2003 Vol. 25, No. 2

Display Method:
AN APPROACH TO OROGENESIS-COUPLED/DECOUPLED BASIN DEVELOPMENT AND ITS KINEMATICS
WU Gen-yao, MA Li
2003, 25(2): 99-109. doi: 10.11781/sysydz200302099
Abstract:
Orogenesis coupled/decoupled basin development was represented as a new thinking for study on oil and gas bearing basins.The soul of the new thinking was a tectonic outlook of mobilism on basin study,which called for two new emerging academic branches:orogen stratigraphy and orogen paleogeography.Two methods should be emphasized:the mechanical and historical synthetic analysis of geological structures and the analysis of basin geodynamics.Because of the complexity and multiplicity of relations between "basin" and "orogen",the prerequisite of basin orogen analysis was to give a time restriction,namely,a unified kinematic process and geodynamic mechanics between orogenesis and basin development would be discussed within a relatively short interval.The kinematics of "basin" "orogen" coupling could be explored from four aspects.1)Compression and tension should be interdependent spatially,and the attention be paid to some large or super large basins related to collision and post orogenic basins.2)There were two kinds of strike slip faults:one was a part of the global shearing net,whose importance in tectonics of China Continent was once neglected;another was what was in the same kinematic system with tensile or compressional faults.3)The contrains of deep sea ted courses resulted in tectonic overfly,the "basin"(or "orogen")of shallow structural layers being co e xisted with the "orogen"(or "basin")of deeper structural layers.4)Tectonic escape might be regarded as a combination of the transformation of strike slip faulting and the affection of deep seated courses,but the extension and strike slipping in escaping areas should have some distinct characters.The key to understanding the inheritance or decoupling of the Indosinian "basin" "orogen" relation was a tectonic differentiation between the west and east parts of the China SE Asia Subcontinent occurred from the Jurassic.The east part became a wide Yanshanides,where the Indosinian "basin" "orogen" relation was decoupled.A subduction type orogeny occurred in the west part in the Early Cretaceous,which did not decouple the Indosinian "basin" "orogen" relation.Sandwiched in between the both Yanshanides,there existed a relatively stable zone not involved in the Yanshanian orogeny,where the reformation of the Himalayan movement was the crux if basins were reserved and oil gas accumulation was formed.
SEDIMENTARY CHARACTERISTICS AND DEVELOPING BACKGROUND OF THE SUBLACUSTRINE FAN IN THE LIUSHAGANG FORMATION OF THE FUSHAN DEPRESSION, THE BEIBUWAN BASIN
LIU Li-jun, TONG Yan-ming, JI Yun-long, KUANG Hong-wei, LU Ming-guo
2003, 25(2): 110-115. doi: 10.11781/sysydz200302110
Abstract:
Some scale of sublacustrine fan deposit was developed in the Liushagang Formation of the Fushan Depression,the Beibuwan Basin.Three main sedimentary facies units can be recognized:turbidity current deposit,underwater debris flow deposit and olistostrome.The sublacustrine fan was developed in the lowstand and transgressive system of the Liushagang Formation.Some bidirectional down lapped reflection structures showed on seismic profiles.The characters of well logging curves are box,bell or funnel type.The sublacustrine fan was composed by three parts on the surface:the proximal,the middle and the distal part.The lower part of the sublacustrine fan vertically developed relatively thick incised valley infilled by gravity flow deposit.Many small turbidite fans accumulated on the vertical sequence.The development of the sublacustrine fan was controlled by the activity of the east and west bilateral faults of the basin,the supply of sediment sources and the change of lake surfaces.The bigger scale sublacustrine fan in the second episode of the Liushagang Formation was related to rapid structural subsidence and sufficient sediment supply.
