Table of Content

01 February 2011, Volume 32 Issue 1 Previous Issue    Next Issue

For Selected:

Download Citations EndNote Reference Manager ProCite BibTeX RefWorks

Toggle Thumbnails

Study on Tertiary Oil Charges to Typical Structures in Western Qaidam Basin LI Xian-qing, ZHONG Ning-ning, WANG Kang-dong, ZHANG Min, PENG De-hua, ZHANG Zhi-jun, DUN Ya-peng 2011, 32 (1):  1-3.  Abstract ( 93 )   PDF (261KB) ( 257 )   Save According to analyses of grains with oil inclusions (GOI), quantitative grain fluorescence (QGF), homogenization temperature of fluid inclusion (HTI), the Tertiary oil charges to four typical structures (Yuejing-1, Youshashan, Nanyishan and Jiandingshan) in Western Qaidam basin are studied in this paper, showing that there exist charges of difference: for Yuejing-1 and Youshashan structures stronger oil charges occur during $N^{1}_{2}$-$N^{3}_{2}$, with high GOI value (mostly 4%~10%) and high QGF intensity (more than 50 pc); for Nanyishan and Jiandingshan structures relatively weak oil charges appear during $N^{2}_{2}$-$N^{3}_{2}$, with lower GOI value (mostly less than 4%) and lower QGF intensity (less than 50 pc) in their reservoirs. References | Related Articles | Metrics

Favorable Targets for Shale Gas Exploration in Tuha Basin SUN Yu-kai, LI Xin-ning, HE Ren-zhong, WANG Rui-ying, SUN Mei-li, YU Fa-zheng 2011, 32 (1):  4-5.  Abstract ( 128 )   PDF (207KB) ( 284 )   Save The key parameters of the shale gas reservoirs abroad are analyzed, and the principles of strategic areas for exploring shale gas at home and abroad are reviewed. Based on the geological conditions in Tuha basin, the general evaluation standards of these areas, the basic geological conditions of forming shale gas reservoirs for two sets of shale strata of Shuixigou group and Xiaoquangou group in this basin are evaluated comhensively. It is suggested that the eastern Taibei sag and the Hamisanbao sag in Tuha basin are favorable targets for shale gas exploration. References | Related Articles | Metrics

Lithofacies of Volcanic Rocks from Zhongguai Swell to District-5 and District-8 in Northwestern Margin of Junggar Basin ZHANG Shun-cun, YAO Wei-jiang, XING Chen-zhi, JIA Chun-ming, SHI Ji-an, LI Bing 2011, 32 (1):  7-10.  Abstract ( 84 )   PDF (540KB) ( 262 )   Save The core observation, slices appraisal, well-logging and logging data analysis are conducted for study of volcanic lithologies of Carboniferous and Permian from Zhongguai swell to District-5 and District-8 in northwestern margin of Junggar basin, combining with seismic data interpretation. On the basis of single well facies and section facies analyses, the plane distribution map of lithofacies of Carboniferous and sub-group of Jiamuhe formation of Permian is plotted. The Carboniferous in this area is dominated by volcanic rocks, with some andesites in the northeast, central and southwest; tuff in vast east area and the south, volcanic-sedimentary rocks in the southwest, these multi-rocks in the northwest, and volcanic breccia and basalt scattered near the west. The sub-group of Jiamuhe is also divided into two sections, from bottom to top, the rocks has some continuity with Carboniferous, but the lithofacies of upper section shows increase of andesite and volcanic-sedimentary rocks, and decrease of basalt and tuff, which may owing to volcanic activity tending to diminish and cease. References | Related Articles | Metrics

