, Volume 31 Issue 1
    

  • Select all
    |
    专家论坛
  • Discussion and analysis of superimposed sedi-mentary basins
    HE Dengfa; JIA Chengzao; TONG Xiaoguang and WANG Guihong
    , 2004, 31(1): 745-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The Chinese Continent is situated in the transitional tectonic domain between the Siberian and Gondwana Continent. It had been controlled sequentially by the Paleo-Asian Ocean dynamic system, the Tethys and Paleo-Pacific dynamic system, and the India Ocean and the Pacific Ocean dynamic system since the Sinian Period. Its mainland is composed of small continental blocks such as the North China, the Yangtze, the South China, and Tarim blocks etc. as well as so many micro-continental blocks, which are located in several large-scale orogenic belts. The sedimentary basins developed on the base of or at the margin of the mentioned above continental blocks is mostly of superimposed basins. The superimposed basin has been resulted either from the composition of proto-type basin during the same stage and the superimposition of proto-type basin of different stages. It has undergone drastic periods of tectonic trans-formation during the different dynamic system stages. The two mega cycles, one of which began with the break-up of Rodinia Continent since the Late Proterozoic and ended with the formation of the Pangea in the Triassic, and the other began with the break-up of the Pangea in the Jurassic Period and ended with the convergence of discrete plates, has accordingly resulted in different types of superimposed basin before or after the Triassic in China. Because of the sub-cycles of extension and compression during each mega cycle, the extension and the compression system or the strike-slip system transformed each other frequently, which induced the multiple periods of drastic tectonic transformation, leading to the multiple superimposition of the proto-type basins. The Chinese sedimentary basins are characterized by the poly-history superimposed basins with a character of distinctive oil and gas accumulation and distribution.
  • Progress in the study of natural gas in China
    SONG Yan; CHEN Mengjin; QIN Shengfei and QIU Mingxiang
    , 2004, 31(1): 746-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    In the last decade, much progress has been made on the study of natural gas and several hypothesis for the origin of natural gas were proposed. They are: ①The origin of natural gas, including coal-formed gas, biogenic gas-thermal catalysis transitional belt gas, and none-biogenic gas；②reservoir formation of natural gas, including migration-accumulation equilibrium, late formed reservoir, and the deep basin gas；and ③concerning the accumulation of natural gas,the hypotheses include gas-generating center control mechanisms, the regional seal control, the paleo-uplift control, and the foreland basin natural gas concentration
  • A key idea for finding oils in an area of high developed
    ZHANG Shanwen
    , 2004, 31(1): 747-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Jiyang Depression has been explored for 42 years. Some of the disciplinarian cognition and systemic theory is absolute and they will become a thought "trap" which can prevent progresses and innovating. It's no doubt that the huge breakthrough in exploration, gained by innovating in cognition, theory and technology at some stage of exploration, has driven the development of oil and gas exploration. At the same time, these cognitions, theories and technologies are basically fit with the definite exploration stage. Exploring in the area of highly exploration should bravely use the deal precisely with concrete matters relating to work, deep the cognition of the inner rule of the genesis and mechanism of oil and gas and make them to be the systemic and more perfect theory.
    • 石油地质研究
  • Modeling experiments of generation mechanism of Yingkou-Tongerbu fracture zone in the Liaohe Depression
    SHAN Jiazeng; ZHANG Zhanwen; SUN Hongjun; XIAO Qianhua; XU Kun; JIN Jian and WANG Daojing
    , 2004, 31(1): 748-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The Yingkou-Tongerbu fracture zone is a major structural system of controlling formation and evolution of the East Sag, Liaohe Depression, and the extended part of Tanlu Fault Zone northward. The geological information analyses and studies of the modeling experiments suggest that the Yingkou-Tongerbu fracture zone has underwent a composite action of older extensional stresses and younger dextral shear stresses in Cenozoic. The extensional structure movement occurred during the sedimentary phase of Fangshenpao Formation, Paleocene and Shahejie Formation in age of Eocene (37-63Ma). The upwelling of the mantle during evolutionary stage of the continental rift generates the extensional stresses. The dextral strike-slip structural movement occurred in sedimentary phase of the Dongying Formation, Oligocene ( 24.5-36.9 Ma ). Action of younger dextral strike-slip structural movement reactivated older extensional fractures and produced new fractures. The results from modeling experiments and analyses of geological information suggest that the displacement magnitudes of the Liaohe Depression caused by dextral strike-slip structural movement during the Paleogene should be about 4-8km
  • The fault structure and its controlling role to hydrocarbon accumulation in Daqingzijing area, Southern Songliao Basin
    LI Jianzhong; YANG Tao; WANG Liwu and JIANG Tao
    , 2004, 31(1): 749-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The fault structure and its controlling role to hydrocarbon accumulation in Daqingzijing area are analyzed based on 3-D seismic and drilling data. There are mainly NE strike and NW strike two fault systems in this area. The NE strike central fault was the major basement fault, which had left-lateral strike slip behaviour and controlled the development of NNW strike and NW strike secondary faults. There developed three NW strike secondary faults in the west of central fault with horst-graben interval change pattern, whereas it was a gentle SW dip slope with few faults developed in the east of central fault. The faults were the important migration pathway of oil and gas, and controlled the formation of structural traps and lithologic traps. The central fault controlled the overall hydrocarbon distribution of Daqingzijing area by ways of controlling the faults development level and deformation style of both sides: it was mainly structural and structure-lithologic oil pools which distributed on three faulted horsts on the west side; and formed large-area lithologic oil pools on the east.
