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01 April 2009, Volume 30 Issue 2 Previous Issue    Next Issue

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Hydrocarbon Enrichment and Exploration Domains in Mid-Western Tabei Uplift,Tarim Basin WANG Zhao-ming, HE Ai-dong 2009, 30 (2):  153-156.  Abstract ( 87 )   PDF (253KB) ( 208 )   Save The mid-western Tabei uplift in Tarim basin is in good prospects for petroleum exploration, but has complex petroleum geological features. The regional geologic data analysis indicates that the mid-section of south Tianshan oceanic basin was formed in Late Ordovician-Early Silurian, and Tabei slope was good geological background for oil-gas enrichment in this area. It is indicated from Yingshan formation source rock samples of Ha-6 Well that the organic carbon content in its dolomitic limestone with thickness of 130 m is higher than 0.5%, showing the Lower Ordovician in this area belongs to commercial source rocks, which could broaden the depth and domain of exploration here. Study shows that the mid-western Tabei uplift is of conditions of complex paleo-karst system, along the unconformity and adjacent pinch-out are favorable areas for large-scale paleo-karst oil-gas reservoirs; the Cambrian fold in western Yingmaili swell is of premium conditions of petroleum accumulation and preservation, being a new and potential domain for petroleum exploration. Also, the buried hill area in Yingmaili swell is still of some explorative potential due to its partial and favorable control factors on petroleum accumulation. References | Related Articles | Metrics

Probe into Exploration Prospect of Cambrian Subsalt Carbonate Rocks in Tarim Basin from East Siberia Basin LV Xiu-xiang, BAI Zhong-kai, FU Hui 2009, 30 (2):  157-162.  Abstract ( 162 )   PDF (646KB) ( 505 )   Save East Siberia basin and Tarim basin are all ancient craton basins where a series of oil-gas fields have been found, with different scales and reserves. The correlation of hydrocarbon accumulation and major control factors between these two basins indicates that there exist premium source rocks and reservoirs in subsalt carbonate rocks of Cambrian in these basins, and regionally distributing gypsum-salt rock of Middle Cambrian is good cap rock. The study shows that the subsalt carbonate rocks of Cambrian in Tarim basin possess favorable exploration prospect, the favorable areas or zones are located in the main host belts of Tazhong uplift and its two sides, Yingmaili and Lunnan areas in Tabei uplift and southern structural belt of Bachu swell, based on the source-reservoir-cap rock assemblage, structural development, sedimentary environment, oil-gas shows and the petroleum accumulation characteristics of the two basins. References | Related Articles | Metrics

Key Tectonic Changes and Staging Differential Structural Deformation in Superimposed Basins TANG Liang-jie, JIN Wen-zheng, HE Chun-bo, CUI Min, NING Fei, WAN Gui-mei 2009, 30 (2):  163-167.  Abstract ( 87 )   PDF (412KB) ( 269 )   Save Key tectonic changes in superimposed basins can be classified as uplifted and eroded change, continental-oceanic transform change and thrust-fold change, and the several control factors for them include transform of tectonic stress field transform, change of deep dynamic procedure and transform of deep thermal system, etc. Such changes make superimposed basins have distinct features of staging differential tectonic deformation. The main features of those basins in China are as follows: uplifting and eroding in Caledonian stage, uplifting-eroding and thrust-fold in Hercynian stage, continental-oceanic transform in Hercynian and Indosinian stages, thrust-fold in Yanshan and Himalayan stages, with manifestations of migration and superimposition in structural deformation, variation of basin structure, formation of regional unconformity, migration, compression, extension and transform of basin boundary as well as change of basin-mountain framework, etc. References | Related Articles | Metrics

Petroleum Accumulation Geologic Condition and Explorative Prospect of Silurian in Tarim Basin WANG Qing-hua, TANG Zi-jun, ZHAO Fu-yuan, ZHU Yong-feng, LI Hui 2009, 30 (2):  168-170.  Abstract ( 100 )   PDF (232KB) ( 221 )   Save The Silurian system in Tarim basin is an important domain for exploration of big oil-gas field for its large area and enriched oil-gas shows. With the increase of exploration extent, stratigraphic-lithologic hydrocarbon reservoirs have already become leading aspect for finding oilfield of it. At present, the commercial producing horizons mainly focus on the upper member of Kepingtag formation. The effective reservoir rock is sandstone with quartz content of over 65% formed in tide-flat, shore and delta environment. The study shows that multiple transgression and regression cycles caused by the fluctuating changes of sea level are favorable to formation of multi-set reservoir-cap rock assemblages and stratigraphic-lithologic traps; well preservable primary paleo-oil reservoir may exist in the sag hinterland; recharging of hydrocarbon during Yanshan-Hilalayan movement forms the non-structural reservoirs of unconformity barrier in Tabei area and stratigraphic overlap in Tazhong area, indicating its broad exploration prospect. References | Related Articles | Metrics