Evaluation of Paleogene Dingqinghu Source Rocks in Dongcuo Basin, Tibet ZENG Jing, LI Ya-lin, WANG Li-cheng 2011, 32 (1):  11-13.  Abstract ( 101 )   PDF (247KB) ( 316 )   Save Dongcuo basin located in the central Tibet is a Tertiary continental basin, which is mainly composed of Neogene Kangtuo formation, Paleogene Dingqinghu formation and Niubao formation. The stratigraphy, sedimentary facies analysis indicates that the source rocks are dominated by mudstone, marl and limestone of Dingqinghu formation with a maximum thickness of mudstone of 40 m, carbonate rocks of 72 m. The TOC of marl and limestone averages 0.51%, belonging to medium-good source rocks. The TOC of the dark mudstone in lower section of Dingqinghu formation in semi-deep lake facies averages 5.92%, classifying as high-quality source rocks. The organic matters are dominated by Type I and TypeⅡ. The Tmax (431~456℃) and Ro (0.36%~0.66%) suggest that the source rocks of Dingqinghu formation reach the early maturity, being of good hydrocarbon-genetic potential and explorative prospecting in Dongcuo basin. References | Related Articles | Metrics

Characteristic of Tight Sandstone Gas Reservoir in Tuha Basin and Its Exploration Target WANG Jin-song, WANG Wen-hui, MOU Lan-sheng, LIU Hu-chuang, SONG Hai-bo, SONG Cheng-wen 2011, 32 (1):  14-17.  Abstract ( 77 )   PDF (267KB) ( 259 )   Save The Shuixigou group of Jurassic in Tuha basin has geologic conditions for forming large-area tight sandstone gas reservoir. Long-term and great amount gaseous hydrocarbon generation and expulsion provide good preconditions for forming tight sandstone gas reservoir. The source rocks and reservoir rocks appear in interbedded contact relations which are favorable for inter-source gas accumulation in the tight sandstone reservoir. The gas migration and accumulation in the tight sandstone reservoir are quite different from those in conventional gas reservoir. In condition of piston-like gas charging, the water cut in tight sandstone gas reservoir is obviously high, and high or low pressure anomaly occurs. Under effective assemblages of the source and reservoir rocks, the south slope and north piedmont thrust belt in Tuha basin are favorable areas for exploration of tight sandstone gas reservoirs. References | Related Articles | Metrics

The Accommodation Transformation and the Distribution of oil pools in Faulted Lake Basin—An example from the third member of Shahejie formation in Dongying sag YANG Wei-li, WANG Yi, JIANG Zai-xing, SUN Yu 2011, 32 (1):  18-20.  Abstract ( 75 )   PDF (402KB) ( 185 )   Save The third member of Shahejie formation in Dongying sag consists of sequences of lacustrine transgression system tract (TST) and regression system tract (RST), of which the TST is the main control factor in tectonic subsidence, resulting in increase of accommodation space in the faulted lake basin and shape of dark shale source rocks from under-compensation deposits; the RST is the main factor in sedimentary material supply, as a result of forming accommodation transformation zone in central ramp and central sdeep slope, decreased accommondation space at outer side and increased accommondation space at inner side of the zone. In plane, the formation and distribution of petroleum reservoirs are closely related to the distribution of accommondation space, indicating that the accommondation transformation zone is the most favorable area for hydrocarbon accumulation, especially, the centralized distribution area for lithologic reservoirs, while the accommondation decreasing zone is the main area for structural-fault block reservoirs, the accommondation increasing zone will become oil reservoirs formed by slump turbidite sand bodies. References | Related Articles | Metrics

Abnormal High-Pressure and Deep Glutinite Oil Reservoir—An example from glutinite of steep slope belt in northern Chezhen, Jiyang depression FAN Zhen-feng, ZHANG Jin-liang 2011, 32 (1):  21-22.  Abstract ( 85 )   PDF (230KB) ( 218 )   Save The Glutinite body in steep slope belt in halfgraben-like faulted basin is characterized by poor property of reservoir due to deep burial, which can not be served as an effective oil reservoir. But the existence of abnormal high pressure in it allows the reservoir quality to be improved and of significance in hydrocarbon migration and accumulation in this belt. By means of method of lab analysis, well logging and geological study, the distribution of pressure field of the steep slope belt in northern Chezhen of Jiyang depression and the origin of its abnormal high pressure are analyzed, and the relationship between the abnormal high pressure and hydrocarbon accumulation is presented. This paper will be significant to glutinite reservoir exploration in other areas. References | Related Articles | Metrics