THE MIDDLE JURASSIC SEDIMENTARY EVOLUTION AND PETROLEUM POTENTIAL OF THE MOHE BASIN
WU He-yong, XIN Ren-chen, YANG Jian-guo
2003, 25(2): 116-121. doi: 10.11781/sysydz200302116
Abstract:
The detail sedimentation study of the Middle Jurassic outcrops consisting of Xiufeng,Er-shierzhan,Emuerhe and Kaikukang formations respectively,indicated that alluvial fan,fan delta,braided river delta,lake floor fan and lacustrine facies were developed from Xiufeng to Kaikukang formations in the Middle Jurassic of the Mohe Basin.The alluvial fan and fan delta facies were developed in the Xiufeng formation,the braided river delta in the Ershierzhan and Emuerhe formations,alluvial fan and fan delta in the Kaikukang formation,and lake floor fan and lacustrine facies in all above formations.The sedimentary evolution from Xiufeng to Kaikukang formation was as alluvial fan fan delta lacustrine to braided river braided river delta lacustrine to alluvial fan fan delta lacustrine.Such a sedimentary evolution resulted in the development of source rocks,reservoirs and cap rocks.Therefore,there is petroleum potential in the Middle Jurassic of the Mohe Basin.
CHARACTERISTICS AND POOL-FORMING CONDITIONS OF THE LOWER ORDOVICIAN RESERVOIRS IN TAHE oil field, THE TARIM BASIN
WANG Dun-ze, LI Yu-zhan, YU Ren-lian
2003, 25(2): 122-128. doi: 10.11781/sysydz200302122
Abstract:
The integral geological study and petroleum exploration indicated that Tahe oil field formed on the basis of long developed paleo uplift was a large scale one which consisted of karst fracture reservoirs of the Lower Ordovician carbonate rocks.Karst holes,cracks and pores developed in the Lower Ordovician carbonate rock constitute four types of oil and gas reservoirs,including crack type,pore crack type,crack pore type and reef type.Long lasting generation of hydrocarbon,multiphase tectonic movement and multistage karstification resulted in quite different oil characteristics in different part of the oil field.Petroleum accumulation and pool forming were controlled by the Akekule Uplift,development level of karst fracture in carbonate rocks and distribution of mudstones of the Carboniferous Bachu Formation.
GEOLOGICAL MODEL OF THE MUGLAND BASIN-AN IDENTICAL EXAMPLE OF BASIN EVOLUTION AT THE END OF GIANT STRIKE-SLIP FAULTS
WEI Yong-pei, LIU Chi-yang
2003, 25(2): 129-136. doi: 10.11781/sysydz200302129
Abstract:
The basin evolution at the end of giant Central African strike slip fault is closely related to the regional tectonic background.Evolution of the basin in the Early Cretaceous resulted from the seperation of Atlatic Ocean,and that in the Later Cretaceous from the northward movement of the India plate.The spreading of Red Sea in the Cenozoic have also influenced the evolution of the basin.Three stages of the structural evolution for the basin can be classified:Early Cretaceous,Late Cretaceous and Cenozoic.In the Early Cretaceous,owing to activity of the central African strike slip fault,the subsidence speed was enormous,in which the depositional and subsiding centers were not in the same position.In the Late Cretaceous,the basin was dominated by both rifting and sag,and the depositional center moved towards the southeast of the basin where was far away from the central African fault.In general scene,the structural evolution for the basin was transformed from the strike slip to the extensional system.Potential source rocks and reservoirs were developed along the central African fault in the early evolution of the basin.Under the structural compression in the late stage,some oil and gas pools could be destroyed,and resulted in hydrocarbon redistribution and formation of new accumulations.The difference in depositional and subsiding centers brought out the difficulty in exploration.In the southeast of the basin far away from the central African fault,the main source rocks were matured properly,and depositional and subsiding centers were in the same place,so many industrial oil and gas fields have been found.
STRUCTURAL CHARACTERISTICS AND EVOLUTION IN THE LAIYANG DEPRESSION OF THE JIAOLAI BASIN
ZHAI Shen-de
2003, 25(2): 137-142. doi: 10.11781/sysydz200302137
Abstract:
The Laiyang Depression is a secondary structural unit of the residual basin developed in the Cretaceous period.There are obvious differences in terms of different periods of the Cretaceous deposition,an angled unconformity surface existing between the Upper and the Lower Cretaceous,and well developed folds and faults in the depression.The structural evolution history may be divided into five stages including pull apart faulted depression during the Laiyang period,the extensional faulted depression during the Qingshan period,compressed folding at the end of the Qingshan period,re pull apart faulted depression during the Wangshi period and uplifted erosion during the Cenozoic.The tectonic activity during the Early Cretaceous provided conditions of deposition of hydrocarbon source rocks,and tectonic movement occurred in the Late Cretaceous and the Cenozoic resulted in formation and adjustment of oil and gas pools.
