is finally realized. The favorable reservoir areas between wells are pointed out, which provides reference for the next ongoing exploration and exploitation.
    石油与天然气工程
    SULFUR DEPOSITION MODEL AND THE APPLICATION BASED ON SOLUBILITY EXPERIMENT
    FU Dekui;GUO Xiao;DENG Shenghui
    2007, 29(1):  57-59.  DOI: 10.3863/j.issn.1000-2634.2007.01.017
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    Some gas reservoirs with high H2S content have been found in northeast Sichuan in China, such as PuGuang gas field, Luojiazhai gas field and so on. In the course of development of the gas reservoirs with high H2S content, as formation pressure falls continually, elemental sulfur will precipitate from gas phase after running up to critical saturation state and deposit at reservoir pore space and throat, consequently resulting in formation porosity and permeability reduction; gas well production halts when it becomes severe. Gas reservoirs with high H2S content sulfur deposition prediction model is set up according to dissolution mechanism of sulfur in nature gas and material balance theory and the Luo7 well taken as an example to forecast sulfurbearing saturation in different pressure range, as well as effect of sulfur deposition on production rate. Achievements show that,when gas reservoir pressure drops down to 40 MPa ,production rate falls by 82.5%;reservoir pressure drops down to 37 MPa,gas well production will halts.

    ABNORMAL WELL HEAD PRESSURE OF HIGH PRODUCTIVITY GAS WELLS IN LUOJIAZHAI
    CHEN Wei;DUAN Yonggang;LIU Baifeng;LUO Bang lin;LIU Hua qiang
    2007, 29(1):  60-63.  DOI: 10.3863/j.issn.1000-2634.2007.01.018
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    Well head pressure of high productivity gas wells performs abnormally while testing, that is the flowing pressure “bouncing descendascenddescend”, the buildup pressure “bouncing ascenddescend”, which differs completely from the change law of bottom hole pressure. Analysis result of high productivity gas wells in Luojiazhai shows temperature effect of well bore as the key factor affecting well head pressure. The reason for abnormal well head pressure is analyzed, nonlinear profile of well temperature is calculated through Hasan & Kabir unstable well bore temperature model, the calculation of well bore fluid pressure is modified and also, forecasting method of nonlinear temperature profile is merged into testing simulator with well bore and reservoir coupling mechanism, and abnormal phenomenon of well head pressure is simulated completely. By simulating, the test points in high productivity gas well is found “abnormal”in quite large range of depth, which is helpful for recognizing to using temperature data to modify pressure, and the key is to recover the normal condition in improving explanation and analysis technique.
    A NEW APPROACH OF TRANSIENT PRODUCTIVITY FORECASTING IN LUOJIAZHAI GAS RESERVOIR
    DUAN Yong-gang CHEN Wei LI Yun HU Yong LUO Tao
    2007, 29(1):  64-67.  DOI: 10.3863/j.issn.1000-2634.2007.01.019
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    The productivity in Luojiazhai gas reservoir is analyzed and forecasted according to its reservoir characteristic, the result shows that, to single well productivity forecasting, the superiority, duration and practical application of the new approach of transient well test based on coupling gas reservoir and well bore can not only be used to forecast by directly employing transient pressure test data, also, by determining formation parameters through production dynamic data matching, meanwhile, it can be used to study the different work procedure, the way of well completion and productivity change under the condition of improving EOR. The approach provides a advanced means to oil reservoir engineering research of depletion recovery.

    THE PROBE OF DEVELOPMENT TECHNOLOGY OF THE HARD RECOVERED RESERVE, QAIDAM BASIN
    LU Ming-chun LI Yu-cheng
    2007, 29(1):  67-69.  DOI: 10.3863/j.issn.1000-2634.2007.01.020
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    Qaidam basin is characterized by abundant resource of hard recovered potrogeology reserves, the scatted and small scaled reserve, complicated geologic condition, low productivity, fast production decline, high cost of exploitation and low degree of production, brings out many problems. The authors explore the measurements, strategies and suitability for the reserve in the basin. The new techniques and technologies are studied, the techniques and technologies suitable for the reservoirs are defined, application is proved economic, practical and effective.