Significance of Hercynian Movement in Hydrocarbon Accumulation in Tarim Basin LI Qi-ming, CAI Zhen-zhong, TANG Zi-jun, ZHOU Yong, HU Jian-feng, LI Bao-hua, WU Min 2009, 30 (2):  171-174.  Abstract ( 98 )   PDF (295KB) ( 429 )   Save The Hercynian movement is a significant event for tectonic evolution in Tarim basin. The paleohighs adjacent the source center in this period should be long-term objective area for hydrocarbon migration; the existing faults and karstification provided channels and pore volumes for petroleum migration. The relative stability of late tectonic movement and the superposition of regional shale cap rocks constituted effective reservoir-cap rock system with carbonate cavities, which just matched the Hercynian oil-generating peak of Middle- Lower Cambrian source rocks, being favorable to the formation and preservation of large oil-gas fields in this area. According to petroleum distribution rule of "oils controlled by paleohighs and enriched by slope belt", it is concluded that Tazhong, Lunnan, Yingmaili and Bachu paleohighs or uplifts are most favorable domains for further petroleum exploration. References | Related Articles | Metrics

Control Effect of Neotectonic Movement on Hydrocarbons in Tarim Basin XU Han-lin, JIANG Tong-wen, GU Qiao-yuan, ZHANG Xiao-fang, WU Min 2009, 30 (2):  175-178.  Abstract ( 76 )   PDF (416KB) ( 274 )   Save The neotectonic movement around Tarim basin assumes intense thrust nappe structure. The Xiyu formation of Lower Pleistocene (Q1x) in different areas around the basin thrusts into different strata or is covered by old strata in different ages and rolled into folds in different scales. 3D seismic interpretation indicates that regional tectonic inversion occurs in strata above Silurian system in Tarim platform area owing to neotectonic movement, leading to southward migration of top structural highs in different horizons. The neotectonic movement has two effects on controlling hydrocarbons in Tarim basin. One is that some large-scale structural traps favorable for late-stage hydrocarbon accumulation were formed around this basin and provided huge power for hydrocarbon migration in late stage. The other is the movement changed and reconstructed the trap conditions of ancient oil reservoirs shaped in early stage, resulting in the hydrocarbon remigration in them and consequently forming new oil reservoirs with complex oil-water contact and still being charged with fluid nowadays. References | Related Articles | Metrics

Spatial and Temporal Characteristics of Permian Large Igneous Province in Tarim Basin CHEN Han-lin, YANG Shu-feng, LI Zi-long, YU Xing, LUO Jun-cheng, HE Guang-yu, LIN Xiu-bin, WANG Qing-hua 2009, 30 (2):  179-182.  Abstract ( 193 )   PDF (349KB) ( 571 )   Save The magmatism of Permian large igneous province (LIP) is a very significant thermotectonic event in process of evolution of Tarim basin. The lithological units of this province consist of brecciated mica-olivine pyroxenite pipe, olivine pyroxenite, pyroxenite, gabbro, basalt, diabase, alkali syenite and syenite dike, being dominated by basalt and diabase. They are not only distributed in the west part of Manjiaer depression and west part of Tabei (northern Tarim) uplift, but also in Tazhong (central Tarim) uplift, Buchu uplift and Taxinan (southwestern Tarim) depression, covering an area of 20×104 km 2 , and there are also 7 thickness centers for residual distribution. The time sequence of the Permian LIP development is as follows: Wajilitag layered rock mass→brecciated mica-olivine pyroxenite pipe→ basalt of Kupukuciman formation (278-292 Ma) →basalt of Kaipaicileike formation (272-288 Ma) →diabase and ultrabasic dikes→ syenite (quartz syenite porphyry) (277 Ma). References | Related Articles | Metrics

