Table of Content

01 August 2007, Volume 28 Issue 4 Previous Issue    Next Issue

For Selected:

Download Citations EndNote Reference Manager ProCite BibTeX RefWorks

Toggle Thumbnails

Research on Cracking Principles of Brittle Low-Permeability Sands DAI Jun-sheng, WANG Bi-feng, MA Zhan-rong 2007, 28 (4):  393-395.  Abstract ( 104 )   PDF (168KB) ( 463 )   Save In the quantitative research on fracture, some principles for rock fracture are usually adopted to confirm when and in which direction the rock fractures occur under stress. Usually, tectonic fracture appears in several forms such as tension fracture, conjugate shear fracture and tension-shear fracture. It is necessary to comprehensively apply the tension fracture principle and the shear fracture principle in case studies. On the basis of Coulumb-Mohr and Griffith fracture principles, this paper puts forward rock-cracking examination principle for low-permeability sand reservoir in combination with the results of rock mechanical test, in which Griffith principle is applied to tension fracture examination, while Coulumb-Mohr principle to shear fracture examination. References | Related Articles | Metrics

Application of Frequency Attribute Analysis to Identification of Conglomerate Body—An example of Wu-27 Wellblock in Wu-Xia faultbelt YUE You-xi, ZHANG Jun-duo, LIU Zhen-yu, GUO Xu-guang 2007, 28 (4):  396-398.  Abstract ( 89 )   PDF (280KB) ( 196 )   Save There exists a set of thick conglomerate body in Xiazijie formation of Permian in Wuerhe area in Wu-Xia fault belt, and highyield oil zone was found at the top of it. However, it is not obvious differences in seismic reflection between the conglomerate and underlying strata, which allow the identification and tracing to be difficult. This paper presents in-depth research on that by frequency attribute analysis and finds out the reflected differences. By 3D seismic data process, the conglomerate feature is confirmed, and its plane distribution is outlined. The results show a coincidence with the well data. References | Related Articles | Metrics

Characteristics of Structural Migration in Wu-Xia Fault Belt, Junggar Basin LIU Zhen-yu, XU Huai-bao, PANG Lei 2007, 28 (4):  399-402.  Abstract ( 101 )   PDF (261KB) ( 386 )   Save A large number of reverse growth faults occur in Wu-Xia fault belt of Junggar basin. This paper presents the analysis of the growth index of fault and the combination relations among faults and gives five types of lateral combinations of the faults like parallel, en echelon, oblique, orthogonal and brush ones. The study shows that in Permian, the faults mainly grew and distributed along NE direction, during Triassic and Jurassic, they distributed in crosscutting and superimposing and arc-like appearance along EW trend. The faults activities are characterized by subsection in space and segmentation in time, at the early time the faults activities were stronger in the west than in the east, however, at the late time things were opposite; from Permian to Jurassic the center of fault activities migrated from west to east, with gradually weakening of intensity. References | Related Articles | Metrics

Fault Activities and Hydrocarbon Accumulation in Wu-Xia Fault Belt in Northwestern Margin of Junggar Basin QU Jiang-xiu, QIU Yi-bo, SHI Zhen-feng, GAO Wei-hong 2007, 28 (4):  403-405.  Abstract ( 93 )   PDF (195KB) ( 189 )   Save Wu-Xia fault belt is located in the eastern part of thrust zone in northwestern margin of Junggar basin, which was tectonically the most active area here. The multistage tectonic activities allowed the lateral and vertical styles of the fault belt to be of complexity and diversity. It is vertically divided into the deep fault system and the shallow fault system bounded by the bottom of Jurassic. Because of differences in active period and intensity of the fault, the deep and shallow fault systems showed obvious differences in controlling the hydrocarbon accumulation. The Triassic-Jurassic fault active period matched well with the hydrocarbon generation and expulsion periods and had an important effect on hydrocarbon migration and accumulation. The active faults and the unconformities form the Z-like transportation networks, resulting in stepped hydrocarbon migration and accumulation from deep strata to shallow strata and from sag centers to basin margins in this region. References | Related Articles | Metrics