    WELL TEST INTERPRETATION METHOD FOR HORIZONTAL MULTILATERAL WELLS
    WANG De-shan LI Zhao-min NIE Li-xin
    2007, 29(1):  70-74.  DOI: 10.3863/j.issn.1000-2634.2007.01.021
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    Based on the basic solutions of the pressure response of point source in infinite space, pressure responses at any point in a horizontally infinite reservoir are studied. Furthermore, methods of welltest interpretation are researched in aspects of observation points, equivalent pressure point and treatment for multisolutions of pressure response. An example of horizontal multilateral well with 4 branches is given as Well SZ361CF1 in Bohai Oilfield, the authors systematically study the efficient algorithm about transient pressure response in heterogeneous reservoirs with dual porosity, the calculation of equivalent pressure points in a well hole with infinite conductivity, the welltest interpretation method with serious solvability, etc. The achievement is of great importance to EOR and stimulation measures.

    THE EVALUATION OF MULTIPHASE PHASE FLOW MODEL IN UNDERBALANCED DRILLING
    PING Li-qiu WANG Zhi-ming WEI Jian-guang
    2007, 29(1):  75-78.  DOI: 10.3863/j.issn.1000-2634.2007.01.022
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    In order to provide a practical bottom hole pressure prediction model to the engineering design of underbalanced drilling (UBD), six pressure prediction models which are established according to homogenous flow approach (Guo Boyun model),empirical correlation approach (BeggsBrill Model, Orkiszewski Model, Han HongshenCheng Jialang Model) and mechanistic approach (HasanKabir model and modified Ansari model) are used to predict pressure drop in UBD. The six algorithms are implemented into a FORTRAN 90 computer program. Gasliquid twophase flow in annuli in UBD is simulated by the six models and bottom hole pressure is predicted in gasifiedliquid UBD. The prediction results are validated with field data and fullscale experimental data. The predictions precision of the models is presented.The comparative analysis shows that modified Ansari model better pressure prediction in underbalanced drilling and it satisfies the accuracy demand of underbalanced drilling. The method is recommended in the design of underbalanced drilling to maintain full underbalanced status and economic benefit target of underbalanced drilling is obtained.

    THE WELL TEST INTERPRETATION OF PARTIALLY PERFORATED VERTICAL WELL IN THIN BED BOTTOM WATER RESERVOIR
    LI Cheng-yong LIU Qi-guo ZHANG Lie-hui ZHANG Ran ZHANG SHeng- bing
    2007, 29(1):  79-81.  DOI: 10.3863/j.issn.1000-2634.2007.01.023
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    Bottom water reservoirs are common in China, in this article, instantaneous point source diffusion equation is established for thin bed bottom water reservoir, using Lord Kelvin point source solution, principle of superposition, mirror response, the basic solution of flow through porous medial differential equation in this types of reservoirs is obtained, Poisson formula is used to simplify the expression, the theory of point source function is used to obtain bottom hole dimensionless pressure response in thin bed bottom water reservoir, the dimensionless pressure is calculated and pressure derivative dual logarithmic theory chart obtained, from this, the character of flow through porous media in vertical well in thin bed bottom water reservoirs and the influence factors are analyzed, well test interpretation software is developed.
    STRENGTH ANALYSIS OF BHA WITH ECCENTRIC SUBASSEMBLY IN DEFLECTION CONTROLLING AND DRILLING FLEETLY
    NIE Rong-guo SHI Xiao-bing LIU Peng CHEN Ping DU Qing-cai
    2007, 29(1):  82-84.  DOI: 10.3863/j.issn.1000-2634.2007.01.024
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    In terms of certain conditions, to use the assembly of bevel strings is one of the best effective fleet inclinedproof drilling techniques. The forcereceived estate of assembly of bevel strings which is applied in the technique of bevel strings fleet inclinedproof is very complex and greatly affects the security of whole drill string system. In order to realize a safe, effective drilling operation, to analyze the strength of bevel joint and its neighboring drill collars is very necessary. At the same time, it′s very important to find out the danger point of assembly, and it′s very expediently to proofread the strength of drilling strings and improve its structural design. Some research indicates that the most compound stress of bevel inclinedproof strings is commonly situated in the bonding site of bevel joint and underneath drill collar which is derived from the bend load and axial force. In the most dangerous place, the security of drilling tool′s strength should be concerned especially.