  • Transfer zone and its relative reservoir distri-bution in northern zone of Dongying Sag
    SUN Xiangyang and REN Jianye
    , 2004, 31(1): 750-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Two sets faults developed in the northern zone of Dongying Sag, between which transfer zones occur act as displacement transfer. Transfer zone is one of the important components developed in northern zone of Dongying Sag, which is characterized by a series of faults with small displacement. Its strike has a little difference with that of the main faults systems. Significant difference characteristics exist between transfer zone and its surroundings. Subsidence center is far from the faults. Ramps are the typical feature of transfer zone and this physiography is the favor area for drainage flowing to basin. Sand body that restrained by transfer zone is characterized by large thickness and range. Lithologic reservoir and complex reservoir are the main potential types in the study area.
  • Relationship between paleogeothermal and hydrocarbon formation in the Yanqi Basin, Northwest China
    YAO Yaming; ZHANG Yumin; FU Daiguo; YANG Yibin; CHEN Tianke and WANG Pugui
    , 2004, 31(1): 751-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The AFTA (Apatite Fission Track Analysis), inclusion thermometry, determination of isotopic age of authigenous chilkinite, etc. have been used to reconstruct the paleogeothermal in the Yanqi Basin, Northwest China. The AFTA results suggest a heating paleogeothermal in north sag that means the highest paleogeothermal of strata was consistent with present geothermal; the inclusion thermometry（101-110℃ and 121-130℃） suggests a cooling geothermal that means paleo-geothermal is higher than present geothermal in south sag and Zhongmachang faults belt; the isotopic age of authigenous chilkinite shows that hydrocarbon generation and accumulation existed two periods in the depression, Late Cretaceous the Yanshan period, the one is after Eocene, Himalaya period. The research on paleogeothermal shows that there are two periods of hydrocarbon generation in Jurassic strata in north sag: Late Jurassic-Early Cretaceous and the one after Tertiary, respectively. In south sag and Zhongmachang faults belt, the main hydrocarbon formation existed merely in Late Jurassic and Early Cretaceous. The Yanshan period sediment and the structures of Himalaya are favorable regions for exploration in north sag, but in south sag, the ancient structures formed before Himalaya period are the favorable play target.
  • Episodic reservoir-formation rules in the Jungar Basin, Northwest China
    TAN Mingyou; ZHANG Yunyin; SONG Chuanchun and LIU Guohong
    , 2004, 31(1): 752-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The oil and gas fields in the Jungar Basin are generated in multi-episodes reservoir-formation, reconstruction and late adjustment. Five episodes, asⅡ Episode of Indo-Chinese epoch ( Late Triassic), Ⅱ Episode of Yan Shan ( Late Jurassic), Ⅳ Episode of Yan-shan ( Late Cretaceous), Ⅱ Episode of Himalayan ( Late Eocene) and Ⅲ Episode of Himalayan ( Late Neogene), are divided preliminarily according to the main tectonic phase, oil generation period, transport system and reservoir-formation period of oil and gas fields. The zones, in the north slope of Dongdaohaizi Sag, the SE of Mahu Sag, the north of Luliang Oilfield and NE slope of Changji Sag, would be the favorable areas for exploration of large and middle scaled oil and gas fields. The main target is Jurassic-Cretaceous in which the main reservoirs are subtle ones.