Tectonic Units in Wu-Xia Fault Belt, Junggar Basin FENG Jian-wei, DAI Jun-sheng, LIU Wei, WANG Jun, LI Ming 2007, 28 (4):  406-409.  Abstract ( 121 )   PDF (341KB) ( 218 )   Save The Wu-Xia fault belt of Junggar basin is divided into eight second-order tectonic units based on the study on tectonic features and tectonic evolution, such as Wuerhe thrust belt, Wuerhe fault-fold belt, Wuerhe monocline belt, Wuerhe-Xiazijie thrust belt, Wuerhe-Xiazijie monocline belt, Xiazijie-Hongqiba thrust belt, Xiazijie-Hongqiba fault-fold belt and Xiazijie-Hongqiba monocline belt, which reflect the characteristics of structural segmentation in east-west direction and structural zonation in south-north direction. According to the development of structural traps and the conditions of hydrocarbon accumulation, these second-order tectonic units are studied in hydrocarbon accumulation type and distribution. It is concluded that the fault-fold types in this area are most developed and serve as major oil production areas; the monocline belts are of the greatest explorative potentials, being the favorable prospecting areas. References | Related Articles | Metrics

Characteristics and Origin of Structural Accommodation Zone in Wu-Xia Area, Junggar Basin XU Duo-nian, WANG Wei-feng, QIU Yi-bo, XIN Ye, GUO Jian-gang 2007, 28 (4):  410-412.  Abstract ( 109 )   PDF (170KB) ( 183 )   Save Structural accommodation zones are usually studied in extensional basins in eastern China, but less studied in compressional basins in western China. In this paper, the accommodation zone in Wu-Xia area in Junggar basin is divided into three types such as synthetic approaching type found in Xiazijie area, synthetic overlapping type in Wuerhe area and synthetic collinear type in transitional zones of Wuerhe, Wu-Xia and Xia-Hong areas. The sand distribution could be controlled by accommodation zone, and its adjacent faults may serve as channels for oil-gas migration, so the accommodation zone is a favorable place for oil-gas migration and accumulation. The study shows that the accommodation zones between Baiwu fault and Wunan fault, Xia-59 Well fault and Xiahongnan fault, Wuerhe fault and Wu-Xia fault, as well as between Wu-Xia fault and Xiahong fault should be favorable areas for forming oil-gas reservoirs. References | Related Articles | Metrics

Geochemical Feature of Natural Gas in Wu-Xia Area, Junggar Basin LI Xiu-peng, ZHA Ming, WU Kong-you 2007, 28 (4):  413-415.  Abstract ( 95 )   PDF (158KB) ( 267 )   Save The natural gas in Wu-Xia area is dominated by methane wet gas of high maturity with dry coefficient of 0.8801, V(iC4)/V(nC4) of 0.88, V(iC5)/V(nC5) of 0.99 in average. Its non-hydrocarbon gas contains high content of N2, less CO2, micro-O2 and free H2S. With increase of the depth, the relative density, dry coefficient, methane content, heavy hydrocarbon gas content and non-hydrocarbon gas content have 7 changing trends by regularity. The natural gas is characterized by δ13C1<δ13C2<δ13C3<δ13C4 and the alkane gas is original organic genetic gas. The source rocks produce gases in low-matured and matured stages with Ro from 0.21% to 1.66%. According to the relationship between δ13C1 and δ13C2-δ13C1 as well as δ13C1 vs. V(C1)/V(C2+3), it is judged that the origin of natural gas belongs to associated gas of crude oil, and a small amount of associated gas of condensate oil may occur in Wu-32 Wellblock. References | Related Articles | Metrics

Prediction of Deep Volcanic Rocks in Wu-Xia Fault Belt by Seismic Attributes GAO Lei, WANG Yong-gang, ZHANG Ke, LIU Zhen-yu, HUANG Li-liang 2007, 28 (4):  416-418.  Abstract ( 84 )   PDF (201KB) ( 251 )   Save The deep reservoir (Permian) of Wu-Xia fault belt in Junggar basin is characterized by the deep buried, developed faults, random seismic reflection and complex structures, etc. These make the prediction of the deep reservoir more difficult. The drilling data show that the developed volcanic reservoirs of Permian serve as the favorable zone for hydrocarbon accumulation. This paper presents the geologic and geophysical features of the volcanic rocks in Wu-Xia fault belt and their fine horizon calibration and interpretation, based on which several seismic attributes are picked up along the horizons, of which three attributes are selected such as average absolute amplitude, arc length and energy gradient at half (life) period. And the comprehensive classification given by means of Kohonen neural network is put forward, by which the lateral prediction of the volcanic reservoirs in Fengcheng formation of Permian is conducted and the next drilling well sites are determined, considering previous drilling, geologic and geophysical research results. The study shows that the seismic attributes are of good effects on the deep volcanic reservoir predictions. References | Related Articles | Metrics

