2006 Vol. 28, No. 4

Display Method:
TECTONIC EVOLUTION AND PETROLEUM PROSPECTION IN THE YIN’GEN-EJINA BASIN
Chen Qilin, Wei Pingsheng, Yang Zhanlong
2006, 28(4): 311-315. doi: 10.11781/sysydz200604311
Abstract:
The basement formed by plates and sutural zones apparently controls the evolution of Yin'gen-Ejina Basins.The tectonic evolution has undergone 5 stages: heat-upheaval and tension-crack stage of the Early Triassic,rudiment rift basin stage of the Early-Middle Jurassic,stretch faulting stage of the Early Cretaceous,relaxation depression stage of the Late Cretaceous and inland convergence stage of Tertiary.Different tectonic stages result in different trap styles.Hydrocarbon source rocks of the Lower-Middle Jurassic and the Lower Cretaceous form source and reservoir.The exploration realms of half graben-like basin are fault noses and fault block traps in the central fracture and ridgy zones,and litho-(logic) traps and stratigraphic unconformity traps in the gentle slope zones.The exploration realm of downfaulted basin is roll anticline in the fracture zones controlling basin.A new notion of source nearby exploration around sub-depression in little lacustrine basins are proposed.
GEODYNAMIC TYPES AND MECHANISMS OF TRANSPRESSIONAL BASINS
Xiang Kui, Shi Huaxing, Yang Pinrong
2006, 28(4): 316-321. doi: 10.11781/sysydz200604316
Abstract:
The transpressional basin is not only one of the widespread basin types but also an important petroliferous basin type in the world.A reasonable classification and the discussion of formation mechanism of transpressional basins will be helpful for petroleum geology study and exploration potential evaluation.Based on the study of basin structure and hydrocarbon exploration,it is put forward in this paper a basic classification scheme of the transpressional basins.According to transpression time and its relation to basin formation,the transpressional basins can be basically classified into the proto-and the post-transpressional ones.Then,according to plate tectonic settings,transpression mechanism and transpressional force magnitude,the transpressional basins can be further classified into many secondary types.Based on the geodynamic settings of transpressional basins,it is analyzed in this paper their formation mechanisms and structural features.The tectonic background of transpressional basins is quite different from which of the extensional or trans-extensional basins.The transpressional basin has been predominantly resulted from oblique compression,such as oblique compression plate boundary,transform plate boundary and the peripheral area of collisional orogens.The formation mechanism of post-transpressional basin is much more complicated than that of the proto-transpressional basin.The oblique-compression between plates,the accretion of micro-terranes,and the plate rotation,etc.can accordingly give rise to the formation of transpressional basin.
TECTONIC DEFORMATION OF FORELAND BASIN IN THE NORTHERN PART OF LOWER YANGTZE AREA
He Mingxi, Du Jianbo, Gu Zhe, Xie Qifeng, Ma Rongfang, Zhang Dongmei
2006, 28(4): 322-324. doi: 10.11781/sysydz200604322
Abstract:
Owing to the tectonic deformations during the Indosinian,Yanshan and Xishan epochs,the tectonic environment of foreland basin in the northern edge of lower Yangtze area changes from rift,collision matching to stretch rift,and ultimately results in a structural geometrical model of "3 tiers pavilion" with stretch in the top,thrust nappe in the middle and decoupling slip in the bottom.The tectonic deformation is mainly controlled by the collision orogenesis of Yangtze and North China platforms during the Middle Triassic with the characteristics of strong-weakness zoning horizontally and deformation layering vertically.The deformation style includes 3 types: stretching deformation,thrust fold deformation and decoupling slip deformation.