Sedimentary Characteristics and Tectonic Evolution of Jurassic in Southeast Depression,Tarim Basin— An example from Ruocan-1 Well LUO Jun-cheng, SUN Xiong-wei, JU Yan, LI Ming-he 2009, 30 (2):  183-185.  Abstract ( 91 )   PDF (299KB) ( 227 )   Save Based on the core, logging and well log data, integrated with available seismic interpretation results, in-depth study of sedimentary characteristics and sedimentary facies distribution of Jurassic in southeast depression of Tarim basin is made, including the relations between sedimentary facies variation and tectonic evolution. The study shows that in Early-Middle Jurassic, Ruoqiang sag was a fault basin with alluvial fan and braided river delta deposits in Early Jurassic, braided river delta and lacustrine deposits in Middle Jurassic; in Late Jurassic, it became a downwarping basin dominated by fluvial deposit. Ruoqiang structural belt and Minnan structural belt are favorable areas for petroleum exploration References | Related Articles | Metrics

Balanced Structural Section Analysis of Wuboer Structural Belt in Tarim Basin WANG Bu-qing 2009, 30 (2):  186-187.  Abstract ( 131 )   PDF (275KB) ( 189 )   Save Based on the field geologic investigation data, the seismic reflection features of target zones and tectonic deformation theory on orogeny, the structural interpretation model for Wuboer structural belt in southwestern Tarim basin is developed. And this model is analyzed using software 2DMove for structural section balance and restoration. The generally balanced structural model reveals that with tectonic uplifting since Late Pliocene, the Cenozoic strata are subjected to denudation, indicating that in Cenozoic the strongest movement occurs in Late Pliocene. References | Related Articles | Metrics

Conodonts from Baiyungang Formation in Queerqueke Section in Southern Kuruktag Area,Xinjiang GUO Wei, HE Shun-li, ZHAO Zong-ju, TAN Ze-jin 2009, 30 (2):  188-193.  Abstract ( 104 )   PDF (1145KB) ( 249 )   Save This paper presents the conodonts collected from Baiyungang formation in Queerqueke mountain, southern Kuruktag area in Xinjiang, consisting of 19 species and 3 undetermined ones, belonging to 14 genuses. They are classified into 6 conodont zones from bottom to top, such as Proconodontus posterocostatus zone, Proconodontus muelleri zone, Eoconodontus notchpeakensis zone, Cordylodus proavus zone, Cordylodus lindstromi zone and Cordylodus angulatus zone. Based on these conodont zones, the Cambrian-Ordovician boundary in this area is preliminarily determined. References | Related Articles | Metrics

The Karst Log Response of Carbonate Rocks of Lower Ordovician in Tazhong Area,Tarim Basin LIU Xing-li, ZHANG Gui-bin, LI Duo-li, LI Hua-wei 2009, 30 (2):  194-196.  Abstract ( 130 )   PDF (575KB) ( 293 )   Save On the basis of research of control factor and distribution characteristic of the karst weathering crust development of Lower Ordovician carbonate rocks in Tazhong area, integrated with conventional well logs, the karst is divided into hypergene karsts, vertical percolation karsts and horizontal underwater current ones. Also, the electric imagine chart and the log response mode are built up using natural gamma ray spectrometry logs, dual laterologs and porosity logs. The lateral correlation study of the karsts in 4 wells is conducted. References | Related Articles | Metrics

Interpretation of Imaging Logs of Sedimentary Microfacies of Reef-Flat Reservoir in Tazhong No.1 Slope Break Zone, Tarim Basin LI Duo-li, LIU Xing-li, ZHONG Guang-fa, GUO Xiu-li 2009, 30 (2):  197-200.  Abstract ( 88 )   PDF (481KB) ( 289 )   Save This paper proposed the definition of electric imaging logging faces of carbonate rocks, presents a set of logging facies classification system suitable for geologic study, the electric imaging response features of various sedimentary microfacies and builds up the models for corresponding logging facies, based on characteristics and electric imaging logs of the sedimentary microfacies of reef-flat reservoir in Tazhong No.1 slope break zone, Tarim basin. Through continuous logging-facies classification and sedimentary microfacies interpretation for single well, the relation of logging facies and reservoir physical property is statistically analyzed. References | Related Articles | Metrics

Effect of Gypsum-Salt Rocks on Hydrocarbon Accumulation in Kelasu Structural Belt of Kuqa Depression YANG Xian-zhang, LEI Gang-lin, ZHANG Guo-wei, ZHAO Dan-yang 2009, 30 (2):  201-204.  Abstract ( 97 )   PDF (425KB) ( 232 )   Save The study shows that the Paleogene gypsum-salt rocks of Kelasu structural belt in Kuqa depression has a significant effect on hydrocarbon accumulation in this area: 1)the regional distributing thick gypsum-salt rocks could provide premium conditions for subsalt trapping; 2)the petrophysical property of the rocks, such as low density, high thermal conductivity, poor insulation, strong plastic flow and effectively releasing lateral squeeze stress, is favorable for protection of the deep reservoir's porosity and permeability; 3)the strong plastic flow prevents from damages of tectonic compression to subsalt structural traps, and helps preservation of large traps and dependence of gypsum-salt zone on the traps. The result shows that in-depth study of the spatial distribution and petrophysical property is of great significance for further petroleum exploration in this area. References | Related Articles | Metrics