Application of Kohonen Neural Network to Deep Sedimentary Facies Division in Wu-Xia Area, Junggar Basin ZHANG Ke, WANG Yong-gang, YUE You-xi, GUO Wen-jian, ZHANG Ji-hui, GAO Lei 2007, 28 (4):  419-421.  Abstract ( 73 )   PDF (207KB) ( 200 )   Save The 3D seismic data-processing assembly with the merit of high signal-to-noise ratio and the obvious wave characteristic is used to select high-reliability seismic reflection internal texture and external shape from Xiazijie formation of Permian in Wu-Xia area of Junggar basin. By means of such seismic attributes as instantaneous amplitude, instantaneous frequency and persistence length, the seismic facies is quantitatively analyzed and nominated using Kohonen neural network method. The results from well log interpretation, core analysis and palaeontologic evidence are applied to conversion of the seismic facies into sedimentary facies, thus well solving the problem unable to classify the sedimentary facies with few deep well in the past. References | Related Articles | Metrics

Fracture Characteristic of Permian Volcanic Reservoir in Wu-Xia Area, Junggar Basin LI Ming, DAI Jun-sheng, FENG Jian-wei, WANG Jun 2007, 28 (4):  422-424.  Abstract ( 79 )   PDF (207KB) ( 234 )   Save There are developed fractures or fissures in the Permian volcanic reservoirs in Wu-Xia area, which control the reservoirs' distribution as important channels for hydrocarbon flowing and storage. In view of the volcanic reservoir distribution and structural feature, this paper presents the research and analysis of the fracture characteristic of the volcanic rocks and the identification of structural fracture by means of rock observation and image logging. The results show that this method can be used to precisely determine the fracture parameters, calculate fracture porosity and evaluate the volcanic reservoir. References | Related Articles | Metrics

Sedimentary Facies of Triassic in Wu-Xia Fault Belt, Junggar Basin NIU Hai-qing, CHEN Shi-yue, YAN Ji-hua, JIANG Zu-qiang 2007, 28 (4):  425-427.  Abstract ( 94 )   PDF (243KB) ( 235 )   Save Through core analysis, well logging, borehole log and seismic data, the sedimentary facies feature and depositional system of Triassic in Wu-Xia fault belt of Junggar basin is systematically studied. The result shows that four types of sedimentary facies occur in this area, they are alluvial fan, fan delta, sublacustrine fan and lake facies. The Baikouquan formation to Baijiantan formation here experienced arid-wet changing climate in lake transgressive process. Baikouquan formation is characterized by alluvial fan groups of Xiazijie and Baikouquan areas; Upper and Lower Karamay formation by fan delta and shore-lake sediment; Baijiantan formation as a largest laketransgressional episode dominated by lacustrine fan sediment with small scale fan delta and sublacustrine fan sediments. It is concluded that the fan delta front of Karamay formation is the most favorable sedimentary facies with best reservoir property; the midfan of Baikouquan alluvial fan fitted with the faults and unconformities could also be good prospecting areas for hydrocarbon accumulation. References | Related Articles | Metrics

Diagenesis and Porosity Evolution of Jurassic Reservoir in Wu-Xia Area, Junggar Basin XUE Xin-ke, HUANG Zhi-jiu, LI Zhen-hua, GUO Jian-gang 2007, 28 (4):  428-431.  Abstract ( 107 )   PDF (286KB) ( 315 )   Save The Jurassi reservoir in Wu-Xia area is dominated by lithic sandstone and feldspathic litharenite under alluvial fan, fan delta and braided river sedimentary environments. The diagenesis study shows that the porosity evolution of reservoir is closely related with the diagenesis types. Compaction and early cementation are the main reasons for destroying primary pores. The dissolution of detrital grain, clay mineral and calcite is the main factor for forming secondary pores. And the cement like ferrocalcite is responsible for the destruction of the secondary pores. The porosity evolution experienced three steps, including the destroying of primary pores, formation of secondary pores and destruction of secondary pores. References | Related Articles | Metrics

Identification of Sand Body of Triassic in A67 Wellblock of Xiazijie Area, Junggar Basin LI Zhen-hua, LIU Quan-yan, LIU Guo-liang, HUANG Zhi-jiu, HUANG Li-liang 2007, 28 (4):  432-433.  Abstract ( 117 )   PDF (169KB) ( 211 )   Save With the continuous petroleum exploration in Junggar basin, lithologic trap's exploration becomes the focal point of work in the days to come. How to make an identification, prediction and description of the lithologic traps is a problem to be urgently solved. This paper presents the studies of A67 Wellblock in Xiazijie area as a target zone using sequence stratigraphy theory, integrated with the drilling data and sedimentary facies analysis, including formation correlation, layer division, sand body selection, seismic attribute extraction and seismic facies identification, etc. The study indicates that there exist several sand bodies in Lower Karamay formation of A67 Wellblock. This provides an effective method for identification of the lithologic traps in this area. References | Related Articles | Metrics