    THE METHOD AND THE APPLICATION OF PARAMETER DETERMINATION FOR IMBIBITION MODEL IN FRACTURED RESERVOIR 
    LIU Lang GUO Xiao ZHANG Cai
    2007, 29(1):  85-87.  DOI: 10.3863/j.issn.1000-2634.2007.01.025
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    Restricted by experimental equipment, methodologies, long period of experiment, high cost and greater errors, a new linear regression method by using reservoir historical production data is derived to determine the model parameters. The models of productivity prediction and the time of maximum imbibition′s rate are then presented. A real reservoir case is calculated and compared using the method. The results show good agreement with reservoir productivity data, which is of reference to the dynamic study on water flooding production of fractured reservoirs. 
    THE RESEARCH ON NEARMISCIBLE MULTICONTACT FLOODING MECHANISM OF INJECTING ASSOCIATED RICH GAS
    PANG Jin SUN Lei SUN Liang-tian LEI Xiao MI Hong-gang
    2007, 29(1):  88-91.  DOI: 10.3863/j.issn.1000-2634.2007.01.026
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    Based on near miscible flooding mechanism, the miscible phase can be achieved with the increase of miscible pressure, even though there is little middle molecular weight of crude oil. High miscible pressure of this kind of crude oil is required, which is hard to be achieved for reservoir gas injection engineering. However, based on nearmiscible flooding mechanism, the nearmiscible flooding of vaporcondensate double mass transportation action under lowest miscible pressure may be formed with wet gas or enriched gas produced by proper choose of composition of gas injected. Its character is the creation of low interface, which can reduce the injection pressure and arrive at the miscible flooding efficiency. Based on a practical reservoir in offshore oil field, the associated rich gas in the reservoir is rejected, through the simulation and experiment of multiplecontact PVT phase behavior and intermiscibility swelling between gas injected and formation oil, the change laws of PVT high pressure physical property and the change characteristic between the formation oil and gas injected during nearmiscible multiplecontact process are described and the near miscible flooding mechanism of associated rich gas injection of marine oil field are explored.
    
    APPLICATION OF THE TECHNOLOGY OF THE DRY GAS INJECTION HUFF AND PUFF ON SINGLE WELL IN KEKEYA GAS CONDENSATE FIELD
    WEI Yun-feng LIU Tong-zhen WANG Xin-yu MU Wei-jun CUI Tao-feng
    2007, 29(1):  92-94.  DOI: 10.3863/j.issn.1000-2634.2007.01.027
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    Using numerical simulation method, the retrograde condensation saturation variety and the development effect of the single well dry gas injection is studied. The huff and buff results show the retrograde condensation liquid concentrates in the formation near wellbore, the maximum saturation is 17%. After the dry gas injection huff and buff in the gas condensate well, the part of the retrograde condensation liquid near the wellbore will be reversevaporized or squeezed to the far formation, the permeability of the layer near the wellbore will be improved and the production capacity of the well will be increased. The eighttime tests of the dry gas injection huff and puff of the gas condensate wells have been done in Kekeya gas condensate field, seven times succeed. The insitu test result shows, the technology of the dry gas injection huff and puff of the gas condensate well can control the damage of retrograde condensation near the well bore, improve or recover the productive capacity, which are of great significance to the development of gas condensate reservoirs.