  • Influences of high temperature and overpressure on the thermal evolution of organic matter in the Ying-Qiong Basins, South China Sea
    YI Ping; HUANG Baojia; HUANG Yiwen and WANG Feiyu
    , 2004, 31(1): 753-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    On the basis of vitrinite reflectance data in 10 wells in the high temperature and overpressured strata, the Ying-Qiong Basins as well as an artificial pyrolysis experiment, the influence of high temperature and overpressure on the thermal evolution of organic matter for hydrocarbon generation has been investigated. The results suggest that high temperature has an important effect on the thermal evolution and hydrocarbon generation of organic matter and especially in areas where the source rocks were intensely influenced by deeply sourced hot fluids, and the rapid heating rate resulted in an advanced evolution of organic matter deposited in a shallower burial depth
  • Advances in the correlation of oils and source in the Jiuxi Depression, Northwest China
    XIONG Ying; CHENG Keming; YANG Zhiming; GAO Bo and HU Yong
    , 2004, 31(1): 754-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The Lower Cretaceous lacustrine mudstone and marl (K1c, K1g, K1z) in the Jiuxi Depression have long been recognized as the source rock for hundreds of millions tons oil in place. Biomarker and carbon isotopic composition indicate that the oils are quite similar geochemically but the geochemical characteristics of source rocks have differente evident though all source rock share some common characteristics of lacustrine depositional environment. Kerogen carbon isotopic composition, Pr/Ph and biomarker are the key indicators to genetically separate the source rock samples into six groups. The source rocks of the lower part of Xiagou Formation (K1g) have good relationship with that of the upper part of Chijinpu Formation (K1c), while the rest of the source rocks have obvious differences revealing a strong heterogeneity. Based on the detailed oil-source correlation,including the thermal maturity, carbon isotopic compositions and biomarker, Group Ⅴand Ⅵ source rocks should be the main contributors of the crude oils.
  • The genesis of viscous crude and asphalt of Qingxi Oilfield in Jiuquan Basin, Northwest China
    FAN Mingtao; YANG Zhiming; TIAN Baozhong; YUE Zhizhong and LI Tao
    , 2004, 31(1): 755-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Much crude oil of the Qingxi Oilfield in Jiuquan Basin, northwest China has a normal density. However, the viscous crude and asphalt are found in some exploration wells. The study of the genesis mechanism of viscous crude and asphalt is helpful for resolving the long argued problems of the evolution and periods of the source rocks. The physical property and geochemistry parameters analysis of the viscous crude and asphalt reveals that both of them come from the same source rock and they are in the maturation state. The correlation of 17 indexes,including native rock property, sedimentary envi-ronment, maturity and microbial action,suggests both of them come from the same source rock and they are in the maturation state. The genesis of viscous crude is attributed to the crude oil mixing of internal reservoirs and the reservoir differentiation, while the viscous crude is generated from the mixture of crude oil in reservoirs and the reservoir rock differentiation and asphalt is generated by the gas de-asphalt of the associated gas of the oils
  • 25-norhopane in the source rock of Santanghu Basin and the function of microbe degradation
    DU Hongyu; WANG Tieguan; HU Jian-li and XU Guifang
    , 2004, 31(1): 756-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    25-norhopane is obvious distribute within the source rock of Upper Permian Malang Sag, Santanghu Basin, Northwest China and the biomarker from microbe is real abundance and the autogenetic mineral pitch matrix is dominant distributed. Based on comparative analysis, it could be confirmed that the source rock had been exposed to the microbe degradation in the period of deposition or forepart diagenesis, and the 25-norhopane comes from the original materials of hopane degrading.
  • A correlation between content of iron element and organic carbon in the source rocks, Late Permian to Early Triassic in the Shiwandashan Basin，South China
    HE Zhongfa; BIAN Lizeng; CHEN Jianping; ZHANG Shuichang; WEI Baodong; LU Guijun and ZHANG Baomin
    , 2004, 31(1): 757-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Abundance of iron in source rocks is effected by many factors,such as climate, different geological period, marine biomass, seawater natures and the kinds of sea floor. The interpreted of the sources rock of Late Permian to Early Triassic in the Shiwandashan Basin in Guangxi, China suggest that there is a good correlation between the content of organic carbon and the content of iron element in the argillaceous facies of the shallower shelf. The content of iron element in the argillaceous facies of the shallower shelf offered a kind of distinctive data source as biomass. The studies of correlation between the content of organic carbon and iron element would be present some important information for stratigraphic correlation and sedimentary environments identification.
  • Paleogene stratigraphic frames in the Shubei Area, Liaohe Depression
    REN Desheng; LIU Li; CHEN Jiang; ZHOU Xingwu and WANG Jing
    , 2004, 31(1): 758-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Shubei Area is located in the northern section of western sag of Liaohe Depression. Four sequences consisting of fan delta lacustrine sedimentary system are identified in the synrift setting supersequence based on the comprehensive research of seismic, logging curve and application of time-frequency analysis technology, including 11 systems tracts. A set of thickness dark shale and oil shale is frequently developed between TST and HST, which are considered condensed section and the principle oil source rock and capping rock; the marginal areas of all systems would be advantage reservoirs. Gaosheng reservoir is a set of the transaggressive systems tract sediment of sequenceⅠ, Dujiatai reservoir is a set of the high-stand systems tract sediment of SequenceⅠ, Lianhua reservoir, a set of the transgressive systems tract sediment of SequenceⅡ. Gaosheng reservoir should be the best reservoir in the Shubei Area. It is clearly that the aggressive systems tract sand developed in the largest transaggressive period is the best reservoir
  • The developed and evaluated patterns of Ordo-vician palaeo-karst in the Huanghua Depression
    XIA Riyuan and TANG Jiansheng
    , 2004, 31(1): 759-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The Ordovician palaeo-karst had gone through 3 evolution stages and there are 7 types of developed patterns in the Huanghua Depression. The first stage was from Late Caledonides to Early Hercynian Period, and two exposed palaeo-karst types of erosion depression discharge in syncline wings and intermountain depression discharge in syncline axle developed. The second stage was from Indochina to early Yanshan Period, and divided into exposed palaeo-karst in karst dome-depression and shallow buried palaeo-karst in down-faulted basin. The third stage was from Late Yanshan to Himalayan Period, and there were three types of compaction-released water karst at inclined fortress block areas and deeply buried faulted convex areas and hot water karst at high level inclined block in big faulted zones. The strongly karstification overlapping areas of three periods are most favorable for oil and gas accumulation.