The Key Factor of Jurassic Hydrocarbon Accumulation in Wu-Xia Fault Belt, Junggar Basin WU Kong-you, HONG Mei, NIE Zhen-rong, ZHANG Li-gang, ZHENG Zhi-xiang 2007, 28 (4):  434-436.  Abstract ( 85 )   PDF (162KB) ( 419 )   Save Wu-Xia fault belt is a large-scale overthrust belt developed from Late Carboniferous to Triassic and faults mostly develop below the Triassic. The structure overlying the Jurassic occurs mainly in monocline. Oil-gas reservoirs have been found in the Permian, the Triassic and the Jurassic, of which the oil-bearing horizons of Jurassic are mainly found in its Badaowan formation, dominated by stratigraphic and lithologic oil-gas reservoirs, with strong secondary reconstruction of crude oil. The dissection of the Jurassic typical reservoirs in this area indicates that the oil and gas migrated along the faults to the basal unconformity of Jurassic followed by starting lateral migration, and accumulation in the basal conglomerate or the transgressed sand bodies due to meeting barrier beds of updip heavy oils. Such an idea has been examined from exploration and practices. References | Related Articles | Metrics

Sequence Division and Stratigraphic Evolution of Jurassic in Wu-Xia Area, Junggar Basin YANG Huai-yu, CHEN Shi-yue, YANG Jun-sheng, WU Cai-xi 2007, 28 (4):  437-440.  Abstract ( 103 )   PDF (372KB) ( 225 )   Save This paper presents the sequence division scheme of Jurassic in Wu-Xia area in northwestern margin of Junggar basin by means of logging-seismic data analysis and well-connecting framework sequence analysis, through the seismic, drilling and well log data to find out the identification marks of the sequence boundaries. The result shows that the Jurassic system could be divided into two supersequences and seven sequences. The first super-sequence includes JSQ1, JSQ2, JSQ3, JSQ4 and JSQ5, corresponding to the Badaowan and Sangonghe formations of Lower Jurassic and the Xishanyao formation of Middle Jurassic. The second super-sequence includes JSQ6 and JSQ7, corresponding to the Toutunhe formation of Middle Jurassic and the Qigu formation of Upper Jurassic. All the sequences occur in a cycle of early retrogradation and late progradation in plane. The strata characteristics are resulted from combination of sedimentary formation and reformation. References | Related Articles | Metrics

Application of Log Facies Analysis to Lithologic Reservoir Exploration—An example of Triassic in Wu-Xia area WANG Xiao-jun, CHEN Gang-hua, YU Jie, LIU Wei, YU Chun-hui 2007, 28 (4):  441-443.  Abstract ( 96 )   PDF (186KB) ( 194 )   Save This paper presents the basic principle and procedure for reconstruction of stratigraphic lithology and sedimentary microfacies using log facies analysis technique, and discusses the thought for analysis of high-resolution sequence stratigraphy, prediction and optimization of lithologic traps in possible area as well as determination of best prospecting targets based on well log data. Hence a model for quantitative interpretation of lithology and depositional microfacies of Triassic strata in Wu-Xia area of Junggar basin is developed and verified effectively. References | Related Articles | Metrics

A Study on Biodegradation of Heavy Oil in Wu-Xia Area, Junggar Basin MAO Xin-jun, HUANG Li-liang, FAN Xiang-dong 2007, 28 (4):  444-447.  Abstract ( 104 )   PDF (244KB) ( 216 )   Save The heavy oil mainly distributes in Fengcheng oilfield of Wuerhe-Xiazijie area in Junggar basin. Affected by the biodegradation, the density and viscosity of heavy oil are very high, normal paraffin hydrocarbons and pentacyclic isoprenoid paraffin hydrocarbons are subjected to serious degradation, so are partial hopanes, steranes and homosteranes, and free carotene, while tricyclic terpanes, pregnanes and homopregnanes are in high content, with high Ts/Tm value of 3.55. This paper presents the six ranks of biodegradations of heavy oils in Wu-Xia area, and accordingly gives six types of heavy oils in this area, based on the degradations of normal-and iso-alkanes, biomarkers and 25-norhopanes as well as the contents of tricyclic terpanes and pregnanes. References | Related Articles | Metrics