    油气化学工程与化工
    GASLIQUIDSOLID CATALYTIC OXIDATION DESULFURIZATION OF DIESEL
    TANG Xiao-dong CUI Ying-xian HE Bai LI Jing-jing
    2007, 29(1):  95-97.  DOI: 10.3863/j.issn.1000-2634.2007.01.028
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    Optimal oxidation desulfurization catalyst is sorted out from 7 metal inorganic salts and oxides, gasliquidsolid threephase catalytic oxidation desulfurization of diesel is studied by using pure oxygen,optimal catalyst and different extractants. Experimental results show that sulfur content in the treated diesel can be lowered from 1441μg/g to 262μg/g with desulfurization efficiency of 81.8% when using Al2O3 as oxidizing catalyst and furfural solution containing water as desulfurization catalyst and extractant under the following condition: speed of agitator 700r/min, amount of catalyst 5%, reaction temperature 140℃, reaction time 90min and oxygen pressure 0.6MPa.
    THE EFFECT OF MOLECULAR DEPOSITION FILMING FLOODING AGENT AND QUATERNARY AMMONIUM SALTS ON WETTABILITY OF OIL RESERVOIR MINERALS
    LIU Hong-sheng GAO Mang-lai
    2007, 29(1):  98-101.  DOI: 10.3863/j.issn.1000-2634.2007.01.029
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    Washburn method is applied to investigate the different effect of molecular deposition filming flooding agent (MDFFA), tetraethyl ammonium bromide [(Et)4NB] and hexadecyl trimethyl ammonium bromide (CTAB) on the wettability of oil reservoir minerals. The results show that the oil reservoir minerals absorbed MDFFA or (Et)4NB are more hydrophilic than that of those minerals absorbed CTAB. The hydrophilicity of Daqing and Zhongyuan oil sands rises after absorbing MDFFA or (Et)4NB. The oil wettability of most oil reservoir minerals declines after they absorbed different quaternary ammonium salts. The oil wettability of asphaltene oil reservoir minerals rises after they absorb different quaternary ammonium salts (except for asphaltene kaolin). The oil wettability of Daqing and Zhongyuan oil sands treated by MDFFA before and after adsorb asphaltene are lower than that of those minerals treated by (Et)4NB or CTAB, which are of important significance to water flooding and tertiary recovery. 
    CORE SHEARING RHEOLOGY BEHAVIOR OF ASSOCIATING POLYMER SOLUTION
    YANG Huai-jun ZHANG Jie ZHANG Jing-chun
    2007, 29(1):  102-105.  DOI: 10.3863/j.issn.1000-2634.2007.01.030
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    Effect of rock coreshearing for hydrophobically associating polymer and the ordinary linear high molecule polymer solution on polymer solution rheology behavior is studied, the rheology curves of two types of polymer solution before sheared is tested, and the rheology property is analyzed. Manmade cores are used to test coreshearing, rheology cures of sheared polymer solutions are tested and rheology properties analyzed by comparison. And then, to imitate the situation of polymer solution in the deep oil reservoir after layer shearing, the resistance factor and residual resistance factor experiments of coreshearing polymer solutions are determined. The researches have important value and implications for EOR.
    石油机械工程及其它
    THE DISTRIBUTION LAW OF RADIAL VELOCITY OF FLOW FIELD IN HYDROCYCLONE 
    LIANG Zheng REN Lian-cheng ZHANG Liang YU Yan-lin JIA Zhen-xu
    2007, 29(1):  106-108.  DOI: 10.3863/j.issn.1000-2634.2007.01.031
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    The radial velocity of flow field in hydrocyclones has great influence on the particle radial movement, which decides the degree of resisting particle radial movement and the diameter of the minimum particles the hydrcyclone can separates. Based on the numerical simulation of radial velocity of the flow fluid in hydrdocyclone,the radial velocity of flow in hydrocyclone is studied in the paper. The studies shows that the value of the radial velocity increases first and then decreases gradually along the radius direction inwards, and finally, falls to zero at the liquid/air interface, the two kinds of conclusions are correlated and studied, it is recognized that the Kε turbulence model and the Boussinesq hypothesis are not suitable for the flow field in hydrocyclone. 