GENERATION ENVIRONMENT OF COAL MEASURE SOURCE ROCK IN THE EAST OF JIYANG AND LINQING, THE BOHAIWAN BASIN
Wang Guoshou, Miu Jiujun, Lu Jianlin, Xiao Huanqin, Zhang Xinguo
2006, 28(4): 325-329. doi: 10.11781/sysydz200604325
Abstract:
Drilling,seismic,logging and testing data have indicated that,Carboniferous and Permian in the east of Jiyang and Linqing in the Bohaiwan Basin are mainly composed of a set of neritic carbonate platform facies limestone as well as barrier-lagoon,tidal flat,paludal and deltaic facies terrigenous clastic rock and coal bed.Vertically,in the Benxi Formation of the Upper Carboniferous,neritic carbonate platform facies carbonate rock and neritic continental shelf facies sand/mud stone are generated.In the Taiyuan Formation,a combination of barrier-lagoon,tidal flat,paludal facies carbonate rock,terrigenous clastic rock and coal bed is deposited.In the Shanxi Formation of Permian,deltaic facies and deltaic plane paludal facies sand/mud stone as well as coal are generated.In the Lower and Upper Shihezi Formation,offshore continental facies clastic rock is deposited,and in some places are fluvial paludal peat and coal generated.Sedimentary environment changes from neritic facies,marine/continental facies to continental facies,from bottom to top,south to north.The tidal flat,paludal and the deltaic plane paludal environments during the Taiyuan and Shanxi periods are most favorable for coal generation.
RESERVOIR CHARACTERISTICS IN THE SE UPLIFT, THE SOUTH OF SONGLIAO BASIN
Yang Minghui, Guo Li, Zhao Hongtao, Shi Yali, Zhang Kun
2006, 28(4): 330-334. doi: 10.11781/sysydz200604330
Abstract:
Four types of reservoir have been generated deep in the SE uplift,the south of Songliao Basin.The previous studies have indicated that,sandstone and glutinite are the major reservoirs.The rocks in different faults are mainly detritus feldspar sandstone and feldspar detritus sandstone.Strong diagenesis changes reservoir ability to different extents.Due to the influence of various factors,three induced porosity zones,which have improved the storing ability of reservoir to different extents,have been developed in the reservoirs of sandstone and glutinite located in the southeast deep layer.It can be concluded through comprehensive evaluation that,the physical performance of reservoir bed in the first part of Quantou Formation in various faults is relatively better and it should be the major objective layer in future exploration.Physical performance of all layers in the Wangfu fault is relatively worse.
THE RELATIONSHIP BETWEEN FAULTS AND OIL-GAS MIGRATION AND RESERVOIRING IN THE SOUTHEASTERN UPLIFT OF THE SONGLIAO BASIN
Wang Dehai, Guo Feng, Ren Guoxuan, Meng Xianghua, Yang Xigui
2006, 28(4): 335-339. doi: 10.11781/sysydz200604335
Abstract:
The southeastern uplift of Songliao Basin has been reconstructed for several times by tectonization,and formed complex fault system.Based on the characters,scale,forming time and space of the fault and its relationship with oil and gas,fault system can be divide into three types: early-fault,late-fault and early fault of later moved.Fault-controlled basin controlled the forming and evolution of the faulted sag,and fault-controlled sediment controlled the distribution of the better source rocks.Faults cannot be favorable in oil and gas migration when they are stopped moved,otherwise oil and gas can migrate vertically.Fault reservoir can be formed when its above slope possess impervious formation.Early-faults aren't migration for oil and gas,so early primary oil and gas accumulation formed in source rocks with better preservation.Traps often destroyed by early-fault and resulted in complexity and discontinuous of the oil and gas distribution.Late-faults and early-faults of later moved are favorable vertical migrated channels,meanwhile,the faults destroyed the primary oil and gas accumulation and lead to remnant oil and gas accumulation in shallow strata.Late-faults aren't lengthways for oil and gas migration when they are stopped moved.So late primary oil and gas accumulation can be formed with better reservation.The relationship between faults activity stage and hydrocarbon expulsive stage controlled the distribution,forming and destroy of oil and gas accumulation.