Post-Stack Seismic Data Management and Quality Control Regulation in Tarim Oilfield LI Shi-ji, GAO Hui, CAO Yu, ZHANG Yao-tang, LI Wen-yu 2009, 30 (2):  205-207.  Abstract ( 100 )   PDF (170KB) ( 249 )   Save With the experiences of post-stack seismic data management, Taim Oilfield Company has made strict criteria for storage of the seismic data. From the basic theory of seismic exploration, this paper presents the practical rules for quality control and derives the equation for computation of the theoretical 3D grid definition. A large number of abnormal data is also corrected. It is indicated that this scheme is feasible for application. References | Related Articles | Metrics

Prediction of Seismic Facies and Favorable Prospecting Areas of Triassic in Awati Sag, Tarim Basin DANG Qing-ning, ZHAO Kuan-zhi, SUN Song-wei, ZHU Chang-jian, LIU Yong-fu, XIANG Dong, CUI Yong-fu, ZHAO Wei 2009, 30 (2):  208-210.  Abstract ( 102 )   PDF (540KB) ( 319 )   Save Based on sequence stratigraphy method, the Triassic in Awati sag is divided into four Class-III sequences. In view of internal texture and external configuration, integrated with reflection continuity, reflection amplitude and frequency, five types of major seismic facies are distinguished from the seismic profile, such as parallel sheet seismic facies with high amplitude and high continuity, parallel- subparallel sheet facies with medium amplitude and medium continuity, subparallel facies with mid-low amplitude and low continuity, chaotic reflecting facies and progradational facies. These seismic facies assume obvious distribution in plane and differential and successive features in vertical direction, and have good correlations with Awati sag structure and tectonic evolution in Tarim basin. References | Related Articles | Metrics

Structural/Sedimentary Environment and Hydrocarbon-Generating Potentials of Carboniferous in Junggar Basin JIN Jun, ZHANG Chao-jun, LIU Luo-fu, LIU He-jiang, ZHANG Li-ping 2009, 30 (2):  211-214.  Abstract ( 90 )   PDF (370KB) ( 300 )   Save Carboniferous epoch is the conversion period of tectonic geologic environment in Junggar basin, in which land mass splicing was accompanied with a large number of gulfs; coastal marshes were formed by continental-oceanic transition, being favorable to development of source rocks; coexisting rifted and island-arc types igneous rocks constructed multi-type reservoir bodies. Such a change of geologic environment created conditions for development of multi-set source rocks of Carboniferous in Junggar basin, while the abroad deposition added its petroleum resource potentials and explorative ranges. The study shows that there exist multi-set source rocks in Carboniferous with high organic matter abundance, possessing material bases for forming large reservoirs. It is concluded that Eastern Junggar-Wucaiwan is a realistic area for natural gas exploration; the lower wall of thrust fault belt in northwestern margin of Junggar basin is of large potentials for petroleum exploration; the hinterland and southern part of this basin are of great prospects for it, hopefully discovering large- and medium-sized oil-gas fields; the explorative potential of Wulungu area should not be overlooked. References | Related Articles | Metrics

Remaining Oil Distribution and Impact Factors in Mouth Bar Sands—— — An example from Shengtuo field in Dongying sag SUN Yu-hua, XIN Zhi-guo 2009, 30 (2):  215-218.  Abstract ( 102 )   PDF (363KB) ( 223 )   Save Mouth bar can be divided into single and overriding types. In this paper, 18 conceptual models are set up according to different thicknesses, permeabilities, interbedded rhythms and injection-production conditions, and simulated by limiting water cut of 98%. The simulated result presents the impact factors and the distribution mode of remaining oil in mouth bar. And the most important factors are permeability contrast and reservoir permeability rhythms up and down interbeds. Furthermore, the single type of mouth bar sand is subdivided into top enrichment model, homogeneous displacement model and bottom enrichment model for remaining oil; the overriding type is subdivided into above-interface, below-interface and above- and below-interface enrichment models. References | Related Articles | Metrics