    THE STRENGTH AND FATIGUE ANALYSIS OF SPLINE SHAFT OF HQ1400 HIGH PRESSURE PUMP WORM
    ZENG Xing-chang ZHONG Gong-xiang LIANG Zheng
    2007, 29(1):  109-112.  DOI: 10.3863/j.issn.1000-2634.2007.01.032
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    The strength analysis and fatigue analysis are performed by using Pro/E and Pro/M on the base of material analysis, mechanical performance test and loading analysis. The authors confirm that breaking mechanism of spline shaft is fatigue breaking, and put forward corresponding measures to solve the problem from the aspects of designing, material choosing, manufacturing, and controlling quality etc,it is recognized in manufacturing spline shaft, 50CrMoA should be chosen and tempered with the addition of surface hardening, and S, P, Cu content in steel should be controlled, the diameter of spline shaft and the tooth root radius should be increased to increase the reliability and life of the spline shaft.
    
    THE POSITIVE RESEARCH ON THE COST DRIVER OF DRILLING OILGAS WELL
    FAN Ming-wu LI Zhi-xue FENG Li-dan
    2007, 29(1):  113-117.  DOI: 10.3863/j.issn.1000-2634.2007.01.033
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    Oil and gas well drilling operation is taken as an example to analyze the feasibility of applying ActivityBased Cost to the petroleum and natural gas industry in China, probes into the cost driver of drilling cost of influencing the well drilling operation of oilgas. On the basis of analyzing the drilling cost influence factors, three assumptions to the drilling operation process are proposed: (1) The drilling cost of different well type structure is different; (2) there is a certain proportionate relationship between the drilling cost and drilling penetration; (3) there is a certain proportionate relationship between drilling cost and the cycle of drilling. Authors use the analytical statistics method to set up regression model and examine these three assumptions , by the constant try, the optimal model of well drilling cost of oil gas is sort out for oilgas drilling cost predicting and planned management, valuable accounting information is provided to the decisiomaking and control of oilgas enterprises.
    基础理论
    PRESSURE DISTRIBUTION SOLUTION OF SAELED RESERVOIR WITH COMPOSITE DUAL PERMEARBILITY
    WU Di HUANG Bing-guang LI Shun-chu WU Tie- ming WANG Nu-tao
    2007, 29(1):  118-122.  DOI: 10.3863/j.issn.1000-2634.2007.01.034
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    Aimed at the sealed reservoir model with composite dual permeability, the Laplace space solution of dimensionless pressure distribution of variable flow rate under the condition of two types of interior boundary is studied, and on the basis of deeply probing the structure and the relationship of the solution, the relationship between the solution and composite dual permeability and homogeneous reservoir pressure distribution is figured out. The well test analysis theory is further improved, and the method is very valuable to the development of the corresponding well test software, meanwhile, it is also meaningful to numerical simulation of reservoir engineering.
    EXISTENCE ANALYSIS OF DEFORMED DUAL MEDIA FLOW THROUGH POROUS MEDIA SOLUTION
    ZHANG Jin-liang ZHANG Lie-hui HE Guo-liang ZHANG Jun-liang
    2007, 29(1):  123-125.  DOI: 10.3863/j.issn.1000-2634.2007.01.035
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    The nonlinear flow through porous media mathematic model of deformed dual media fractal reservoir, based on WarrenRoot model and the introduction of fractal parameters and compression coefficient, takes the influence of pressure on permeability and porosity with fractal feature into consideration. The existence of the solution of the differential equation of the model is probed according to discrete functional analysis and the fixed point theory. It is indicated that in correctly recognizing the complex heterogeneous oil reservoirs and stresssensitive formation oilgas reservoirs, fractal geometrical theory and the method are of unique advantage.
    博导论评
    THE FEASIBILITY OF MICROORGANISMCO2 COMPOUND FLOODING IN PRODUCTION NEAR SHORE HEAVY OIL FIELDS
    GUO Ping LI Miao ZHANG Ting-shan
    2007, 29(1):  126-129.  DOI: 10.3863/j.issn.1000-2634.2007.01.036
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    Aimed at such problems in heavy oil production near shore as low primary and secondary recovery efficiency, high viscosity difference, easy water breakthrough, many producing pays, serious reservoir heterogeneity, high producing pressure difference, severe fine particle migration in the reservoir, severe nearbore plugging caused by organic settlement of colloid and asphalt, the new method of microorganismCO2 compound flooding is suggested. The article separately summarizes the heavy oil development ways and application state of microorganism injection and CO2 flooding, analyzes the feasibility that microorganismCO2 compound flooding develops heavy oil fields and then puts forward the problems that need being solved when using the new method. The method is of very important value and popularization in the development and enhanced oil recovery of heavy oil.