PATHWAY SYSTEM TYPES AND HYDROCARBON ACCUMULATION IN BACHU AREA, THE TARIM BASIN
Yin Wei, Fan Tailiang, Zeng Qingbo
2006, 28(4): 340-344. doi: 10.11781/sysydz200604340
Abstract:
The pathway system is classified into 3 types of fault,carrier bed and unconformity in Bachu area,the Tarim Basin.First,it is analyzed the formation and migration ability of single pathway system.However,the single pathway system is not common under certain geologic condition,hence it is put forward the combination pathway system.It is an efficient hydrocarbon migration network.The classification and the migration ability of combination pathway system are changing.Consequently,only that the diversified types of pathway system are placed in their suitable locations temporally and spatially,can hydrocarbon accumulation be promoted.
OVERPRESSURE CHARACTERISTICS IN THE JIYANG DEPRESSION, THE BOHAIWAN BASIN
Xu Xiaoming, Liu zhen, Xie Qichao, Zhang Shanwen, Zhao Yang, Cai Jingong
2006, 28(4): 345-349. doi: 10.11781/sysydz200604345
Abstract(1034) PDF-CN(321)
Abstract:
Pressure evolution is controlled by geologic conditions.The Dongying and Zhanhua Sags of the Jiyang Depression in the Bohaiwan Basin are similar in tectonic characteristics and evolution,over-pressure vertical distribution,main distribution strata and origin mechanism,so their pressure evolutions also have some similarities.The Bonan sub-Sag is a typical overpressure sub-sag in the Zhanhua Sag of the Jiyang Depression.Based on quantitative analysis of pressure field evolution,it is discovered that overpressure in the Bonan sub-Sag developed late.The main strata of overpressure(the third member and the upper part of the fourth member of Shahejie Formation) developed after the Dongying episode.Overpressure in the whole Jiyang Depression developed late.
STUDY ON ORGANIC MATTER’S MATURATION AND HYDROCARBON-GENERATING HISTORY IN THE QIANGTANG BASIN
Qin Jianzhong
2006, 28(4): 350-358. doi: 10.11781/sysydz200604350
Abstract:
Researches on the analytical data more than seven thousands of Mesozoic samples from the Qiangtang Basin in Qinghai-Tibet Plateau show that the Jurassic source rock is still mature and generating oil in the center of Qiangtang Basin.The Jurassic source rock is more and more mature from the center to the margin of the basin.Almost all the T3x source rocks are high-mature to over-mature and the range of oil generation has already very small.The maturity of the organic matters in this basin is mainlly controlled by the palaeo-geotemperature,the degree of tectonic deformation and pyrogenetic rock and plutonic hot fluid.In the center and the east of the basin,the main influential factor of organic matter's maturation is the maximum palaeo-geotemperture or palaeoburial depth.Near the fault or folded zone in the basin and the margin of the basin,organic matter's maturation is mainlly affected by the strongly unbalanced pressure.And in the west of the basin,the plutonic hot fluid in the basement fracture zone may be the main influence factor of organic matter's maturation.There are two (or three) hydrocarbon-generating processes occurring in the Late Jurassic-Early Cretaceous and the time of Tertiary sedimenting.In particular,the hydrocarbon-generating process caused by the Jurassic source rock in the Early Miocene to the Late Miocene is more favorable to the petroleum exploration in this basin.