Groundwater Nature and Exploration Domain in Chepaizi Field ZHAO Wei-jun, ZHI Dong-ming, XU Qun-zhou, HE Lu-ming, DONG Xue-mei 2009, 30 (2):  219-220.  Abstract ( 109 )   PDF (169KB) ( 338 )   Save In view of formation water and crude oil physical properties from all sequences in Chepaizi oilfield of Junggar basin, it is considered that the enclosed environments from Carboniferous to Cretaceous are worse and worse, among which Jurassic is the most perfect oil-bearing reservoir as a transitional zone from enclosed environment to open environment. It is concluded that the formation water type can be used to judge the enclosed quality of fault or fracture. The Jurassic in A zone of Chepaizi oilfield is enclosed and that in B zone is open, so the former (A zone) could be the main target for petroleum exploration in this field. References | Related Articles | Metrics

Using Optimized Seismic Attributes to Predict Reef Reservoir YU Xiao-wei, ZHENG Xiao-dong, LI Yan-dong, YANG Hao 2009, 30 (2):  221-224.  Abstract ( 112 )   PDF (534KB) ( 322 )   Save In view of relations between paleogeomorphology, sedimentary facies and seismic attributes, this paper presents multi-attribute cluster analysis method and demonstrates its rationality under constraining condition of paleogeomorphology. The optimized seismic attributes followed by cluster analysis can be applied to prediction of reef reservoir and fluid property. The case study from Sichuan basin shows that such a multi-attribute cluster analysis method can effectively characterize the favorable facies, physical peature and partial fluid characteristics of reef reservoir. References | Related Articles | Metrics

Wellbore Performance Analysis and Software Development of Dina-2 Condensate Gas Field with Abnormal High Pressure JIANG Tong-wen, CHANG Zhi-qiang, XIAO Xiang-jiao, TANG Ming-long, YANG Jian-ping, WANG Hong-feng 2009, 30 (2):  225-227.  Abstract ( 79 )   PDF (271KB) ( 202 )   Save Dina-2 gas field is a deep and abnormal high pressure condensate reservoir, and the pressure behavior monitoring in wellhead results in an abnormal occurrence. According to the wellbore temperature profile, this paper presents new reduced pressure formula considering phase behavior change, dynamic friction coefficient and kinetic energy loss, and develops the corresponding software, obtaining more perfect performance analysis method for abnormal high pressure condensate gas well. The case study shows the model is of high reliability and practicability. References | Related Articles | Metrics

Regulation of Horizontal Well Producing Pressure Differential in Unsaturated Reservoir ZHU Wei-hong, WANG Tao, RUAN Yang, ZHANG Jin, ZHANG Jian-hua 2009, 30 (2):  228-231.  Abstract ( 91 )   PDF (314KB) ( 257 )   Save HD water drive sandstone reservoir in Tarim basin is a complex reservoir with water cut differential in different areas controlled by structure and stratigraphy, which is developed by horizontal wells on the whole. Based on the percolation law of horizontal wells, integrated with performance monitoring data from the fluid producing section logging and production testing of horizontal wells, this study reveals that the differential of skin effects within horizontal intervals is an essential reason for aggravating or weakening the intrastratal contradictions. And the effect of regulating producing pressure differential on development effectiveness is studied for guiding related production and measure regulation, keeping the production stable while bringing the water-cut under control as well as highly effective development by horizontal wells in this area. References | Related Articles | Metrics

Method for Prediction of Borehole Performance in Condensate Gas Well HE Zhi-xiong, SUN Lei, WANG Lei, LIN Tao, LIU Zhi-bin 2009, 30 (2):  232-234+278.  Abstract ( 82 )   PDF (264KB) ( 288 )   Save When producing, the temperature, pressure, compositions and molar fractions of gas and liquid as well as liquid loading in different places of a condensate gas borehole are changing with changes of oil, gas and water production rates. The vertical conduit flow and borehole carrying fluid computational formulae by state of flow, considering borehole temperature change, and combining with thermodynamic flashing calculation for fluid phase equilibrium, this paper proposes the method for prediction of borehole performance in condensate gas well. The case calculated results show that this method as a guide for production of such a well can be used to predict these temperature, pressure, compositions and molar fractions of gas and liquid as well as liquid loading situation in different places of a condensate gas borehole in different production stages. References | Related Articles | Metrics