    探讨与争鸣
    ANALYSIS ON WATER CUT IN MUDSTONE AND THE ABNORMAL FORMATION PRESSURE
    LI Chuan-liang
    2007, 29(1):  130-132.  DOI: 10.3863/j.issn.1000-2634.2007.01.037
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    Mudstone is a kind of clastic rock, which possesses pores and porosity, there is also permeability, but its permeability is quite poor due to the extremely small openness of pores. Mudstone can definitely transport water with poor permeability. Oil wells usually produce a little quantity of water at beginning of production, which comes from the mudstones lying over and under the reservoirs, not the formation water dissolved in crude oil. The abnormal pressure in formations is resulted from the geological accidents, and is a temporary status of pressure, which is so far not balanced by water transportation in mudstones during short time.

    封面人物
    Cover Profile
    2007, 29(1):  200-201.  DOI: 10.3863/j.issn.1000-2634.2007.01.100
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    Luo ping-ya, male, Han nationality, a Communist Party member, was born in July 1940 in Changlong Sichuang Province. Professor, the tutor of doctor, the academician of the Chinese Academy of Engineering, the Former President of Southwest Petroleum University, the Former Director of the Academic Committee in the State Key Laboratory of "Oil and Gas Reservoir Geology and Exploitation" . For the past 40 years, he has been committed to the teaching and research on the exploration and exploitation of Oil and Gas and has Obtained lots of great achievements on fields such as, drilling and completion fluid technique, reservoir protection technique, theory and application technique on oilfield chemistry. These achievements are mainly summarized as follows:
    First, study on deep wells drilling fluid with high temperature resistance: In the mid-1970s, he proposed to improve the performance of the mud taking the advantage of high temperature and established the new ultra-deep mud system (anti-high temperature sulfonated mud system) of "the more deep the well, the higher the temperature, the longer the action time, the better the performance, the more simple the process, the lower the cost " , providing the necessary technical support for the success of deep well drilling. This system is still the main component of deep well mud technology in China and has been widely used.
    Second, Polymer Mud Technology: During the 1980s, he advanced that amphoteric polymers can be used for drilling mud agent and developed a series of new polymer treating agents and matching technology, which is one of the main components and development direction and is still being widely used.
    Third, Drilling and Completion fluid technique for reservoir protection: He proposed the point of shielding temporary plugging technique for reservoir protection and developed matching technology series, which solved the reservoir protection problems when drilling in oil layers using drilling fluid under positive pressure gradient and made great economic and social benefits. This technology is still being widely used.
    Fourth, the development of water-soluble polymer with heat and salinity tolerance, anti-shearing, efficient and viscosified: It provides the necessary theoretical basis and material guarantee for the establishment of various of displacement fluid system which is suit for enhancing recovery by chemical flooding in China.
    Besides, he also obtained great achievements on hole stabilization, horizontal drilling technology, oil-displacement mechanism by chemical flooding, application of seepage of physical chemistry, reservoir protection technology during oil production, Theory and Application Techniques of oilfield applied chemistry engineering and so on.
    He has presented and accomplished more than 40 research tasks belonging to Ministerial and provincial levels and obtained more than 30 awards of science and technology (including excellent teaching achievements) of which include 7 national awards and 13 Ministerial and Provincial Level awards( of which 3 are rated as CNPC ten annual excellent results ) and published 6 works and more than 100 papers, as well as cultivated more than 90 masters and doctors.