Diageneses and Reservior Characteristics of Nantun Formation in Sudeerte Oilfield XIAO Ying-ying, FAN Tai-liang, WANG Hong-yu 2011, 32 (1):  23-25.  Abstract ( 87 )   PDF (525KB) ( 312 )   Save In Sudeerte oilfield, I-IV oil measures of Nantun formation belong to a volcanoclastic reservoir with lithologies of tuffaceous conglomerate, tuffaceous glutenite, tuffaceous sandstone and tuffaceous mudstone. Compaction, cementation, devitrication, mineral cleavage crack and blast trace are its main diageneses. The reservoir physical properties are poor on the whole, but I-III oil measures are relatively bigger and IV oil measure is much smaller than I-III in porosity and permeability. The particle size has decided effect on the reservoir properties, namely, the bigger the particle size is the better the reservoir properties are. Compaction and cementation are the main factors to make the reservoir properties poorer, while devitrication and mineral cleavage crack and blast trace have some favorable effects on them. References | Related Articles | Metrics

Characteristics and Grade Evaluation of Tight Sandstone Reservoirs of Xujiahe Formation in Sichuan Basin XU Zhao-hui, WANG Ze-cheng, XU An-na, BIAN Cong-sheng 2011, 32 (1):  26-28.  Abstract ( 71 )   PDF (344KB) ( 287 )   Save The core analysis data and mercury injection analysis data are used to study the micro-feature of Xujiahe tight reservoir of the Upper Triassic in Sichuan basin, and its position of "continuous spectrum" of worldwide reservoirs is determined. By means of statistical approach, this paper classifies the grade of the tight reservoir according to its permeability and pore-throat radius and analyzes the value-distributive range of each grade reservoir parameters. From the intrinsic relations among the pore-throat radius, porosity and permeability, the fitting formula among them is given, by which the conventional physical data are conversed into the pore-throat radius, hence deducing the grade that reservoir belongs and obtaining other parameters of the reservoir for the purpose of providing a new idea for research of the tight sandstone reservoir of Xujiahe formation in Sichuan basin. References | Related Articles | Metrics

Application of High-Accuracy 3D Seismic Data Interpretation Technique to Zhagan Sag LIANG Guo-sheng, CHEN Qing-tang, WANG Shi-kun 2011, 32 (1):  29-31.  Abstract ( 95 )   PDF (513KB) ( 221 )   Save Taking high-accuracy 3D seismic data coverage in Zhagan sag as an example, starting with seismic fine calibration, the means like coherent strata slices, variable velocity diagram, balanced profile and lithology trap prediction are applied to well solving the distribution of complex structure and fault system and the description of reservoirs in this area, the obvious explorative effectiveness has been achieved, which are valuable to other similar areas in geology. References | Related Articles | Metrics

Prediction of Reef-Flat Reservoirs Based on Time-Frequency Analysis and Wave Impedance Inversion in M Region ZHANG Zhi-wei, HE Zhen-hua, HUANG De-ji 2011, 32 (1):  32-34.  Abstract ( 81 )   PDF (449KB) ( 262 )   Save There are a large number of reef-flat reservoirs founded in South China Sea, which have the characteristics of deep burial, uneven oil/gas distribution and difficult exploration. Low-frequency shadow and frequency attenuation gradient are two time-frequency analysis methods based on theory of wavelet transform spectral decomposition, which are closely related with the fluid of reservoir, not only as important indicators of fluid identification, but also determining the lateral distribution of a reservoir, except for identification of its top and bottom boundaries. While as one of important methods for reservoir prediction, the wave impedance inversion can make use of the advantage of log data's high vertical resolution to effectively distinguish them. Therefore, combination of these two methods can be better to predict reservoir location in M region, and finely characterize the lateral and vertical distribution of reservoir and oil/gas enrichment range in higher accuracy of prediction. References | Related Articles | Metrics

Prediction of Favorable Carboniferous Volcanic Reservoirs in Malang Sag, Santanghu Basin MOU Ke-xun, ZHANG Jin-xue, LIU Bo, FAN Tan-guang, MA Jian 2011, 32 (1):  35-38.  Abstract ( 74 )   PDF (343KB) ( 214 )   Save Based on the mechanism of volcanic eruption and the drilling and seismic data, the seismic response feature of volcanic facies in Santanghy basin, by which the favorable volcanic facies belts are attained. Through attribute analysis, pre-stack and post-stack inversions and fracture prediction approach, the favorable reservoirs are predicted in this paper. it is as a guide for further exploration of volcanic reservoirs in this area. References | Related Articles | Metrics