Characteristic of Tectonite in Paleozoic-Archean Decollement Structural Belt in Luxi Area LI Li 2007, 28 (4):  448-452.  Abstract ( 87 )   PDF (453KB) ( 269 )   Save The macro-and micro-feature of tectonite of Paleozoic-Archean decollement structural belt in Luxi (West Shandong) area is presented by means of structural geology, field geologic survey and lab microstructure analysis, including its effect on deep hydrocarbon exploration. The outcrop study shows that the tectonite is consisted of cataclastic rock with rubbles of carbonate rock, associated with dynamic metamorphisms of silification, marblezation, specularitization and chloritization. Crumpled structure is developed in the thin tectonite. The microstructures of calcite, spar and quartz show the microfeatures of gliding twins, mechanic twins and dynamic recrystallization, indicating that the structural deformation is brittle and plastic deformation with a low temperature. The tectonite of Paleozoic in areal coverage appears the similar characteristic with that in outcrop area, and its cataclastic structure serves as an effective space for oil-gas accumulation. The study shows that the unconformity between the Paleozoic and the Archean was reformed into a structural decollement surface, being of a great significance to the exploration and development of deep buried-hill petroleum reservoirs in this area. References | Related Articles | Metrics

Characteristics of Coal-Formed Gas Reservoir of Permian in Gubei Area WANG Feng-hua, TAN Bin-tian, LIU Fang, ZHANG Guan-long, CHEN Shi-yue 2007, 28 (4):  453-456.  Abstract ( 88 )   PDF (247KB) ( 209 )   Save The Carboniferous-Permian in Gubei area is relatively less eroded away compared to other areas in Jiyang exploration area, which has favorable self-generating and self-reserving coal-formed conditions. The Permian reservoir rock is dominated by gritstone and pebbled gritstone with quarter minerals. The storage space of reservoir occurs in primary intergranular pore, secondary pore, intercrystal micro-pore and fracture, dominated by secondary pore and fracture, belonging to low-porosity and low-permeability reservoir. The Upper Shihezi formation is of the best reservoir quality, while the Shanxi formation is of the poorest one of the Permian. And sedimentation, diagenesis and tectonization are the three factors controlling the reservoir quality, of which tectonization is the main controlling factor. The Permian reservoir in Gubei area is divided into four types for evaluation. The results indicate that the Upper Shihezi and the Lower Shihezi reservoirs belong to high-quality ones of type I and type II, and Gu-3 Wellblock in Gubei area is a central area for petroleum reservoir. References | Related Articles | Metrics

Depositional System of the Third Member of Shahejie Formation of Paleogene in Huimin Sag YANG Jun-sheng, FAN Tai-liang 2007, 28 (4):  457-461.  Abstract ( 100 )   PDF (398KB) ( 426 )   Save The third member of Shahejie formation of Paleogene (Es3) in Huimin sag of Shandong province is divided into three middle base level cycles and one base level rising semi-cycle, which includes six types of sedimentary facies such as delta, fan delta, turbidite fan, turbidite channel, slump turbidite and lacustrine facies. These sedimentary facies could be assembled into such five depositional systems as fluvial-delta system, delta-(slump) turbidite system, fan delta system, fan delta-slump turbidite system and near-shore submarine fan system. Taking the middle base level cycle (C3) as an example, the horizontal distributions of these depositional systems are analyzed. References | Related Articles | Metrics

A Study on Volcanic Reservoir Fracture of Fu-2 Member of Paleogene in Min-4 Fault Block in Minqiao Oilfield ZHANG Jian-liang, ZHOU Fang-xi 2007, 28 (4):  462-464.  Abstract ( 87 )   PDF (181KB) ( 161 )   Save The fractural parameters of volcanic reservoir of Fu-2 Member of Paleogene in Min-4 fault block in Minqiao oilfield are predicted using tectonic stress field numerical simulation integrated with core fissure description. The study shows that lots of fractures occurred due to intense tectonic movement in Late Funing period, which were mainly distributing near the faults with trend of NEE. The present stress has modified effect on these fractures. The values of present fracture aperture, density, porosity and permeability are less than those of paleo-fractures, and the values of fracture parameters within the fault block are less than those of them near the faults. References | Related Articles | Metrics

Sequence Stratigraphy and Sedimentary Response of Fault-Depression Transform Period in Zhanhua Sag YAN Ji-hua, ZHANG Peng, CHEN Shi-yue, ZHANG Ming-jun 2007, 28 (4):  465-467.  Abstract ( 110 )   PDF (227KB) ( 193 )   Save The upper Sha'er-Dongying formation of Paleogene in Zhanhua sag is in period of fault-depression transform. The comprehensive analysis indicates that the formation could be divided into three long-term cycles and six middle-term cycles, in which nine sedimentary facies are developed such as alluvial fan, river, delta, braided river delta, fan delta, shallow lake, beach bar, semi-deep lake and deep lake and sublacustrine fan. The favorable reservoir sand bodies mainly distribute in C1, C2 and C4 cycles. The distributions of sedimentary systems are influenced by basal settlement, fault activity, provenance and paleoclimate, etc. References | Related Articles | Metrics