    Since he has obtained series of outstanding achievements both in scientific research and teaching, he is commended 6 times by government and rated as model worker and advanced teacher belonging to Ministerial and Provincial Level. He was granted as A NATIONAL JUNIOR EXPERT OF OUSTANDING CONTRIBUTION in 1986 and was approved AN EXPERT ENJOYING SPECIAL GOVERNMENT ALLOWANCE in 1990. He obtained Sun Yue-qi Energy Award in 1993 and became the academician of the Chinese Academy of Engineering in 1995. He is also the member of the third and fourth subject review groups of the State Council High Degree Committee, the member of High Degree Committee in Sichuan province, deputy to the sixth and seventh NPC, deputy to the sixth Sichuan provincial Party Congress and the 2000th national advanced worker.

    本期导读
    Volume Head
    2007, 29(1):  201-202.  DOI: 10.3863/j.issn.1000-2634.2007.01.101
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    University journal is not only the signboard of a university but also one of the main contents to examine and measure the quality of a university. To trustily record the historical scientific personnel, case, and academic idea sparks is decided by historical culture attribute of the University Journal. How to make the window attribute, forum attribute, and historical culture attribute band organically to keep pace with times, promote social progress and display school’s characteristic is the theme for the journal manager and journalists to show their wisdom.
    Times pulse shows as follows: globalization, scientific development, and harmonious society. Social progress presents at the progress on science and technology, material civilization and spiritual civilization. School characteristic shows at oil and gas, western China and university.
    Globalization demands the reported content, author, evaluation experts and editorial board globally.
    Scientific developments need us to check the innovative academic idea and technology in the view of development, to direct the publication management concept with system theory, avoiding low level, tracking, plagiarism.
    Harmonious society asks us to admit difference, allow hundred flowers and establish the system.
    The progress on science and technology should be presented in the thesis and the abundant appearance of technical diagrams requires our true reflects.
    The progress on material civilization is embodied in the betterment of material development and material life. We wish the increasing income for every scientific worker and hope they can perceive the improvement of the material civilization.
    The progress on spiritual civilization is embodied in the development of spiritual production and spiritual life. We wish scientific workers have an improvement in study, work and living environment and happy every day and no spiritual burden in a new year.
    Oil and gas is the important mineral resources in the world and the advantage subject in our school for fifty years construction.
    Western China is the geographic attribute for our school. Ministry of Science and Technology clearly put forward the strategy thought of scientific and technological innovation, scientific and technological plan, scientific and technological antecedent in August 2000 in “Advice On Strengthening the Science and TechnologyWork of Western Region” . Our journal should insist on scientific spirit and scientific attitude to make contribution for the western development.
    College culture construction is the foundation and soul for the survival and development of the college. College culture construction is embodied partially in the study field, research result, subject construction, learning master, historical figures and representative excellent graduates and so on. University journal should have function bearing these tasks.
    Therefore, we are planning to take measures as follows from this current period:
    (1)The new composition of the members of editorial board, decreasing domain, embodying the characteristic of western, oil, university, global as possible.
    (2)To accomplish color printing of the paper periodical so as to reflect the level of academic thought and research results.
    (3)Carrying out network journal running. So as to shorten the delay in publication of articles, quicken the propagation velocity of the journal, widen the propagation range and enlarge the journal effect.
    (4)Implementing the plan of cover character. Heading for different subject directions, section for new thought, new method, new technology and new results, based on the basis of the combining of old, junior and youth and the frontier science and technology characters first.
    (5)Keeping the characteristics column. Oil an gas engineering is our brand course as well as this journal’s characteristic column. In the New Year, we will keep columns like oil an gas engineering and carry forward academic research and concern oil and gas development.
    (6)Adding experts’ forum. Publish the original understanding of the experts with scientific and technological achievements in the front line of scientific research.
    (7)Setting up PhD supervisor’s comments. Publish mainly the thought, method, comment and summary of the tutor of doctor working in front line in academy and technology.
    (8)Establishing PROBE AND CONTENDS and the atmosphere of harmonious society to make the journal the culture garden for new science idea and arena for challenging the old authority arguments.Works with sharp viewpoint and Unique perspective can be published there.
    Besides, this journal presents columns such as “hydrocarbon reservoir management”, “calculation technology for oil engineering”, “oil and gas field material and its application, and basic theory”. We are planning publish two supplements for reader every year.
    Looking forwards to your criticism and instruction for these attempting.