  • Fractures in the Lower Cretaceous reservoir of Qingxi Oilfield, Jiuxi Depression, Northwest China
    YAN Weipeng; ZHU Xiaomin; GU Li; ZHANG Qunwei; ZHANG Zhensheng and WANG Xiaoshan
    , 2004, 31(1): 760-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The reservoirs in Qingxi Oilfield of Jiuxi Depression composite compact fracture oil traps. The types of fractures are mainly structural dip fissure and pie-shaped fissure. The fractures' width range between 0.5-2.0mm and development of micro-fissures has the function of connection. Two groups of fractures developed in the Qingxi Oilfield, one strike is NE-SW and another strike is NW-SE. The main strike is NE-SW. Most of the effective fractures are formed in the Himalayan Period. The best development region of fractures is the south and the east parts of Qingxi Oilfield, which are fine reservoir spaces and migration passages since their formation time was matched well with hydrocarbon expelling stage.
  • Characteristics and generating mechanism of Permian relative low-density sandstone in Sulige Gas Field, Northwest China
    ZHANG Wencai; GU Daihong; ZHAO Ying; LIU Pengcheng and LI Hui-jun
    , 2004, 31(1): 761-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The sandstone in No.1 member of Shanxi Formation and No.8 member of Xiashihezi Formation, in age of Permian, in the Sulige Area are mainly low density (<2.45g/cm3) and with thickness of 2-3m. The sandstone is of good reservoir quality, represented by porosity ( higher than 8%) and permeability (0.3×10－3μm2), high gas saturation（>45%） and a high production(mostly higher than 10×104 m3), which is the major pay zones. The relative low-density sandstone composites of quartz sandstone with more 90% middle to coarse quartz and less cements among the grain, specially, some bitumen could be found within the pores. The acid liquid is moveable and stronger dissolution and later oil and gas charging should be the key factors for generating such low-density sandstone.
    • 综合勘探开发技术
  • Hydrogen isotopic compositions of individual n-alkanes in terrestrial source rocks
    XIONG Yongqiang; GENG Ansong; PAN Changchun; LIU De-yong; LI Chao and PENG Pingan
    , 2004, 31(1): 762-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The gas chromatography - thermal conversion - isotope ratio mass spectrometry (GC-TC-IRMS) has been used to measure the hydrogen isotopic compositions of individual lipids in different terrestrial depositional environment: Liaohe Basin and the Turpan Basin, China. The analytical results indicate that the δD values of individual n-alkanes in the extracts of terrestrial source rocks exhibit larger variation, ranging from -250‰ to -140‰, and are obviously lighter than those of marine n-alkanes. Moreover, a trend of depletion in deuterium (D) is observed in individual n-alkanes from different terrestrial depositional environment, from saline lacustrine (δD range from－200‰ to －140‰); swamp (δD range from－250‰ to －200‰); and freshwater paralic lacustrine – lacustrine environment fall between the values for the former two end members. The shift toward lighter hydrogen isotopic compositions from saltwater to freshwater environment indicates that depositional paleoenvironment is the major controlling factor for the hydrogen isotopic compositions of individual compounds. Hydrogen exchange between formation water and sedimentary organic matter has possibly played an important role in regard to the hydrogen isotopic compositions of individual n-alkanes. Other geochemical evidences would be incorporated into when depositional paleoenvironment of source rocks is reconstructed based on the hydrogen isotopic compositions of individual n-alkanes.
  • Vertical seal ability of faults to hydrocarbon in southern Junggar Basin, Northwest China
    YUAN Zhengwen; WANG Zhenliang; HE Mingxi; SONG Jianhua and GU Zhe
    , 2004, 31(1): 763-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Abundant faults are developed in west part of southern Junggar Basin, and the anticlines in Tianshan foreland thrust belt are usually be cut by the faults. Because of being abnormal high pressure, possibility of opening faults is increased, so the fault is a main pathway of upward migration of hydrocarbon from overlying Jurassic source rock, as well as the thrust developed in compressive environment. The nature of vertical seal of faults is more important for controlling degree of rich accumulation of hydrocarbon. By means of the theoretical model of fault vertical seal, the vertical seal of faults in three structures of Anjihai, Dunan and Tugulu are evaluated. It is discovered that in condition of distribution of fluid pressure, etc, the vertical seal of several faults in same area is obvious different, and the seal may be sharply different in some depth of the same fault.