Evaluation of Low-Resistivity Reservoirs ZHANG Zhao-hui, GAO Chu-qiao, LIU Hua-qing, SU Ming-jun, CHEN Xiao-xin 2011, 32 (1):  39-41.  Abstract ( 74 )   PDF (315KB) ( 290 )   Save The exploration practices of hydrocarbon-bearing basins in China show that low-resistivity reservoirs are of abundant reserves and high productivity as the important exploration areas for increase of reserves and production in oilfield. Also, they are the main targets for reviews of old wells. However, the complexity and diversity of low-resistivity geneses cause difficult logging evaluations. And the main control genesis-based logging evaluation techniques should be used. In view of the low-resistivity reservoir caused by the high irreducible water content, this paper presents a model for oil-water relative permeability based on percolation theory of multiphase fluids in porous media and lab experimental results, using multiple non-linear regression method, by which such a reservoir can be evaluated using oilwater relative permeability data, on the basis of exact determination of water saturation and irreducible water saturation. Case study indicates that this method is simple to use and makes the success ratio of interpretation greatly improved. References | Related Articles | Metrics

Sedimentary Features of Carboniferous in Bashituo Block in Tarim Basin ZHANG Ru-jia, LIU Chun-yun, GUO Feng 2011, 32 (1):  42-44.  Abstract ( 68 )   PDF (255KB) ( 382 )   Save The Carboniferous in Bashituo block of Tarim basin is divided into Bachu formation, Karrathayi formation and Xiaohaizi formation, with rock types of clastic rock, carbonate rock and laminated gypsolyte. The sedimentary facies is dominated by carbonate platform which includes three sub-facies of evaporation platform, restricted platform, open platform and six micro-facies. In the late Bachu the source area was retrograded towards north and northeast direction, and the terrigenous clastics trended towards rapid decrease, forming a set of bioclastic-enriched carbonate strata-restricted platform sub-facies deposit. The early-middle Karrathayi belongs to evaporation platform mixed with restricted platform sub-facies deposit, and the late Karrathayi to restricted platform environment. Xiaohaizi period was featured with open platform sub-facies deposit by the enlarging of transgression. References | Related Articles | Metrics

A Method for Determination of Water Coning Shape of Fractured-Vuggy Layered Reservoirs with Bottom Water LV Ai-min, YAO Jun, WANG Wei 2011, 32 (1):  45-48.  Abstract ( 91 )   PDF (290KB) ( 358 )   Save In view of the shortage of effective approach for calculating the critical production and predicting the water coning in fracturedvuggy layered reservoirs with bottom water when drilling inside vugs, a method for domain decomposition is adopted, considering the different flow mechanical characteristics and flow variation between inside and outside of vugs, a calculating formula is put forward to describe the water coning shape under critical production based on binomial and linear flow models. The method for getting the key parameters from steady well test data at early stage of development is presented, of which the critical production can be calculated with trial method. The case study indicates that the water coning inside vugs forms peak shape nearby well bore and quickly declines outward as flat shape. The water coning shape outside vugs is obviously different from the inside, whose shape is in gradual flat from the inside to the outside. References | Related Articles | Metrics

Features of Water-Drive Curves of Low-Permeability Sandstone Reservoirs in Daqing Peripheral Oilfields ZOU Cun-you, WANG Guo-hui 2011, 32 (1):  49-50.  Abstract ( 95 )   PDF (207KB) ( 272 )   Save Type-A,-B,-C and -D water-drive curves are applied to calculation of the recoverable reserves of 35 low-permeability blocks in Daqing peripheral oilfields, and the corresponding water cuts when the straight line segments of water-drive curves appeared have been ascertained. The application results indicate that the recoverable reserve calculated by Type-C curves is the highest among the four types, and then Type-B, Type-A and Type-D in turn, which are different with those of middle- and high-permeability reservoirs. For the peripheral low-permeability reservoirs, the straight-line-segment water cuts when the water drive curve appeared are about 20.8% in average, much lower than those for high-permeability reservoirs. Such a last understanding has also been verified by other low-permeability oilfields in China. References | Related Articles | Metrics