Characteristics and Evaluation of Reservoir of Upper Es2 of Paleogene in Zhanhua Sag ZHANG Peng-fei, CHEN Shi-yue, ZHANG Ming-jun, YAN Ji-hua 2007, 28 (4):  468-470.  Abstract ( 85 )   PDF (230KB) ( 151 )   Save Through systematical analysis of data of drilling, well-logging, thin-section and cast-section in 84 wells, the distribution and characteristics of the sandstone reservoir of upper Es2 of Paleogene in Zhanhua sag are studied in detail. The reservoir is characterized by the micro-facies sands of both fan delta frontal sub-aqueous distributary channel and beach bar of littoral and shallow lake, with lithology of lithoclasitic quartz sandstone and lithic sandstone, and dominated by primary pores of 8%～24% and permeability of (1～100)×10-3μm2. According to the characteristics of porosity, permeability, pore configuration, pore combination and petrological structure, the reservoir is classified into three types of I, II and III. Type I is high-quality reservoir distributing in the southeastern Zhanhua sag; type II is medianquality one which lies in the eastern and northern Zhanhua sag, while type III is poor one in the northwestern Zhanhua sag, the west of Kendong swell and the south of Gudao swell. References | Related Articles | Metrics

Present Ground Stress in Dina Gas Field WANG Bi-feng, DAI Jun-sheng, CHENG Rong-hong, YAN Ping, WANG Yun-he 2007, 28 (4):  471-472.  Abstract ( 108 )   PDF (208KB) ( 405 )   Save Based on key well log data and rock mechanics experiment, the present ground stress distribution of Paleogene reservoir in Dina gas field is predicted with finite element method. The result shows that the present principle stress here assumes compressive stress with the maximum horizontal stress orientation being NNE10°, the maximum value about 109.56 MPa and the minimum value about 106 MPa, and the vertical stress value averaging about 115 MPa. References | Related Articles | Metrics

Evaluation of Source Rocks in Minfeng Sub-Sag, Dongying Sag XIN Ye, WANG Wei-feng 2007, 28 (4):  473-475.  Abstract ( 113 )   PDF (215KB) ( 194 )   Save As a foundation of composite geologic assessment, the quantitative evaluation of source rocks in Minfeng sub-sag is made using well logging method in this paper, then the effective source rock is identified, and generation and expulsion amounts of hydrocarbons in Yongbei area are estimated. This provides a significant basis for hydrocarbon accumulation study here. References | Related Articles | Metrics

Structural Evolution of South Terrace in Gaoyou Sag MA Xiao-ming, DAI Jun-sheng 2007, 28 (4):  476-479.  Abstract ( 83 )   PDF (275KB) ( 238 )   Save The south terrace in Gaoyou sag is presented, according to the analysis of the structural evolution section. That is, when the Sanduo movement ended, the south terrance activity tended towards calming down, and all faults in it stopped acting, accordingly, hence forming present structural framework. Once shaping a good match between the fault-active period and hydrocarbon-migrating period, could the faults become major channels for vertical migration of hydrocarbons and lateral crosscutting followed by forming favorable hydrocarbon traps in Gaoyou sag. References | Related Articles | Metrics

Fault Activities and Their Controls on Depositional Sequences in Minfeng Sub-Sag CHEN Gang-qiang, WANG Wei-feng, WAN Jun 2007, 28 (4):  480-482.  Abstract ( 86 )   PDF (158KB) ( 322 )   Save Two sets of fault systems are found in Minfeng sub-sag. One is Chennan fault in the north, and the other is Minfeng fault belt in the middle. This paper studies these two faults by covering their original depositional thickness from formation de-compaction correction, followed by calculating the fault throw and the growth index of these two faults in different periods. The study shows the faults activities: for Chennan fault, it was active strongly from the early Es3 to the middle Es3, and active lightly from the late Es3 to the Es2; for Minfeng fault, it was not formed during the early and middle Es3 until the late Es3. Such differences of the fault activity resulted in strata thickness of the lower and middle Es3 in Minfeng sub-sag assuming wedge shape with the thick in the north and the thin in the south, while the upper Es3 to the Es2 assuming thin in north and thick in south. These features indicate it is the faults activities that control the development of depositional sequence in this area. References | Related Articles | Metrics