  • Stochastic modeling of sand framework of deltaic front
    LI Shaohua; ZHANG Changmin; WANG Zhenqi and HE Zhenming
    , 2004, 31(1): 764-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Prototype model with 40 meters surveying line spacing and corresponding geological knowledge database are established according to the fine study on the outcrops of Chang 6 and Chang 7 stratum, which are emerged well in the Yanhe profile located in Ordos Basin. The reservoir framework model of Tanjiahe profile（key profile）is built under condition of not using some surveying lines, with a spacing of 80,120 and 160 meters, respectively. The stochastic simulation arithmetic used is sequential indicator simulation and 50 realizations are produced. The comparing with simulated and original profile by using layer number, average thickness and percent of thickness of different lithology as criterions, it is clearly that the model is reliable and has high forecasting precision and is a practical and useful tool for establishing a forecasting model of reservoir.
  • An integrated study on the Banqiao oil layer in the middle area of Banqiao Oilfield
    LIANG Baoqin; ZUO Songhua; LI Hui-peng and LENG Ji-chuan
    , 2004, 31(1): 765-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The structure acreage of Banqiao oil formation is 60km2, in where over 200 wells were drilled. A integrated study has been being carried on since 2002, including seismic, geological and logging information by using the technique of layer demarcate and structure subtly interpretation on the small faults and structure high. Water channel sand body and water channel side sand body are main petroliferous sand body depending to the analyses of micro-sedimentary facies and the types of sand body. Based on the results, seven wells are drilled within 3 fault blocks and all wells acquire high productive oil-gas flow. It is demonstrated that increased oil-bearing area 1.9km2 and oil reserves 120×104t.
  • Progressive exploration of fluvial facies reservoir in the No.1 block of Gangdong Oilfield
    ZHU Wenchun; SONG Kun; GAO Yinjun; LI Shuqing; ZHANG Yingshan and LIU Pengcheng
    , 2004, 31(1): 766-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    According to the current state of Gangdong Oilfield, a set of means for progressive exploration play on the first block of Gangdong are proposed, that is based on sedimentary facies research and integrated information of seismic, geology, logging, drilling, including: ① to identify the distribution of reservoir according to precise stratigraphic correlation and sedimentary facies research; ②to proposal the targets for progressive exploration based on the predicts of sandstone developed zones according to the seismic information;③to decide the exploration wells by using the seismic data and neural network; ④ to determine and quantitatively calculate the single sand body’ boundary according to the seismic and log information. The excellent results have been got in 7 wells based on the plays that are made according to the predicting.
  • Heterogeneity of conglomerate reservoir in the Menggulin Oilfield, Erlian Basin
    XIAO Wei; LIU Zhen; QU Zhihao; LI Jihong and YANG Yajuan
    , 2004, 31(1): 767-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The reservoirs in the Menggulin Oilfield are developed in a progressive developing braided channel and in a normal composite rhythm, with strong heterogeneity. The distribution of permeability and reservoirs are controlled by the sedimentary microfacies and the mud content, the best reservoirs mainly distributed in the braided channel micorfacies, better reservoirs are in the subaqueous channel, the worse reservoirs, in the subaqueous channel flank and the non-reservoirs in the subaqueous breach. The development and stability of tight sand or conglomerate interbed and the shale band are all gradually changing better from the northwest to southeast. There are the low quantity of interbed, the low stability and connectivity in the braided channel micorfacies, there are the higher quantity interbed, the higher stability and connectivity in the subaqueous breach, the interbasin and underwater channel flank microfacies.
  • Pyrolysis quantitative evaluation on the light crude oil-producing layer in Hailaer Basin, Northeast China
    LANG Dongsheng; JIANG Daohua and CHEN Yubin
    , 2004, 31(1): 768-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The summarization of the pyrolysis data acquired with drilling in Hailaer Basin, and with the well testing data since 1996, and connected with pyrolysis parameters and crude oil properties and dynamic productivity indexes could be able to set up a pyrolysis quantitative evaluation method about crude oil properties in light crude oil-producing formation and properties of fluid producing layer in reservoirs. By using this method, light oil layers could be found in time and evaluated quantitatively, and believable planning could be proposed for oil test. The coincidence rate for evaluating the properties of fluid producing layer has increased from about 60% to more than 95% nowadays. The application of the productivity prediction method has also gained better effect.