Distribution of Remained Condensate in Yaha-23 Condensate Gas Reservoir JIAO Yu-wei, LI Bao-zhu, WU Di, ZHANG Xue-lei, YAN Jian-ye, XIE Wei 2011, 32 (1):  51-53.  Abstract ( 110 )   PDF (234KB) ( 229 )   Save As a condensate gas reservoir with high content of condensate oil, Taha-23 condensate gas reservoir is developed by dry-gas reinjection process for EOR. At present, the main problem during its development is that gas-condensate ratios of a part of wells increase quickly, causing rapid decline of condensate production and poor reinjection effectiveness. This paper analyzes the geological feature of the reservoir, describes its heterogeneity and researches the production profile testing, tracer testing and well production performance. It is suggested that gas breakthrough is the main reason for the high gas-condensate ratios. Therefore, the numerical simulation of production performance is conducted, including dry-gas reinjection advancing, gas-water phase behavior features and their saturation variations. Finally, the remained high condensate areas are determined. These provide solid bases for development adjustment, EOR and improvement of dry-gas reinjection effectiveness. References | Related Articles | Metrics

Development of Reservoir Numerical Simulator with Finite Element Method YANG Jun-zheng, WANG Xu-gang, WANG Rui-he, SHAN Wen-wen, ZOU Hong-lan, ZHOU Yong-fa, XIAO Jie, LI Feng 2011, 32 (1):  54-56.  Abstract ( 88 )   PDF (382KB) ( 255 )   Save Based on superposition principle of finite element (FE) calculation, a new method for flow rate control within finite volume (FV) is proposed, by which the reservoir numerical simulator combined with FE and FV on a finite element platform can be developed. By this method, the flow rate within controlled volume is calculated only by means of FV method rather than grid classification of FV and its calculated amount for boundary flow rate within control volume is less than that by one time by traditional FV method, thus greatly decreasing the calculating amount and programming difficulty, increasing the efficiency of reservoir numerical simulation. References | Related Articles | Metrics

Theoretical Relationship Between Cumulative Water Storage Rate, Cumulative Water Drive Index and Water Cut WANG Zuo-qian, HUANG Shu-nv 2011, 32 (1):  57-59.  Abstract ( 151 )   PDF (308KB) ( 357 )   Save By waterflooding process, the water storage rate and the water drive index are significant indices that reflect utilization status of injected water energy and comprehensively evaluate waterflooding effectiveness of oilfields. In view of existence of wrong correlation formula between cumulative water storage rate, cumulative water drive index and water cut on many literatures, this paper deduces correct theoretical relationships or formulae between them in terms of definitions of cumulative water storage rate and cumulative water drive index, integrated with six water drive characteristic curves recommended by the Oil and Natural Gas Standard. Using the series of formulae, the effective evaluation of water injection adaptability and waterfooding effectiveness in waterflooding oilfields can be made correctly. References | Related Articles | Metrics

New Method for Calculation of Critical Production of Horizontal Well in Bottom Water Reservoir CHENG Xiao-jun, YI Bin, DENG Yong, LI Su, ZHU Meng 2011, 32 (1):  60-62.  Abstract ( 84 )   PDF (276KB) ( 322 )   Save The key of using horizontal well to develop bottom water reservoir is to determine the critical production. Based on the analysis of water coning mechanism, the 3D percolation field of horizontal well is approximately divided into two parts including internal and external percolation fields. The two streamline distributions are analyzed. First, the Dupuit formula is used to get the formula of critical production for external field. Second, the horizontal length is taken as "reservoir thickness" and the distance between wellbore and reservoir top is taken as "drainage radius", and then the formula of critical production for internal field is given by using radial flow theory. Last, combining with the rule of equivalent filtrational resistance, a new method for calculation of the critical production of a horizontal well in bottom water reservoir is proposed. The case study is conducted and the comparisons among the different methods are presented. The effects of anisotropy, horizontal length and ratio of horizontal section's vertical distance and reservoir thickness on the critical production are analyzed. References | Related Articles | Metrics