STUDY ON THE INFILLING PATTERNS OF LACUSTRINE BASINS IN THE DONGYING DEPRESSION
ZHU Guang-you, JIN Qiang, ZHOU Jian-lin, ZHANG Lin-ye
2003, 25(2): 143-148. doi: 10.11781/sysydz200302143
Abstract:
The infilling patterns of lacustrine basins are the important means to evaluate the sedimentary characteristics of hydrocarbon source rocks.Combined with the geochemical characteristics of source rocks in this paper,the sedimentary succession of source rocks,the developing features of strata and the infilling and evolutionary process of basins in the Lower Triassic Shahejie Formation of the Dongying Depression were analysed.The source rocks of the Shahejie Formation can be divided into three evolutionary stages from lower to upper.The evaporite facies(the Upper Shasi Subformation),the oscillatory deep lake facies(the Lower Shasan Subformation)and the delta lacustrine facies(the Middle and Upper Shasan Subformation)assemblage patterns were established,which corresponding to underinfilling,equilibrium infilling and overinfilling lacustrine types respectively.They reflected the generation,spreading and consumption process of lakes.
RESOURCE POTENTIAL IN THE DEEP OF THE SHIWU FAULT DEPRESSION AND THE CHANGLING SAG, THE SONGLIAO BASIN
ZHU You-hong, WANG Jun
2003, 25(2): 149-152. doi: 10.11781/sysydz200302149
Abstract:
The lower part in Shiwu fault depression and Changling sag includes Yingcheng Formation(K1yc)、Shahezi Formation(K1sh)and other lower formations.The thickness of the main source rocks is large and its hydrocarbon generation quantity is about 86%-90% of the total.The sum of gas resources is 10.4×108t oil equivalent and the resource abundance is(7.64-15.09)×104t /km2.The deeper traps formed in the early stages with large areas could have priority condition to accumulate oil and gas.Discovery of this kind of accumulation is still in its early stage because of the olw exploration degree.There is favourable potential for petroleum exploration in the area.
A STUDY ON CONGLOMERATE RESERVOIR HETEROGENEITY AND RESIDUAL OIL DISTRIBUTION OF MEMBER A3 IN MENGGULIN AREA OF THE ERLIAN BASIN
LI Ji-hong, QU Zhi-hao, YUE Le-ping, XIAO Wei, YANG Ya-juan
2003, 25(2): 153-157. doi: 10.11781/sysydz200302153
Abstract:
Based on dynamic and static information of conglomerate reservoirs in Menggulin area of the Erlian basin,a fine description of heterogeneity of the conglo merate reservoirs has been given.The conglomerate belonged to sediments of a braided river delta.The sedimentation and diagenesis controlled macro distribution of the reservoir,intra bed rhythm,the distribution of inter beds and change of porosity and permeability.The conglomerate was massive structured in the northwest and showed bedded structure in southwest area.It is showed that distribution of residual oil is controlled by sedimentary micro facies,structural condition,relationship of injection and production.Residual oil is concentrated in the high part of local structure,the oil zone of masive reservoirs and the upper part of bedded reservoirs between injection wells in higher water cut stage.The reservoirs of subaqueous channel micro facies with middle to low permeability showed low water driving efficiency,are the rich area of residual oil distribution.
ANALYSIS ON THE FORMING MECHANISM OF THE CARBONIFEROUS GAS RESERVOIRS IN THE KAIJIANG PALEOHIGH REGION OF EAST SICHUAN AREA
XU Guo-sheng, ZHAO Yi-hua
2003, 25(2): 158-163. doi: 10.11781/sysydz200302158
Abstract:
East Sichuan area is a relative structre mobile belt in the stable blocks of the Sichuan Basin,in which ten lines of high steep structural belts were developed and major gas bearing structural belts are located in the Kaijiang Paleohigh region.The explored reserves of natural gas in East Sichuan area are about 60% of those in the whole Sichuan Province.This makes East Sichuan area,especially the Kaijiang Paleohigh region become the main producing zone of natural gas in Sichuan Province and even in China.In this paper,the forming mechanism of three kinds of the Carboniferous grouped gas reservoirs formed in the Kaijiang Paleohigh region was analysed emphatically.It was pointed out that the pool formation of the Kaijiang Paleohigh in the early stage and the rich Carboniferous gas sources laid a solid foundation for the formation of present great gasfields and grouped gas reservoirs,the Datianchi structural belt in the top of the Kaijiang Paleohigh is the most favorable gas enriched structural belt,and the grouped gas reservoirs of the inheritance anisotropic type are the main gas enriched type.