Application of Relative Permeability Curves to Establishment of Empirical Formulas for Fluid Productivity Index and Injectivity Index of Horizontal Well WANG Tao, ZHU Wei-hong, YANG Sheng-lai, BAI Qiu-yan, LI Ji-ping, WU Min 2009, 30 (2):  235-237.  Abstract ( 158 )   PDF (210KB) ( 532 )   Save The thin-sandstone reservoir of HD oilfield in Tarim basin is characterized by dual payzones, ultra-deep and ultrathin laminar reservoir with medium-low permeability and edge water. It is developed by water injection technology of double-step horizontal wells. This paper gives the empirical formulas for horizontal well's fluid productivity index and injectivity index changing with water cut applying the relative permeability curves. The case study indicates that these formulas are practicable for prediction of injection-production capacity, rational regulation of injection-production strategy and EOR by horizontal well water flooding in this reservoir. References | Related Articles | Metrics

Enhancing Oil Recovery of Condensate Gas Reservoir by Horizontal Wells CHANG Lun-jie, XIAO Xiang-jiao, BIAN Wan-jiang, LIN Na 2009, 30 (2):  238-240.  Abstract ( 76 )   PDF (288KB) ( 158 )   Save This study shows that for condensate gas reservoir with bottom oil, utilizing horizontal well pattern, the oil recovery could be effectively enhanced by producing bottom oil followed by producing upper condensate gas without impacting the gas recovery. Taking Yingmai-7 condensate gas pool as an example, such an effectiveness could be reached by the process that the horizontal well is positioned at 1~2 m above gas-oil contact, with horizontal interval length of 300 m and the oil production rate less than 2.5%. References | Related Articles | Metrics

A Study of Alkali Free Polymer-Surfactant Compound System for EOR LI Zhao-xia, ZHANG Xin-chun, LIU Ren-qiang, MA Wen-guo 2009, 30 (2):  241-243.  Abstract ( 81 )   PDF (291KB) ( 380 )   Save ASP compound flooding with alkali arouses dispersion and migration of in-situ clay, forming alkali scale leading to formation permeability loss, viscoelasticity decrease of polymer solution, and thus reducing sweep efficiency. This paper presents the alkali free polymer-amphoteric surfactant compound system for EOR by visible simulation and artificial core oil-displacement experiments. The study shows that the mobility control characteristic of polymer and the ultra interfacial tension characteristic of surfactant can be fully utilized in residual oil displacement after water flooding, indicating the sweep efficiency of such a system is higher than that of single surfactant system or single polymer system. References | Related Articles | Metrics

Experimental Study of Wax Precipitation in Gas Condensate with High Temperature, High Pressure and High Wax WANG Yi-zhong, SONG Wen-jie, JIANG Tong-wen, MI Ji-liang 2009, 30 (2):  244-246.  Abstract ( 104 )   PDF (258KB) ( 226 )   Save The study of wax precipitation in gas condensate with high temperature, high pressure and high wax from Tarim basin indicates that the phase behavior of such a gas condensate is extremely complex under different temperatures and pressures, showing gas, liquid, gas-liquid, gas-solid and gas-liquid-solid phases. The pressure has a distinct influence on the temperature of the wax precipitation: when the pressure is high, the influence is not clear; when it is close to dew point pressure, the temperature goes up with the drawdown of pressure; when it is lower than dew point pressure, it goes down with the decrease of pressure. References | Related Articles | Metrics

Fine Characterization of Triassic Reservoir in Wellblock No.2 in Lunnan Oilfield HAN Tao, ZHU Wei-hong, CHANG Lun-jie, LIAN Zhang-gui, NIU Yu-jie, LIU Yong 2009, 30 (2):  247-248+251.  Abstract ( 77 )   PDF (278KB) ( 275 )   Save Based on well logs and performance data, integrated with core observation, deposition and diagenesis analysis, this paper builds up the geological model for Triassic reservoir and presents an interpretation of the sand connections in geologic origin. It is pointed out that the intercalated bed in Wellblock No.2 of Lunnan oilfield can be divided into calcareous one, fine self calcite cementing one and fine adjacent calcite cementing one. On the basis of the fine characterization of reservoir, the subdivided sequence development adjustment project of oil measure-I in this well block is proposed, and good results for application are obtained. References | Related Articles | Metrics