Prediction of Fracture Parameter in Low Permeability Sandstone Reservoir of Fu-2 Member of Paleogene in Shigang Oilfield JI Zong-zhen, DOU Zhi-lin, XIE Qiu-hong, MA Xiao-ming 2007, 28 (4):  483-485.  Abstract ( 83 )   PDF (175KB) ( 201 )   Save Rock burst and structural fracture are influenced and controlled mainly by tectonic stress field. On the basis of stress field numerical simulation and rock fracture rules, the fracture parameters of Fu-2 member reservoir of Paleogene in Shigang oilfield are predicted. The study shows that the fractures occurred under the paleo-stress field in late Funing episode, and were mainly distributed near the Shigang fault. The present stress field is of modified effect on the fractures, allowing the high values of fracture aperture, fracture density, porosity and permeability to appear in the northwestern Shi 3-Shi 6 fault block and Shi 4 fault block, the northern Jin 4 fault block and the middle and southern Shi 11-Shi 5 fault block. References | Related Articles | Metrics

Control of Faults of Guantao Formation on Hydrocarbon Accumulation in Jiyang Depression XIE Qiu-hong, DAI Jun-sheng, MA Xiao-ming 2007, 28 (4):  486-489.  Abstract ( 86 )   PDF (311KB) ( 231 )   Save This paper presents the quantitative analysis of fault activity intensity and regularity of Guantao formation and the systematic study of its effect on controlling the hydrocarbon accumulation. The results show that the inherited major fault and the sub-fault of Guantao formation served as the main channels for vertical hydrocarbon migration; the fault activity controlled the vertical and horizontal distribution through its control to vertical hydrocarbon migration; the active stage and intensity of the major fault and the sub-fault determined the difference between the vertical and the horizontal distributions of oil-gas reservoirs in Guantao stage. It is predicted that the main areas for petroleum prospecting in Jiyang depression could be at Zhanhua sag and beach area. References | Related Articles | Metrics

Physical Modeling of Extensional Structures Since Late Mesozoic in Luxi Uplift SHI Xiu-peng, LI Li 2007, 28 (4):  490-493.  Abstract ( 100 )   PDF (306KB) ( 235 )   Save The extensional structures like normal fault since late Mesozoic in Luxi (west Shandong) are mostly formed by negative reverses from the Mesozoic thrust faults. They have both inherited early structural features and appear new active characteristics under new tectonic stress field. Therefore, they are normally characterized by multi-phase and multi-direction and complex styles in structural activity. This paper presents the physical modeling of the complex extensional structures and their evolution histories since late Mesozoic in Luxi uplift using analogy theory. The quantitative and semi-quantitative experiments show that the structural patterns since late Mesozoic in Luxi uplift appear the steep-flat alternative tilted blocks, and undergo three extensional periods of late Cretaceous, Paleocene and Eocene. Also, the flat faults occur somewhat later than the steep faults. Mechanically, the extensional structures are controlled by NESW extension and vertical magma upwelling. References | Related Articles | Metrics

Compound Attribute as New Method for Pickup and Interpretation of Seismic Attributes ZHANG Jun-hua, ZHU Huan, GAO Rong-tao, ZHOU Zhen-xiao 2007, 28 (4):  494-496.  Abstract ( 109 )   PDF (410KB) ( 632 )   Save The technologies for pickup of seismic attributes include generally Fourier spectral analysis, autocorrelation, main component, autoregression and coherent body, etc. However, how to get new seismic attributes from the extracted attributes is still insufficiently concerned about. This paper proposes a new seismic attribute-compound attribute and develops the corresponding software package by means of information engineering principle, which is characterized by simple physical significances such as overlay, difference, product and cascade, etc. and sensitive data match and display. The compound attribute is used for the detailed interpretation of fluvial facies reservoir in LHK area, showing that the resolution and the S/N ratio are improved obviously. References | Related Articles | Metrics

Synthetic Seismogram in Angle Domain SONG Jian-guo, WANG Yan-xiang 2007, 28 (4):  497-499.  Abstract ( 84 )   PDF (191KB) ( 207 )   Save Seismic synthetic record in common angle domain is different from conventional one. When incident angle is greater than critical angle, reflection coefficient becomes complex number. To calculated the modulus of reflection coefficient and to make synthetic seismogram in time domain do not present the phase message of waveform. This paper calculates the reflection coefficient using approximate formula derived from Zoeppritz equation for any incident angle. Using Fourier transform, big angle seismic record with complex coefficient is modeled in frequency domain. Using given treatment scheme, synthetic seismogram is modeled in angle domain. This provides basic data for the study of waveform deformation correction method in cross-well seismic data processing. References | Related Articles | Metrics