INFLUENCE OF THE DIAGENESIS OF CLAY MINERALS ON RESERVOIRS AND PRODUCTIVITY-A CASE STUDY ON THE FU-3 RESERVOIRS OF TAIXIN oil field, THE NORTH JIANGSU BASIN
CHENG Xiao-ling
2003, 25(2): 164-168. doi: 10.11781/sysydz200302164
Abstract:
On basis of X ray diffraction of clay minerals,analysis of resin cast thin sections of cores and SEM observation of samples in twelve wells,the clay mineral types and their distribution in four oil groups of the third member of Fuling Group in Taixin oil field,the northern Jiangsu Basin were described.The relationship between clay mineral types and porosity or pore structure of reservoirs was discussed.The inf luence of transform of clay minerals with geological evolution on reservoir character was analyzed.The results showed that kaolinite was positive correlation with porosity,but chlorite and illite were negative correlation with that.The chlorite showed obvious negative influence on preservation of porosity.Occurrence of secondary pores was accordance with the first rapid transform zonation of clay minerals in burial depth of 2 350-2 750m.The most favourable position for development of secondary pores was forecasted.
APPLICATION OF HIGH RESOLUTION SEQUENCE STRATIGRAPHY IN RESERVOIR PREDICTION
XIAO Yu-ru, HE Feng-yu
2003, 25(2): 169-173. doi: 10.11781/sysydz200302169
Abstract:
The development history of sequence stratigraphy was described and several advances in integrated stratigraphy developed from sequence stratigraphy were introduced.The features and applications of sequence stratigraphy in marine strata and continental strata and the high resolution sequence stratigraphy were discussed.The high resolution sequence stratigraphy will be comprehensively developed in the future and play a very important role in the reservoir correlation,prediction and simulation.The future development of the high resolution sequence stratigraphy may provide useful tools in 3D reservoir prediction and in study of reservoir heterogeneity and stratigraphic traps.
STRUCTURAL FEATURE AND PETROLEUM ACCUMULATION IN XIAERMEN oil field, THE BIYANG DEPRESSION
CHEN Wei-li, LIN She-qing, YANG Dao-qing, YAN Fu-wang, XIA Dong-ling, LIU Gui-lan
2003, 25(2): 174-177. doi: 10.11781/sysydz200302174
Abstract:
Based on 3D seismic data and well information and combining with regional tectonic background,the structural feature and its evolution were analyzed and formation history of hydrocarbon accumulation was restored in Xiaermen oil field.Xiaermen structure is an anticline complicated by the later faults.The tectonic activity at the end of Paleogene was characterized by compression and uplift,and folds were developed in Biyang depression.The faults in the depression were formed in the end of Neogene.The structural evolution and formation of hydrocarbon accumulations passed through 3 stages,i.e.(1)subsidence and deposition with development of reverse drag anticline in Early Paleogene,early migration and accumulation of hydrocarbon;(2)regional compression and uplift in the end of Paleogene,formation of anticline lithology reservoirs;and(3)extension and fault movement in the end of Neogene,complicated anticline,destruction of reservoir,and formation of secondary fault lithology reservoirs.
STUDY ON MICROSCOPIC WATER-DRIVE MECHANISM AND THE AFFECTING FACTORS OF WATER-DRIVE EFFICIENCY IN CHENBAO oil field, THE NORTH JIANGSU BASIN
LIU Bai-lin
2003, 25(2): 178-182. doi: 10.11781/sysydz200302178
Abstract:
Test techniques such as the oil water displacement test,the microscopic water drive test and the nuclear magnetic resonance were applied in this paper to study water drive mechanism and the affecting factors of water drive efficiency in the main oil layers of ChenBao oil field.The results showed that the difference of water drive efficiency within each sandlayer group of the oil field was mainly affected by the macroscopic heterogeneity of reservoirs,the small scopic heterogeneity of rocks and oil/water viscosity ratio,and was affected slightly by permeability in some range of permeability.On microscopic level,water drive efficiency was mostly affected by pore structure.