HIGH-QUALITY SOURCE ROCKS IN THE LOWER COMBINATION IN SOUTHEAST UPPER-YANGTZE AREA AND THEIR HYDROCARBON GENERATING POTENTIAL
Tenger, Gao Changlin, Hu Kai, Pan Wenlei, Zhang Changjiang, Fang Chengming, Cao Qinggu
2006, 28(4): 359-365. doi: 10.11781/sysydz200604359
Abstract:
There are good oil and gas exploration prospect in the southeast of Upper-Yangtze area,but the geologic conditions are complicated and the degree of exploration is low there.The potential hydrocarbon source rocks in Xianfeng and Dayong areas were studied to determine the characteristics of their organic geochemistry,petrology,carbon isotope composition and thermal evolution,etc.Two series of high-quality hydrocarbon source rocks were discovered.They are the Lower Cambrian black shale and the Upper Ordovician Wufeng Formation-Lower Silurian Longmaxi Formation black shale in the Lower Palaeozoic.Both of them have characteristics as follows: 1)good organic types(sapropel type),high abundance of organic materials and hydrocarbon potentials;2)large thickness and extensive distribution;3)good hydrocarbon generating potential and evidences of oil(bitumen) and gas.At the Late Jurassic-Cretaceous,the thermal evolution degree of the hydrocarbon source rock in the Lower Cambrian has come to the early stage of over-mature at which the dry gas was generated.And the hydrocarbon source rock in the Upper Ordovician-Lower Silurian has come into the late stage of high-mature to the early stage of over-mature,which was the peak period of gas generation.These high-quality hydrocarbon source rocks provide abundant organic material basis for the hydrocarbon generation and accumulation in the Lower Combination in the west of Hunan and Hubei,the east of Chongqing and the Xuefengshan nappe zone.
STUDY OF PETROLEUM MIGRATION OF THE SILURIAN ANCIENT POOLS AROUND AWATI SAG IN THE TARIM BASIN USING CARBAZOLE COMPOUNDS
Liu Luofu, Huo Hong, Li Chao, Zhao Suping, Chen Yuanzhuang, Chen Lixin, Guo Yongqiang, Li Yan, Li Shuangwen
2006, 28(4): 366-369. doi: 10.11781/sysydz200604366
Abstract:
Carbazoles are polar compounds in oils,and they are useful indicators for study of hydrocarbon migration.In oil migration,carbazoles have effects with and can be adsorbed to country rocks;Benzo[a]carbazole migrates faster than benzo[c]carbazole;C3-carbazole has smaller polarity than C2-carbazole and the former can migrates faster.Therefore,with increasing the migrating distance,amount of carbazole in oil decreases,Benzo[a]carbazole/ benzo[c]carbazole ratio increases,and C2-carbazole/C3-carbazole value reduces.The second period of hydrocarbon reservoir formation in the Tarim Basin took place in later Hercynian.In Hercynian,the Awati Sag kept subsiding,and it was the major hydrocarbon-generating sag in the Tarim Basin.At that time,the Cambrian-lower Ordovician source rocks in the Awati sag were in the phase of large-scale hydrocarbon expulsion,and based on the above-mentioned indices of nitrogen compounds,the expelled hydrocarbons migrated in all directions from the hydrocarbon generation center and were trapped in structural highs.These hydrocarbon pools rose to the surface in the end of Hercynian and the hydrocarbons formed widely distributed dry asphalts.
CHARACTERISTICS AND SIGNIFICANCES OF HYDROCARBON SHOWS IN THE NIQIUJI SAG, THE SOUTHERN NORTH CHINA BASIN
Quan Yuke, Liu Guangdi, Ding Wenlong
2006, 28(4): 370-374. doi: 10.11781/sysydz200604370
Abstract:
There are 16 exploration wells drilled in the Niqiuji Sag,the Southern North China Basin and 7wells of them have obtained hydrocarbon shows.The Well Nan 12 located in Dawangzhuang structure is an industrial discovery well with producing commercial crude oil of 32.26 m3s in well testing.In this article,statistics of the oil and gas shows was made and the conclusions have obtained as follows: the oil and gas shows occur mainly in Shuangfu Formation in Paleogene,the predominant reservoir rocks are medium-grained and fine-grained sandstones,oil shows occur mainly in the depths of 1 000 to 2 000 meters and gas shows occur mainly in the depths of 3 000 to 4 000 meters,the crude oil is characteristic of coal-derived oil and has undergone biodegradation and water-washing.The above conclusions suggest that there is at least one epoch of petroleum formation,migration and accumulation in Niqiuji depression.The preliminary conclusions for exploration orientation include that both primary and secondary pool are the exploration targets,the Upper Cretaceous is a disadvantageous factor for petroleum accumulation because it may be a barrier of vertical petroleum migration from the source rocks in CarboniferousPermain to the reservoirs in the Paleogene.