Waterflooding Pattern for Fractured-Vuggy Reservoir in Tahe Oilfield, Tarim Basin MA Xu-jie, LIU Pei-liang, HE Chang-jiang 2011, 32 (1):  63-65.  Abstract ( 80 )   PDF (208KB) ( 357 )   Save The Ordovician reservoir in Tahe oilfield is a karst fractured-vuggy oil reservoir dominated by large-sized vugs as its reservoir spaces. At present, breakthrough has been made by single well waterflooding process, but it is in experimental stage by multi-well unit waterflooding process for areas with 80% reserves. Based on the numerical simulation and waterflooding practices, the mechanism of the mult-well unit waterflooding process is studied, and an effective pattern in field application is preliminarily summarized in this paper, namely, low water injection and high oil production, injection test to judge connectivity and adjust in time, whole unit gentle water injection and well groups separation management References | Related Articles | Metrics

Description Method for Oil-Water Microscopic Distribution During Water Flooding Process YIN Guang-ming, LI Xing-min, YIN Yin 2011, 32 (1):  66-67.  Abstract ( 91 )   PDF (208KB) ( 275 )   Save It is significant to study water-drive micro-mechanism and the distribution of residual oil in porous media for enhancing water drive efficiency. Based on an understanding of pore distribution characteristic and water-drive micro-mechanism in porous medium, in view of pore structure with single-peak logarithm normal distribution, a method for quantitative description of oil-water micro-distribution under initial condition and water-drive process is proposed in this paper. The calculation result shows that this method can directly reflect the relationship between sweep efficiency and oil-water micro-distribution during water drive process, and can be applied to analysis of pore structure with binormal and multi-peak distribution. References | Related Articles | Metrics

Study on Percolation Behavior of New Soft Movable Micro-Gel YE Yin-zhu, WANG Zheng-bo 2011, 32 (1):  68-70.  Abstract ( 107 )   PDF (282KB) ( 261 )   Save At present, new soft movable micro-gel (SMG) depth profile control has become one of the important EOR techniques for old oilfields. By lab displacement experiment, the percolation mechanism of SMG system in porous medium is studied, the percolation model is developed, the equation analytical solution is given. The effective filtrating factor is defined as characterizing factor of SMG system. The model's parameters are analyzed systematically. The research shows that the results could have methodological and theoretical reference values on the analysis and calculation of injection concentration distribution and injection pressure variation and the determination of effective range of SMG solution in porous medium. References | Related Articles | Metrics

Determination of Gas Well’s Deliverability for Underground Gas Storage in Yong-21 Block in Yong’an Oilfield XU Yao-Dong 2011, 32 (1):  71-73.  Abstract ( 112 )   PDF (242KB) ( 160 )   Save The underground gas storage will be constructed in Yong-21 block that is abandoned gas poor in Shengli oil-gas area for the purpose of working in domestic gas long-transmission pipe line network construction, meeting the demand for natural gas from Shandong region and ensuring the safe and steady gas supply for city and town of the region. At present, the gas pool reservoir of Yong-21 block has been watered out, it’s difficult to restore to initial water saturation by gas injection process. Therefore gas-water two-phase flow exists during construction or operation of underground gas storage, and along with the change of operation cycle, the water saturation changes unceasingly, the gas well’s deliverability can also unceasingly change. In this paper, the gas well’s deliverability equation for Yong-21 block in condition of water free using the well test and production test data from old gas wells is presented. Based on the result of gas-water displacement physical simulation experiment study, the equation between gas relative permeability and injection-production multiple of Yong 21 block is presented. Through revision of gas relative permeability of the deliverability formula, the gas well’s deliverability equations in different operation cycles are also given. These have solved the difficult problems of gas well’s deliverability calculation in underground gas storage with water production. References | Related Articles | Metrics