RECOGNITION OF CRUDE OIL TYPES IN THE JURASSIC RESERVOIRS OF CAINAN oil field, THE EAST JUNGGAR BASIN
WANG Chuan-gang, WANG Tie-guan, CHEN Jian-ping, SHI Xin-pu, XIANG Shu-zheng, JIN Tao
2003, 25(2): 183-189. doi: 10.11781/sysydz200302183
Abstract:
Many oil fields including Cainan with reservoirs aged from the Carboniferous to the Jurassic have been found in the East Junggar Basin.Dark mudstones exist in different sags around Cainan oil field,and there hasn't been a conclusion about the oil origin of the Jurassic reservoirs in the area.According to the geochemical characters of stable carbon isotope and biomarkers,oils can be distinguished into five types.Oil of the Jurassic reservoirs in Cainan is conformity,and is characterized the δ13C value of -27.9‰ to -29.0‰ and the Pr/Ph ratio above 2.5,possibly is originated from mixed organic matters of sapropel and humus in lacustine source rocks of the Middle and the Lower Jurassic coal bearing sequence,instead of the mixture of hydrocarbons from different epochs and different facies of source rocks.
OIL AND GAS SURFACE GEOCHEMICAL EXPLORATION IN THE HAIJIAO UPLIFT AND ITS NEIGHBOURING OF THE EAST CHINA SEA
LI Wei-xian
2003, 25(2): 190-196. doi: 10.11781/sysydz200302190
Abstract:
The hydrocarbon geochemical anomalies in the Haijiao Uplift and the Zhejiang Fujian Upfold are the result of upwards seepage of hydrocarbon in the deep pre Cenozoic sedimentary basin.The analytical data of wetness coefficient of acid extracted hydrocarbon of sediment and its δ13 C1 shows that the gas in Qiantang Sag,the Zhoushan Islands and the offshore area around Shanghai are mainly from the thermal cracking of natural gas in deep.They are similar with the gas in Xihu Sag and the Haijiao Uplift which is the over matured gas of deep part.The alkane hydrocarbon abundance index of the gas from Zhejiang Fujian Upfold is higher than that from Pinghu 5 well.
CHARACTERISTIC CONTRAST OF NATURAL GAS WITH MARINE SHALE AND MARL
GAO Gang, WANG Yan-bin, HAN De-xin, CAI Yi, SHI Jun
2003, 25(2): 197-201. doi: 10.11781/sysydz200302197
Abstract:
In this paper,the authors discussed the gas generating characteristics of marine shale and marl by hydropyrolysis.At the mature stage of organic matter,the total gas yield of marl was above that of shale,and their total gaseous hydrocarbon yield was approximately the same.The difference between their total gas yield increased with temperature,and the gaseous hydrocarbon yield of marl was above that of shale at higher temperature.The gas drying coefficient of marl was above that of shale and was below 0.55,and their gas drying coefficient tended to be the same at higher temperature.The normal alkane abundance was higher in shale than in marl,and was stronger than the isonormal alkane,s.Dioxide carbon,nitrogen and hydrogen were major,and oxide carbon was little among nonhydrocarbons.Dioxide carbon content in shale was above that in marl,and hydrogen content in shale was below that in marl.Nitrogen yield was higher at the early and middle mature stage,and was more in marl than in shale.
VISUALIZATION TECHNIQUE OF SOURCE ROCKS PRODUCING HYDROCARBON PROCESS AT HIGH TEMPERATURE BY MEANS OF ENVIRONMENTAL SCANNING ELECTRON MICROSCOPE
YAN Qi-tuan, XIE Zeng-ye, LI Jian
2003, 25(2): 202-205. doi: 10.11781/sysydz200302202
Abstract:
Environmental Scanning Electron Microscope(ESEM)as a new tool has been used in oil and gas research fields.The main advantage of ESEM is to operate under reduced pressure and to allow the observation of samples containing liquid or at high temperature in the microdynamic process.Samples used in this paper were different types of source rocks such as mudstone,carbonate and coal or different organic matter from source rocks such as kerogen and alga.Some samples producing hydrocarbon can be observed.The results indicated that the ESEM test at high temperature was helpful to simulate the process of hydrocarbon producing.