STUDY ON ORGANIC MATTERS IN THE SEDIMENTS FROM THE BOTTOM OF THE QINGHAI LAKE, CHINA
Li Shanying, Yu Bingsong, Dong Hailiang
2006, 28(4): 375-379. doi: 10.11781/sysydz200604375
Abstract:
Saline lake is one of the most favorable environments for developing hydrocarbon source rocks.Analyzing the group components and the saturate hydrocarbons in organic matters in the sediments from the bottom of the Qinghai Lake shows that the contents of total organic carbon in the sediments is high and that the sedimentary environment at the bottom of the Qinghai Lake is feeble oxidative.The organic matters mainly originate from the higher terrigenous plants around the Lake and the microbes and algaes in the Lake.Comparing the parameters such as distribution of carbon amount,carbon amount with peak value of content,carbon predominance index(CPI),and pristane/phytane ratio(Pr/Ph) in the immature organic matters in the sediments from the bottom of Qinghai Lake with those in mature hydrocarbon source rocks and crude oils from the typical salty lacustrine environment in our country can give us a set of valuable reference data about the maturity of organic matters.
GEOCHEMICAL CHARACTERISTICS AND SOURCE OF MIDDLE JURASSIC OIL FROM GUANDU STRUCTURE IN THE SOUTHEASTERN SICHUAN BASIN
Cai Xunyu, Zhu Yangming
2006, 28(4): 380-385. doi: 10.11781/sysydz200604380
Abstract:
Based on the systematic analytical data of light hydrocarbon,saturate,aromatic fractions and carbon isotopes,the geochemical characteristics of Middle Jurassic oil from Guandu structure in the southeastern Sichuan Basin was investigated,and the source rock for the oil was determined by oil/ source rock correlation.The studied results reveal the oil shows a dominance of n-alkanes,low amount of branched/cyclic hydrocarbon and a lack of benzene and toluene with a predominance of heptane over methylcyclohexane in C5-C8 light hydrocarbons.Its relative low Pr/Ph (1.56),"V" shaped distribution of C27-C29 steranes and enhanced gammacerane indicate a profundal lacustrine source rock with relatively high contribution of aquatic organisms to deposited original organic matter The studied oil exhibits common features for a terrestrial oil,as reflected by its waxy n-alkane distribution and the isotope profile showing a trend toward isotopically light values with increasing n-alkane chain length.According to the correlations based on the parameters of light hydrocarbon and biomarkers,the oil is believed to be not in origin associated with the natural gas and asphalts in Xujiahe stratum (Upper Triassic),and is determined to be derived from Lower Jurassic source rock.
NEW APPROACH TO DISCRIMINATE OIL FLUID INCLUSIONS QUICKLY——QUANTITATIVE GRAIN FLUORE SCENCE(QGF)TECHNIQUES AND ITS APPLICATION
Li Sumei, Pang Xiongqi, Liu Keyu, Fu Xiuli
2006, 28(4): 386-390. doi: 10.11781/sysydz200604386
Abstract:
A new approach utilizing fluorescence scanning technique to analyze adsorbed hydrocarbons and non-hydrocarbons,identify oil inclusion and fluorescence fingerprint was introduced,and the Hailaer Basin was selected as a case study.Totally 18 samples collected mainly from Mesozoic clastic rock reservoir from the basin were chosen to perform QGF-E (Quantitative Grain Fluorescence on Extract) and QGF (Quantitative Grain Fluorescence)analysis.It was proved that the experimental procedure of QGF-E and QGF analysis is a simple,quick and low cost way.The results of QGF-E showed that the intervals where the samples were collected were once to be pathways of oil migration and/or transited carrying bed of hydrocarbons.The results of QGF indicated that only a little oil inclusions were formed in the reservoir analyzed for some reasons.This study suggests that QGF-E and QGF are able to readily delineate current and paleo-oil column,oil migration pathway,current oil-water and residual oil-water contacts as well as identifying existence of oil inclusions,which would be helpful in reconstructing process of hydrocarbons accumulation.