Prediction of Reservoir Porosity in Wuerhe Field of Junggar Basin Using Seismic Attributes HE Zhou, CHEN Yong-jun, GUO Wen-jian 2007, 28 (4):  500-503.  Abstract ( 92 )   PDF (281KB) ( 319 )   Save The seismic attributes of 43 types are extracted from Wuerhe Wellblock seismic data, of which 5 are selected as basic parameters of the reservoir porosity prediction model using clustering analysis. And the porosities at wells available are used to make a prediction of the reservoir parameters of target zone by multiple regression and nonparametric regression. The results show good effect for its application to the target zone. References | Related Articles | Metrics

Application of 3-C Seismic Prospecting Technique in Guang'an Area, Sichuan, China ZHANG Ming, GAN Li-deng, LI Ling-gao, DAI Xiao-feng, DU Wen-hui, ZHANG Xin 2007, 28 (4):  504-506.  Abstract ( 88 )   PDF (287KB) ( 216 )   Save For the serious heterogeneity of Xujiahe reservoir of Upper Triassic in Guang'an area, Sichuan, China, it is hard to accurately predict the gas-bearing intervals using conventional P-wave seismic prospecting technique. 3-C seismic prospecting technique can be used to get more subsurface information and better identify the features of reservoir rocks and fluids, hence decreasing the multi-resolution from it. Based on the high-quality 3-C seismic data available, several seismic processing techniques such as converted wave static correction, transfer point computation, converted wave velocity analysis and dynamic correction are used for obtaining abundant wavefield information and distinctive features of wave groups in this paper. And the composite interpretation of P-wave impedance inversion profile and converted wave elastic impedance inversion profile has allowed to effectively predict the distribution of favorable reservoir rocks and gain some preliminary results in this area. References | Related Articles | Metrics

Composite Imaging of VSP with Surface-Seismic Data GUO Xu-guang, YUE You-xi, ZHANG Jun-duo 2007, 28 (4):  507-509.  Abstract ( 108 )   PDF (154KB) ( 236 )   Save VSP observation system is different from surface seismic prospecting, including geophone arrangement and wave field feature, etc. Split-step Fourier method is used to extrapolate wave field and stack observational wave field at every extrapolation step, by which the integrated imaging of VSP with surface seismic data is gained. The wave fields given by different observation systems can compensate each other in the process of imaging, thus improving the quality of imaging. The theoretical models show that integration of VSP with surface seismic data can make more precise imaging of studied strata. References | Related Articles | Metrics

An Evaluation of Productivity from Expansion Screen Completion YU Tao, QI Da-sheng 2007, 28 (4):  510-512.  Abstract ( 74 )   PDF (175KB) ( 386 )   Save By theoretical analysis and experiment, the productivity of well completion with expansion screen pipe is studied and compared with conventional mechanical sand control completion. Also, the comparative estimation for screen completion and gravel pack completion is made respectively. The results show that the expansion screen completion is more advantageous in open hole completion than in cased hole completion compared with the mechanical sand control completion. References | Related Articles | Metrics

A Discussion on Several Issues about Fault Sealing WANG Dong-ye, ZHA Ming, WU Kong-you 2007, 28 (4):  513-515.  Abstract ( 87 )   PDF (138KB) ( 207 )   Save Fault sealing is characterized by heterogeneities both in time and space. Based on the analysis of the deposition, tectonic and stress field evolution, using shale smears and section stress methods, a quantitative research on lateral or vertical sealing of fault in different stages is conducted, and a comprehensive evaluation of them is made integrated with other influenced factors. The evaluation standards are different because of the difference between the fault seal oil ability and the fault seal gas ability. Study indicates that the evaluation of fault sealing with synthetic fuzzy judgment is more believable than some methods with incomplete consideration of influenced factors. Besides, the analysis of fault sealing with uncertainty method is indispensable to evaluate the confidence levels of all methods for fault sealing study. References | Related Articles | Metrics

Petroleum Explorative Potentials in 416a-417 Block of Oued Mya Basin, Algeria YANG Jun, WANG Yong-gang, JI Hong-jun, WENG Wang-fei 2007, 28 (4):  516-520.  Abstract ( 112 )   PDF (187KB) ( 208 )   Save The 416a-417 block of Oued Mya basin is located in the middle-northern Algeria. There are only 2D seismic data available now, the exploration degree is relatively low. This paper presents the analysis of source conditions, reservoir-cap rock assemblage, hydrocarbon migration and accumulation model and control factors as well as drilling response, petroleum enrichment and distribution analyses. Integrated with play assessment result, the structural zone in the 416a-417 block is optimized. It is pointed out that HJ-5 and JH-6 structural traps lie in favorable area of source rocks development, which are the targets for petroleum migration with predominant conditions of hydrocarbon accumulation, large sealing area and amplitude. Because of high degree of study and good condition of collocation, this block could be a preferred target for petroleum prospecting in this area. References | Related Articles | Metrics