Cementing Evaluation of Gas Reservoirs with Abnormal High Pressure XIAO Cheng-wen, LI Jin-fu, YUAN Shi-jun, WU Xing-neng 2009, 30 (2):  249-251.  Abstract ( 83 )   PDF (369KB) ( 422 )   Save The gas reservoirs discovered in Kuqa foreland basin are almost abnormal pressure reservoirs with deep burial (over 3 500 m in general), high pressure, complicated hole structure and equipped with dual or multiple zone casing. With bringing into development/ production of Kela, Dina and Yingmaili gas fields one by one, much higher requirement is needed for such a cementing quality evaluation. In view of the geological and engineering characteristics of abnormal pressure gas reservoirs, the comparison and analysis of methods for cementing quality evaluation in different logging series are conducted, followed by selecting segmented bond tool (SBT) as a premium series. Also, the evaluating methods for cementing quality of dual-zone casing and gas invasion in high pressure gas reservoirs are reviewed in order to provide technological support for evaluations of cementing quality in Kela and Dina gas fields, including making development scheme and realizing safe and stable production of them. References | Related Articles | Metrics

Application of Acoustic-Electric Imaging Data to Evaluation of Fractures in Carbonate Reservoir ZHANG Hui, XIAO Cheng-wen, HAI Chuan 2009, 30 (2):  252-254.  Abstract ( 89 )   PDF (460KB) ( 255 )   Save In view of relation between effective fractures and principal stress, the principle and the method for determination of fracture effectiveness of carbonate rocks using acoustic-electric imaging well logs are presented. The case study from fractured carbonate reservoir in Tazhong area of Tarim basin shows that the acoustic-electric imaging data can be effectively used for proper determination of fractures in carbonate rocks. References | Related Articles | Metrics

Seismic Acquisition Techniques in Thick Loess Area in Southwest Depression, Tarim Basin LIU Yi-mou, LIANG Xiang-hao, SUN Jian-hua, ZHANG Xin-dong, LUO Wei-dong 2009, 30 (2):  255-257.  Abstract ( 81 )   PDF (501KB) ( 255 )   Save The thick loess area in southwest depression of Tarim basin is always one of the most complex regions for seismic survey. Being covered with thick loess, the shooting and receiving conditions are poor, resulting in severe absorption and attenuation of seismic waves as well as low signal-to-noise ratio. In order to find out Kexi-2 structure found by non-seismic prospecting, such 2D seismic acquisition techniques as array shooting, long geophone array receiving and wide-line acquisition ones are all applied in this area. The results show that the seismic profile acquired is of much higher quality than ever before, proving these techniques are effective and practicable. References | Related Articles | Metrics

Ascertainment of Complex Cliffy Structural Traps— An example from Keshen No.2 structure WANG Xing-jun, PENG Geng-xin, MAN Yi-zhi, ZHANG Yao-tang, LAI Jing-rong, LUO Ping 2009, 30 (2):  258-260.  Abstract ( 95 )   PDF (209KB) ( 215 )   Save The complexity of surface and subsurface structures makes Kuqa complex and cliffy structural trap be difficultly ascertained. Since 2005, the stress has been placed on study of complex mountainous seismic exploration technique, especially related seismic acquisition and fine velocity modeling techniques, and finally establishing a systematic method for ascertaining complex cliffy structural traps. This paper presents the method, including the seismic acquisition technique for ascertaining structural style, the superficial velocity inversion modeling technique, T0 drift correction technique and variable velocity mapping technique, for determination of cliffy structural traps. Also, the prestack depth migration outcome at the main part of structure is used to make a correlation and validation for the purpose of improving the precision of ascertaining the complex cliffy structural traps. The application of this method to complex mountains in Tarim basin receives good effectiveness. References | Related Articles | Metrics

Acoustic Impedance Inversion Based on Wavelet Edge Analysis and Modeling CUI Yong-fu, PENG Geng-xin, LI Guo-hui, XIANG Dong, LUO Li-li, ZHANG Hong-xia 2009, 30 (2):  261-263.  Abstract ( 67 )   PDF (423KB) ( 244 )   Save The acoustic impedance inversion based on wavelet edge analysis modeling (AIW) can take both well-logging acoustic impedance and seismic attributes from seismic data as restrictions to build initial inversion model, thus avoiding bad influence brought by inaccurate initial model due when using conventional inversion methods and improving accuracy of inversion. The results show higher resolution and well match with the well data. References | Related Articles | Metrics

Seismic Technique and Application of Volcanic Rock Facies YU Bao-li, LIU Xin-li, FAN Su-fang, LIU Hong, WANG Ke-ming 2009, 30 (2):  264-266.  Abstract ( 90 )   PDF (545KB) ( 264 )   Save In recent years, with the continuous discovery of volcanic reservoirs, the reserves are more and more becoming new points of incremental reserves. However, as a kind of special reservoir, the volcanic reservoir is still difficult in study and in prediction. Taking the Carboniferous volcanic rocks in Wucaiwan area of Junggar basin as an example, the identification model for volcanic facies is developed, the seismic study method for it is presented and the favorable zones for volcanic reservoir prospecting are predicted, based on available volcanic lithology and lithologic assemblages as well as corresponding seismic responses, which provide a assistant and practicable method for prediction of volcanic facies in this and similar areas. References | Related Articles | Metrics