  • Oil layer connectivity in the sixth block of Gudong Oilfield,the evidence from gas chromatography fingerprint technique
    WEN Zhigang; ZHU Dan; LI Yuquan and ZHANG Guo-rong
    , 2004, 31(1): 769-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    A gas chromatography fingerprint technique can be used to study oil layers connectivity. Oil samples obtained from three main oil layers in 8 wells in the sixth block of Gudong Oilfield of Shengli oil area were analyzed by whole oil gas chromatography technique. Comparing the gas chroma-tography characteristics of single layer oil samples, fluid connectivity in single layer among wells can be identified. The results from reservoir geological studies have proved that conclusions about the oil layers connectivity on the basis of the gas chromatography fingerprint characteristics of oil samples are correct.
    • 油田开发与油藏工程
  • Thermal recovery numerical simulation coupling flow in reservoir with various-mass-rate flow in horizontal well-bore
    WU Shuhong; YU Li-jun; LIU Xiange and GUO Shangping
    , 2004, 31(1): 770-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    In order to describe the actual flow of fluid in and nearby the horizontal well, it is necessary to study the coupling of the flow in the reservoir with various-mass-rate flow in the horizontal well-bore. An assumption is given that the horizontal well-bore is divided into several micro-elements and the fluid flows into the horizontal well-bore only at the interface of the two nearby micro-elements, which results in constant-mass-rate flow in any micro-elements. An equivalent seepage flow model is built for the various-mass-rate flow in the horizontal well-bore by using the staggered grid and equivalent permeability. A thermal recovery numerical simulation model coupling the flow in the reservoir with various-mass-rate flow in the horizontal well-bore is constructed. A recovery mechanism study of horizontal wells is carried out with the coupling model built and several important results are obtained. The pressure drop within the horizontal well-bore has influence on the production performance of the well. If neglecting the pressure drop along the well-bore, the calculated production parameters such as oil production and oil-steam ratio will be higher than the true values. The most oil production is derived from the production end (the first end) of the well-bore. Under a certain condition (certain reservoir condition, horizontal well parameters and so on), there exists an optimum horizontal well-bore length.
  • Impacts of permeability heterogeneity on horizontal well productivity
    GUO Xiao and DU Zhimin
    , 2004, 31(1): 771-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Based on Joshi et al’s assumption，a 3-D drainage problem was reduced to two 2-D solution problems，the 9 productivity formulae for horizontal wells in heterogeneous reservoirs is presented by using geometric，arithmetic and harmonic average to modify the horizontal and vertical permeability in the mapped equations. The impacts of permeability heterogeneity on the productivity of horizontal wells were analyzed. The results show that horizontal well productivity generally decreases with increase in the ratio of horizontal to vertical permeability and reservoir thickness. However，its impact on horizontal well productivity is not very efficient if the reservoir thickness exceeds a certain limit. Furthermore，oil production is usually under-predicted by the model developed by arithmetic average and the models of vertical permeability modified by geometric and harmonic average can explain why horizontal well productivity increases apparently with increase in the ratio of horizontal to vertical permeability in thin oil formation.
  • Stable permeating flow and productivity analysis for anisotropic reservoirs in horizontal well networks
    LIU Yuetian and ZHANG Jichang
    , 2004, 31(1): 772-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    By using coordinate transformation, an anisotropic reservoir can be mathematically modeled as an isotropic reservoir, and the morphology of a well-bore and a well network have therefore also been conceptually modified. With Elliptical Cosine conformal transformation, each rectangular unit of a well network is modeled to an ellipse. The isopressure boundary of a well-bore therefore becomes an ellipse and a horizontal well is projected to the center of this ellipse. The flow pattern, pressure distribution, and flow intensity of a given anisotropic reservoir can be derived from the known elliptical flow pattern. When anisotropy of permeability increases and the prevailing permeability becomes parallel to the well alignment in a network, the permeating flow and production in a 5-point well network with anisotropic permeability have the following characters: ① the productivity is inversely proportional to the anisotrophy of permeability;② the flows becomes closer to parallel when the anisotrophy of permeability increases; and ③ the distance between the breakthrough point of injected water moves further away from the end of a horizontal well network.
  • A new analysis method of modified isochronal test data
    TANG Junwei and CHEN Caihong
    , 2004, 31(1): 773-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    There are two defects in the analysis method of the conventional modified isochronal test data, especially in the low permeability gas well with small control reserve of a single well. One is that the binomial coefficient is lower than the true value, even becomes negative in some cases. Another is that the stabilized point coordinate is not calculated according to its definition strictly. Based on the radial transient flow equation and the superposition principle, a corrected formula for calculating the unstabilized and stabilized binomial equation is obtained by analyzing the whole procedure of the modified isochronal test. The data of the analog well and Well Su-6 in Sulige Gas Field, Northwest China, were processed. It reveals that the corrected method can deal with those data which can't be analyzed by the traditional one, and that the result is more reliable and more precise.