Logging Identification Technique of Oil and Water Layers in Fractured-Vuggy Reservoir in Tahe Oilfield 2011, 32 (1):  74-76.  Abstract ( 64 )   PDF (258KB) ( 315 )   Save The Ordovician reservoir in Tahe oilfield is characterized by strong heterogeneity, developed fractures and vugs, complicated oil-water relation, no uniform oil-water interface. Based on the logging evaluation and formation testing data, as well as statistical log response characteristics from lots of oil and water intervals, this paper presents the crossplots of resistivity-porosity and gamma rayresistivity, P-S wave ratio approach, normal distribution approach and comprehensive discrimination approach to fluid property, by which proposes identification index for quantitative calculation of oil and water layers. The case study in Tahe oilfield shows that the coincidence rate for recognition of oil and water layers has reached above 75% for the purpose of making completion program and determinating reserves parameters. References | Related Articles | Metrics

Experimental Research on Chemical Demulsification for Emulsified and Visbreaking Heavy Oil in Z-70 District of Huabei Oilfield GUO Ying, LIANG Jin-lu, LUO Jian-hui, DING Bin, WANG Ping-mei 2011, 32 (1):  77-79.  Abstract ( 106 )   PDF (179KB) ( 290 )   Save The visbreaking of heavy oil is the key technology for the heavy oil development and gathering. However, it will bring some new challenges to its following demulsification and dehydration treatment. This paper selects the typical heavy oil emulsion as the basis for chemical demulsification and adopts light scattering-based automatic detection method to evaluate and analyze the real-time dynamic dehydration speed and rate systematically. In contrast with traditional bottle-test method, by the new method the efficiency and accuracy can be improved greatly. The oil content ratio of dehydration and the water content ratio of purified oil are evaluated, indicating that the heavy oil system after visbreaking treatment followed by chemical demulsification and dehydration is suitable for field requirement. References | Related Articles | Metrics

Automatic Recognition and Suppression of Abnormal Energy Seismic Trace by Method for Amplitude Attenuation and Frequency Division WANG Zai-min, ZHU Jiang, LI Lei, JIANG Li, TAN Jia 2011, 32 (1):  80-82.  Abstract ( 104 )   PDF (980KB) ( 318 )   Save According to the comparison of amplitude attenuation curves between abnormal energy seismic tract and normal seismic tract without amplitude compensation, it is suggested that the amplitude attenuation of normal seismic trace after eliminating the influence of surface wave is much greater than the abnormal energy seismic trace. The latter can be recognized by means of average absolute value amplitude ratio within the same window length at the beginning and the end of seismic traces as the scale for the amplitude attenuation. When the abnormal energy concentrates at or near a frequency, it can be recognized and eliminated by the scale in frequency division data. The recent-year seismic data processing indicates that the automatic recognition and suppression of abnormal energy seismic trace by method for amplitude attenuation and frequency division is feasible and significant, especially for the processing of 3D seismic data acquired at low signal-to-noise ratio area. References | Related Articles | Metrics

Common-Reflection-Surface Stack Imaging Method (CRS-OIS) and Application in Junggar Basin Based on Output Trace Imaging LOU Bing, ZHENG Hong-ming, GUO Hong-xian, Fan Xu, ZHANG Jing 2011, 32 (1):  83-84.  Abstract ( 97 )   PDF (344KB) ( 201 )   Save CRS-OIS is a method for realizing common-reflection-surface (CRS) stack imaging from output traces imaging. The method is of big difference from traditional methods in the fact that it not only gives a high-quality stack profile, but also provides high-quality pre-stack gather. These are of well applied values for improvement of pre-stack imaging quality of data with low signal-to-noise ratio. The method is applied to the piedmont of the southern margin of Junggar basin and proves to be effective and feasible. References | Related Articles | Metrics

Calculation of Shear Wave Velocity Using Xu-White Model for Fluid Displacement ZENG Zhong-yu, CHEN Zhao-nian, ZHONG De-ying, ZENG Dong-dong 2011, 32 (1):  85-88.  Abstract ( 108 )   PDF (429KB) ( 261 )   Save In the pre-stack elastic impedance inversion, since the shear wave time difference log data are frequently not gained, the rock Poisson ratio cannot be accurately calculated. For this reason, the compressional wave time difference, formation density, shale content, porosity, water saturation and a variety of rock matrix and fluid elastic parameters are sufficiently used to develop Xu-White model for fluid displacement and get the shear wave time difference. This method is used for calculation of shear wave time differences of Well PMNA-001 at M block, Well F18B-29 and Well F18B-116 at F block in MBTL area. The results show that compared with the actually measured shear wave timedifference for these wells, the errors are small, completely meeting the demands of elastic wave inversion and oil-gas prediction. References | Related Articles | Metrics