METHOD OF DELAMINATED DECOMPACTION CORRECTION
YANG Qiao, QI Jia-fu
2003, 25(2): 206-210. doi: 10.11781/sysydz200302206
Abstract:
The uniform porosity depth function drawing up on observed data does not express the compaction history of beds because different clastic beds are different in lithology and compaction process in a well or an identical region.The original porosity lied on clastic size and lithofacies so that the original porosity of a sort clastic bed can be considered as the same,but the compaction process could be different from each other.For the sake of reliability of decompaction correction,this paper provides a method of delaminated decompaction correction.First,beds in a well or an identical region are delaminated into some "compaction unit beds" based on their lithology,age,compaction process and so on.Then,the respective porosity depth function which expresses each delaminated "compaction unit bed" needs to be found.The original porosity in the porosity depth function could be determined by modeling sediments.The "compaction model" of delaminated "compaction unit bed" in a well or an identical region could be different or same but it should be reasonable to express their compaction process.And last,using the back strip method computes the paleao thickness and original thickness based on "conversation law of solid thickness of beds".
COMPREHENSIVE PROCESS-ORIENTED SIMULATION OF DIAGENESIS AND ITS APPLICATION
MENG Yuan-lin, WANG Zhi-guo, YANG Jun-sheng, YING Feng-xiang, LIU Yun-hua, LUO Xian-ying, BI Yan-bin, WANG Jia-liang
2003, 25(2): 211-215. doi: 10.11781/sysydz200302211
Abstract:
Based on the process oriented simulation principles of diagenesis in this paper,the effects of temperature,pressure,fluid and time four factors on diagenesis were considered comprehensively.By simulating the vitrinite reflectance of diagenetic parameters,paleogeotemperature,the smectite content in I/S mixed layers,the percentage content of authigenic quartz and the changing rules of sterane isomerization rate in time and space,the diagenetic history of a region was simulated and the spreading characteristics of diagenetic stages were predicted.And according to the controlling action of diagenesis to source rocks,reservoirs and caprocks as well as the matching relation of diagenetic history to tectonic developing history,the favorable exploration districts were determined.At last,the deep layers of Laoyemiao area in the Nanbao Depression of the Bohaiwan Basin were taken as examples to illustrate the application of this method.
ELECTRIC ANALOGY MODELLING EXPERIMENT OF FRACTURE NETWORK RESERVOIR DEVELOPMENT BY HORIZONTAL WELLS
ZHOU De-hua, JIAO Fang-zheng, GE Jia-li
2003, 25(2): 216-220. doi: 10.11781/sysydz200302216
Abstract:
In the light of the complexity of nature fracture networks,it is extremely difficult to do the numerical calculation of fluid flowing and the design optimization of developing well patterns.A series of electric analogy experiments were conducted based on the similarity theory in this paper to model the fracture networks and horizontal well upright well patterns.The relations between fracture networks and horizontal well patterns were studied,and the properties of fracture networks to effect the rate of horizontal wells,such as discreteness,connectivity,density and orientation,were emphasized.As a result,the valuable parameters to optimize horizontal well designing and pressure fracturing for such complicated reservoirs were presented.
FINE SEPARATION OF SATURATED HYDROCARBON AND AROMATIC HYDROCARBON BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY
WANG Hui-tong, YOU Jian-chang, WANG Pei-rong, ZHANG Da-jiang
2003, 25(2): 221-224. doi: 10.11781/sysydz200302221
Abstract:
A method to finely separate saturated hydrocarbon and aromatic hydrocarbon by high performance liquid chromatography(HPLC)was introduced.The oil or bitumen samples were pre prepared by being put in a alumina column,saturated hydrocarbon and aromatic hydrocarbon were eluted together from the column using 90:10 of hexane:ether.After concentrated,the saturated hydrocarbon and aromatic hydrocarbon were ready for further separation by HPLC with the eluent hexane and dichloromethane.The fraction of saturates,monoaromatics,diaromatics and triaromatics would be collected under the control of UV detector and fraction collector.Compared with the method from abroad,the advantages of our method are visible:reagent and time saving.