  • Economic development plan for viscous crude marginal pool of thin multilateral sand and shale
    ZHANG Renling and TANG Xiangming
    , 2004, 31(1): 774-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    It is more risky for developing a marginal pool than that of conventional one, the feasibility must be evaluated by integrate its developing strategy and economic benefits. Block Wei 5 of the Jiangsu Oilfield is a marginal field with middle and low permeability and the thin multilateral sand and shale. The microcosmic research on the oil displacement and quantitative simulation results indicate that oil displacement and development are hardly affected by the injection water temperatures. The startup pressures are high and the displacement efficiencies are low in both kinds of experiments of oil displacement by waters with different temperature and carbon dioxide soak. Using depleted water injection method and cyclic steam stimulation can economically develop this kind of oil reservoir, or steam soaks and then water injection successively. According to the results of pilot tests in the area, modified water injection should be used in the development of Block Wei 5 viscous crude reservoir. Water injection effect can be improved by depressing the water injection. Productivities of suitable single well can be increased by hydraulic fracturing with short fractures. All of oil production rate, development efficiency and total economic benefit can be increased when some suitable wells are operated by cyclic steam stimulation.
  • A method of calculating productivity for gravel packed well
    LI Aifen; YAO Jun and KOU Yongqiang
    , 2004, 31(1): 775-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Four different flow patterns around the gravel-packed well could be divided: the radial flow from the supply boundary to well bore, the spherical flow near the perforations, the linear flow through the perforations and the diverging flow from perforations to screen. The mathematic models for resistance to a single fluid flow in each region are built, including the effect of the turbulent flow near the perforations. The sensitive parameters have been studied by the calculation, and the productivity of one gravel-packed well of Shengli Oilfield has been studied by using these models. The results show that the pressure losses in the well bore obtained using linear flow model, radial flow model and diverging flow model is difference greatly, which implies that errors will arise when using only the former two models. The pressure loss mainly occurs in the perforations. When the perforation is filled with formation sand, the pressure loss will be 48% of the total loss, while only 29% of the total pressure loss occurs when the perforation is filled with gravel. In order to improve the productivity of gravel-packed well, the perforation and its nearby region should be filled with gravels.
  • The black oil sand in Wennan Oilfield, Dongpu Sag
    HONG Yu and SHANG Bo
    , 2004, 31(1): 776-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Black oil sand presents in the lower section of Es2 in the Wennan Oilfield, Dongpu Sag, the black material composite of mainly heavy oil, resin and bitumen, etc, which is a type of interlayer preventing the fluid contained in the leading pay formation from flowing, affecting the effect of exploitation and causing the losing of some high grade reserves. The analyses of the distributing law, the lithology, the physical property, the electrical characteristic and the organic component of the black oil sand suggest that the black oil sand is formed mainly because of the change of the inside condition that make the light hydrocarbon dissipating and the depositing of heavy component and accumulating. Black oil sand has potential for explorations in future.
  • Methodology of economic evaluation of stimu-lation treatment
    YE Zhengrong; WU Qi; WANG Liangang; ZHAO Chun; GONG Lin; ZHAO Zhihong and JIANG Haijun
    , 2004, 31(1): 777-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    For evaluating economic benefit of stimulation treatment reasonably, to distinguish and calculate the expense and benefit properly should be a premise. The incremental analysis is considered and the attention must be given to the total evaluation index, and the incremental operation cost only contains the payments and downhole operating expenditure that is connected to the stimulation treatment directly. The treatments more than one year validity is evaluated with the dynamic method, however, the ones less than one year validity are suitable with the static method. For static method, the cost is dealt with payment, the treatment input is considered as downhole operating expenditure, the evaluation indexes are the incremental profit, incremental net profit and profit ratio. For dynamic method, the cost is dealt with investments; the indexes are composed of the incremental profit ratio of investment, the incremental financial net present value and the ratio of incremental financial net present value ratio. The benefits of several stimulation treatments are calculated, such as hydraulic fracturing, water shutoff, and pump change. The results show that the methodology of economic evaluation of stimulation treatment can reflect the economic benefit of stimulation treatments.
    • 油田非注水开发
  • Application of micro-gel flooding technology in the Henan Xiaermen Oilfield
    FAN Zhonghai; KONG Bailing; SHE Yueming and TANG Jinlong
    , 2004, 31(1): 778-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The technology of micro-gel flooding （low concentration cross-linking HPAM）can be used under the conditions of high polymer concentration but is unstable in high salinity brines at elevated temperature. The Cr3＋／HPAM system of 0.4g/L HPAM and 0.06g/L Cr3＋, prepared by using the Xiaermen Oilfield water produced in the Xiaermen Oilfield, for 180d at 50℃ at a consistent viscosity values of 130 mPa·s, were used as a flooding agent. The results from a single well injection practice and 5 injecting wells groups flooding pilot test show that gelling ability and injectivity of this system are excellent in the reservoir conditions. With an increase in the injection pressure from 5.0MPa to 10.5MPa, apparent injectivity index is reduced from 23.15m3/(d·MPa) to 12.34 m3/(d·MPa); compared with water flooding, the amount of change is higher than polymer flooding. Comparing with polymer flooding, the amounts of HPAM used are obviously reduced from 1.0g/L to 0.4g/L, chemical agent (polymer and crosslinker) cost is decreased by 21%. The ability of profile modification of micro-gel flooding is better than that of polymer flooding technology, with further improving the sweep efficiency of polymer flooding.