Acid Fracturing Technique for Fractured-Vuggy Carbonate Reservoir by Horizontal Well Process in Tahe Oil Field GENG Yu-di, ZHANG Ye, HAN Zhong-yan, ZHAO Wen-na 2011, 32 (1):  89-91.  Abstract ( 122 )   PDF (254KB) ( 252 )   Save In view of the characteristics of fractured-vuggy carbonate reservoir in Tahe oil field, to achieve the average modification of acid fracturing for long open hole and improve the acid fracturing effect for horizontal well to the full extent,a series of researches have been made,which include acidizing fluid system optimization, technology optimization and tool improving, then the acid fracturing technique for sidetrack horizontal well in Tahe oil field is presented and good effect has been obtained in field application. References | Related Articles | Metrics

Approach to Contact Relation Between Xiaoquangou Group and Cangfanggou Group in Junggar Basin PENG Xi-ling, YUAN Wen-xian, LIU Chao-rong, HU Bin, LAI Shi-xin 2011, 32 (1):  92-96.  Abstract ( 122 )   PDF (1030KB) ( 335 )   Save The relationship between Xiaoquangou group of the Middle-Upper Triassic and underlying Cangfanggou group of the Lower Triassic in Junggar basin has been considered to be conformable and continuous. However, a great number of information indicate that the central and northern parts of this basin belong to a large unconformity in regional distribution, and the upper Cangfanggou group is absent to a large extent except for the southern area of the basin. The discovery of this unconformity has been delayed 5 years, while the universal confirmation of it has delayed more than 20 years due to restriction of traditional ideas. The key for thoroughly solving this big problem attributes to the drillings of Moshen-1 well and Shimo-1 well. References | Related Articles | Metrics

Relationship Between Emei Mantle Plume and Aulacogens of Guangwang-Kaijiang-Liangping YAO Jun-hui, LUO Zhi-li, SUN Wei, WANG Rui-jing 2011, 32 (1):  97-101.  Abstract ( 160 )   PDF (732KB) ( 379 )   Save The tectonic-sedimentary setting of Puguang gas field in Sichuan basin was differently named by researchers when it was discovered. This paper suggests a terminology of aulacogen for the setting from point of view of plate tectonics and Emei taphrogeny, by which existence of Mianzhu-Zhongjiang aulacogen in western Sichuan basin is predicted and confirmed with the discovery of Pengxi-Wusheng concave platform in central Sichuan. It is concluded that the west Hubei, Guangwang-Kaijiang-Liangping and Mianzhu-Pengxi-Wusheng aulacogen groups developed in the western margin of Yangtze platform are resulted from the integrated process of three geological tectonic elements, and the dominant contributor is the dynamics of Emei mantle plume. These aulacogen groups possess potentials of natural gas prospecting. References | Related Articles | Metrics

A Discussion on Results Interpretation Again of Higher Measured Rock Compressibility WANG Li-qiang, LI Zheng-ke, SHEN Hong, LUO Yang-jun, TANG Xi-ming, ZHANG Zhong-jin, WEN Jing 2011, 32 (1):  102-103.  Abstract ( 148 )   PDF (130KB) ( 240 )   Save Based on the Reference [1], the reason of higher measured rock compressibility is due to the skin effect of cores. This paper believes that this kind of effect does exist in lab experiment, but it is not the main reason of it. The main reason is that equation for porosity compressibility is sensible to porosity volume in low porosity sample. On the basis of comprehensive analysis of rock stress, this paper proposes a new regulation equation, which gets over the fault of equation from the Reference [1] and provides right relationship of compressibility vs porosity. These results are significant to correct understanding of the reason of higher measured rock compressibility in lab experiment, proper correction and computation of it in reservoir engineering. References | Related Articles | Metrics