Application of Stress Variation Analysis to Prediction of Buried-Hill Fracture of Ordovician in Lunnan Area GUAN Wen-sheng, TAN Lin, LI Guo-hui, ZHANG Yao-tang, ZENG Li-ping, WAN Xiao-guo 2009, 30 (2):  267-268.  Abstract ( 61 )   PDF (239KB) ( 189 )   Save 3D MOVE and 3D STRESS models are used to analyze the fault, fracture shape and distribution of buried hill of carbonate rocks in Lunnan area, including the stress mechanism, stability and slip vector of fault faces, the extension tendency, slip tendency and factors of seepage and leakage of fracture and fault faces. The reservoirs controlled by the fault and fractures are predicted, and the connection and stability of fractures are analyzed, in order to effectively guide exploration and development in the studied area. References | Related Articles | Metrics

Application of CT Scanning Image Technique to Study of Oil Saturation Distribution in Core Displacement Test GAO Jian, HAN Dong, WANG Jia-lu, WU Kang-yun, LIU Li 2009, 30 (2):  269-271.  Abstract ( 153 )   PDF (318KB) ( 501 )   Save With CT technique, oil saturation distribution can be measured. Original oil saturation and residual oil saturation of different sections and orthogonal intersections as well as 3-D oil saturation can be determined by core scanning in three states which are dry, saturated with formation water and oil displaced by water, thus realizing the visualization and quantitative characterization of oil saturation distribution in core water flooding experiment. The heterogeneity of core oil saturation distribution can be evaluated with standard deviation and variation coefficient. The difference between the CT value and real oil saturation is less than 3%, indicating that the result of CT technique is more accurate than those of other methods for description of the distribution and variation of oil saturation in core displacement test. References | Related Articles | Metrics

Deep Crustal Structure and Hydrocarbon Accumulation in Ordos Basin ZHANG Jing-lian, SHI Lan-ting, WEI Ping-sheng, ZHANG Hu-quan, CHEN Qi-lin, LI Yang-jian 2009, 30 (2):  272-278.  Abstract ( 120 )   PDF (537KB) ( 498 )   Save Based on the basement feature, basement faults distribution, thick dolomite occurrence, existence of gypsum-salt (especially sylvite) and abundant metal hydrothermal minerals in Ordos basin, it is indicated that there once existed intensive action of mantle fluid in this basin. The study of the deep crustal structure of Ordos basin and the western basins (Yinchuan basin and Liupanshan basin) shows that no mid-crust low velocity layer occurs in deep Ordos basin, but low velocity and high conductive layers widely appears in mid-crust of Yinchuan basin and Liupanshan basin, in which natural gas is generated from the Mantle fluid by Fischer-Tropsch synthesis in Yinchuan basin, while crude oil from it in Liupanshan basin. It is the tectonic compression nappe actions of Late Mesozoic that, on one hand, allow the natural gas in Yinchuan basin to migrate from west to east along unconformity (dominated by weathering crust) between the Ordovician and the Carboniferous (Permian) and structural fractural system and shape poors; on the other hand, allow the crude oil in Liupanshan basin to migrate toward the same direction along pseudoconformity between the Triassic and the Jurassic and form reservoirs. Also, Rujigou coal mine with low sulfur, low ash and premium anthracite is originated partly from the carbon-enriched mantle fluid in Yinchuan basin. the distribution pattern of rare-earth elements of Mesozoic petroleum pitch and the carbon and hydrogen isotope features of Paleozoic natural gas indicate the participation of such a deep crust mantle fluid. According to these, the reefs (dolomite as reservoir, gypsum-salt as cap rock) of Lower Paleozoic in Ordos basin are the main targets for further petroleum exploration; in deep Dongsheng area of Yimeng uplift in northern Ordos basin there exist mid-crust low velocity and high conductive layers, so large oil-gas field could be found below Dongsheng sandstone uranium deposit. At present, in Mid-Proterozoic of Yimeng uplift encountered natural gas by drilling (Jin-13 Well) and ignited successfully, foreshowing that there are bright prospects for petroleum exploration in basement rocks in northern Ordos basin. References | Related Articles | Metrics