    • 油藏物理
  • Experiment of rock resistivity under formation conditions
    WANG Jian; LüChengyuan; HU Yong-hua and SUN Zhigang
    , 2004, 31(1): 779-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    The formation factor and the saturation index are measured and compared under both high temperature (80℃)/high pressure (15MPa) and normal temperature/pressure conditions. The results show that the formation factor is not sensitive to the temperature but to the net overburden pressure. The formation factor under high pressure is will have much effece than that under normal pressure. The saturation index is slightly sensitive to the temperature and sensitive to effective stress. The resistivity increment rate under both the above conditions varies slightly when the water saturation is higher. When the water saturation is low, the resistivity increment rate under high pressure is lower than that under low pressure. Compared to the surface conditions, the lithological coefficient a measured under formation conditions becomes larger, while the cementation index m, saturation index n and lithological coefficient b change to smaller. The water saturation calculated using the characteristic parameters measured under formation conditions is smaller than that under the surface conditions. The rock's resistivity parameters should be measured under the conditions wherein the actual effective stress of the simulated reservoir.
    • 油层保护与改造
  • The damage of reverse-condensate pollution of condensate on the formations of the Sulige Gas Field, Ordos Basin
    WANG Hua; TANG Hai and ZHANG Wenzheng
    , 2004, 31(1): 780-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    Only a little condensate had been found when some gas well are producing test in Sulige Gas Field, Ordos Basin. The analyses of relative permeability of 3 wells and 9 set cores under the condition of gas-oil and gas-water coexisting by using gas-free oil sample, gas sample, water sample show that permeability dropped slowly when water saturation increased from 0 to minimum original-water saturation and dropped sharply when minimum original-water saturation increased to maximum original-water saturation. The damage for real formation permeability is lower than that of experiment. According to the result from five well's phase experiment, the maximum volume of condensate is less than the whole volume of hydrocarbon when formation pressure drops down. Therefore, the damage of permeability that comes from condensate at medium-last development stage of Sulige Gas Field would be slight.
    • 学术讨论
  • Experiments on the abnormal pressure of source-contacting gas (basin-centered gas) accumulation
    ZHANG Jinchuan; LIU Lifang; ZHANG Jie and XUE Hui
    , 2004, 31(1): 781-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    A pressure-resistible glass tube with 7cm of inner diameter and 75 cm of height was adopted in the pressure experiments on source-contacting gas or basin-centered gas accumulation. After filled with red-dyed water, the glass tube was deposited with upward coursing sands of homogenized white quartz, whose grain diameters varied from 0.05 mm to 4 mm gradually in 15 segments of which the lower ones were connected respectively with piezometer tubes. In order to observe the variation process of fluid pressures in different sand segments, natural gas was injected into the glass tube from the bottom to simulate the piston-fashioned expelling of water by gas. The experiment result showed that the water over gas phenomenon occurred and abnormal pressures of fluids appeared in the segments in which sand grain diameters were less than 0.3 mm when the velocity of gas injection was relatively high while the sand grain diameters were less than 0.15-0.2 mm when the gas injection velocity was relatively lower. Regardless the gas injection velocities, there was nearly nothing to do with water over gas and overpressure when the sand grain diameters were greater than 0.3mm. According to the experiment results, typical source-contacting gas is accumulated by the advancing of isobaric surface and characterized of overpressure.
    • 国际交流与合作
  • Reservoir characterization of the Odovician oil and gas pools in the Tahe Oilfield,Tarim Basin, Northwest China
    ZHANG Kang; WANG Darui and Bryan G Huff
    , 2004, 31(1): 782-0.
    Abstract ( ) Download PDF ( ) Knowledge map Save
    About 88.1% of the proven reserves in the Tahe Oilfield in the Tarim Basin of Northwest China are trapped in Ordovician carbonate reservoirs. These reservoirs are formed by unconnected and interconnected networks of karstic porosity forming a heterogeneous and complex reservoir system. Oil, water and gas characteristics vary significantly in different portions of the Ordovician reservoir. There is no uniform oil/water contact in the field, adding to its complexity. An acid fracture treatment is beneficial in 76% of the wells, stimulating nonproductive wells and enhancing production in other wells by fracturing into unconnected reservoirs and enhancing flow pathways with acid. Acid fracture treatments should be a standard procedure for developing this and similar oil fields.
Office Online
Included
Most Popular
Links More
Visited
    Total visitors:
    Visitors of today:
    Now online:
Copyright © Petroleum Exploration and Development
Address:P. O. Box 910, No.20 Xueyuan Road, Haidian District, Beijing 100083, China
Powered by Beijing Magtech Co. Ltd.