THE STUDY OF FLUID INCLUSIONS IN JURASSIC OF THE SANTANGHU BASIN
Hao Jianrong, Liu Yiqun, Cao Qing, Xing Xiujuan
2006, 28(4): 391-394. doi: 10.11781/sysydz200604391
Abstract:
Chosing the Santanghu Basin in Xinjiang as an example,according to secondary fluid inclusions' facieology,salinity,homogeny temperature and character of associated hydrocarbon fluid inclusions in Jurassic reservoir,it is believed that the inclusions in the crack of quartz have formed at different fluids process and of different periods combining with the study of thermal evolution of the basin.The analysis show that there exist a heat event at the end of Jurassic,migrating by cracks from the deep stratum.Accordingly,the fluid inclusions have great significance in analyzing of the information about hydrocarbon migration,at the same time,it can provide heat events in geological history.The fluid inclusions bear the characteristics of multi-origin and multi-period,which are critical in studying the thermal and maturity history of hydrocarbon source rocks in basin.
STUDY ON THE DISTRIBUTION OF THE MICRO-FRACTURES BY ANN——TAKING THE CA OILFIELD IN GAOYOU SAGIN THE NORTH JIANGSU BASIN AS AN EXAMPLE
Wang Jiayue, Yan Hong, Ao Lide, Qu Hong
2006, 28(4): 395-398. doi: 10.11781/sysydz200604395
Abstract:
There are many micro-fractures in the CA Oilfield in Gaoyou Sag,the North Jiangsu Basin.The aperture and extension length of these micro-fractures are too small to identify easily.The methods and means being used to study are limited.Based on the acoustic logging curve,the microinverse,the micronormal,the 6 m electric resistance curve and the resistivity curve in flushing zone,the 3D mathematical model about the distribution of the micro-fractures in this area can be established by using the method of artificial neural network.In this paper,the micro-fracture parameters were predicted by this way.The predict result was verified by the dynamic data analysis.It is reliable to predict the distribution of micro-fractures by using the mathod of artificial neural network.
TROUBLE RESERVE OPTIMAL LIMIT AND DEVELOPMENT DESIGN PLAN FOR FUYANG OIL LAYER, DAQING OILFIELD
Zhou Yongbing, Cui Baowen, Zhou Xisheng
2006, 28(4): 399-403. doi: 10.11781/sysydz200604399
Abstract:
TROUBLE RESERVE OPTIMAL LIMIT AND DEVELOPMENT DESIGN PLAN FOR FUYANG OIL LAYER, DAQING OILFIELD
THE HETEROGENEITY MODEL OF LOW PERMEABILITY RESERVOIR AND REMAINING OIL DISTRIBUTION——A CASE STUDY OF DUJIATAI OIL ZONE IN QI 9-HUAN 50 BLOCK, THE WEST LIAOHE DEPRESSION
Li Hongnan, Xu Huaimin, Xu Ning, Huang Shiyan
2006, 28(4): 404-408. doi: 10.11781/sysydz200604404
Abstract:
Three macro-heterogeneity models of reservoir,interbedded,intraformational and planar,has been established for the Dujiatai reservoirs in Qi 9-Huan 50 Block in the West Liaohe Depression based on the dynamic and static data.And the distribution principle of remaining oil for low permeability(reservoirs) in the front of fan delta facies has been revealed.Moreover,the effect of macro-heterogeneity on forming and distribution of remaining oil has been discussed.Research shows that the macro-heterogeneity of this set of reservoir beds is apparent,that the vertical distribution of remaining oil within oil zones is controlled by interbedded and intraformational anisotropism and that the planar distribution is controlled by planar and intraformational anisotropism.