1997 Vol. 19, No. 4

Display Method:
SIMILARITIES BETWEEN CENOZOIC BASINS OF DIFFERENT MAGNITUDES IN EAST ASIA CONTINENTAL MARGIN
Xu Junyuan
1997, 19(4): 297-304. doi: 10.11781/sysydz199704297
Abstract:
The Cenozoic basins of different magnitudes in East Asia continental margins are similar and self similar in shape.They are para-rhomb,preferentially delimited by NNE and NEE as well as EW tending faults.During formation,they had similar kinematics with their bilateral blocks being pulled apart in nearly NSdirection;they were also characteristic of similar geodynamics,and the regional minimum main stress trajectories had been oriented nearly NS,which has resulted from collision between Eurosia plate and indianplate,and dextral shearing along the boundary between Eurosia and Pacific plate.Many tectonic phenomena in Cenozoic basins of East Asian continental margins can not be explained by the current theory of"Collision-Extrusion Tectonics".
TOPOGRAPHIC EXPRESSION OF SUBSURFACE STRUCTURES AND ITS APPLICATION IN PETROLEUM EXPLORATION
Dang Zhenrong
1997, 19(4): 305-311. doi: 10.11781/sysydz199704305
Abstract:
East China oil province,with block faulting as its main structural expression,consists of Bohai Wan basin and Mongolia-Xingan rift basins,whose subsurface structures usually show good topographic expresstion.The differential compaction due to the relief of basin base and thickness change in young cover rocks,and long development of inherited structures result in an internal relation necessary between the subsurface structures and their topographic expression.Thus the information of topographic expression is useful for the explanation of subsurface structure.There are vivid examples of petroleum exploration success with the application of topograpI1ic information both home and abroad.Its application is particularly significant in a preliminary petroliferous estimation in a basin(or a depression or sag)during the preparation of a back-up campaign of exploration.Topographic informaiton can be used to ascertain the plane spreading scale and size of a basin,further to determine the linear geologic structures of the basin,including classes I II major faults,oil-generating depressed trough,structural belts as well as local structures,and to analyse sedimentary facies.Undoubtedly,it may be helpful for making a precise strategic policy and plan of petroleum exploration,and determination of working and financial amounts,and for a higher rate of exploration success.
PROSPECT FOR EXPLORATION TARGETS IN SMALL—MEDIUM JURA—CRETACEOUS BASINS, NORTH CHINA
Fah Xiaolin
1997, 19(4): 312-316. doi: 10.11781/sysydz199704312
Abstract:
In the north China intraplate,Jura-Cretaceous basins could occur in a form of either an extensionalfaulted or depressed basin in synrifting(or post-rifting)or strike-slip foreland,or a strike-slip pull apartbasin during synorogeny(or post orogeny),whose formation was controlled by Mesozoic tectonic movements.Corresponding to a warm and humic paleo-climate,limnetic sediments were developed in the basin,which became basins' material basis.The relative late intraplate orogeny caused the expulsion,migration,and accumulation of hydrocarbons,which were entrapped to form into the petroleum structural belts discovered up to now.In such a basin,the reservoir assemblages consist of Jura-Cretaceous strata and thestructural traps(pop-up anticline,fault block flexure or block fault-rolling anticline)on relative upliftedor lowly embossed parts close to the down-warping source region should be regarded as petroleum exploration targets.
A PRELIMINARY APPROACH TO FAULT—PLANE STRUCTURAL SYSTEM AND ITS SIGNIFICANCE OF PETROLEUM GEOLOGY—EXEMPLIFIED BY WANGJIAGANG OIL FIELD IN DONGYING DEPRESSION
Chen Buke, Liu Jiaduo, Du Xianyue, Wang Xinzheng
1997, 19(4): 317-322. doi: 10.11781/sysydz199704317
Abstract:
The paper proposed a new concept of fault-plane structural system,taking Wangjiagang oilfield for an example.Based on a detailed description of the characteristics of fault-plane structural systems,their shielding capability for oil and gas is studied,and then the sealing properties on different parts of different fault planes are appreciated.The paper also approached to the role of a fault-plane structural system on oil and gas enrichment,and suggested that "planar anticline" and "planar nose" fault-plane traps are new areas of oil/gas exploration.
ANALYSIS OF STRUCTURAL STYLES AND RESERVOIR—FORMING CONDITIONS IN EASTERN LINQING DEPRESSION
Song Guoqi, Liu Zhongquan
1997, 19(4): 323-327. doi: 10.11781/sysydz199704323
Abstract:
From the point of view of the data about the formation and evolution of the basin,the paper discussedthe structural styles in eastern Linqing depression.Altogether 7 types of structural styles and their superposition related to hydrocarbon accumulation were identified in the half-graben,along with an approach totheir genetic mechanism and distributive features.Finally the paper proposed the favourable explorationtargets in the region,after an analysis of the accumulative characteristics of hydrocarbons,on the basis ofthe conditions of source,reservoir and cover.
PRELIMINARY INVESTIGATION ON THE FORMATION MECHANISM OF SILURIAN RESERVOIR IN TAZHONG LOW—UPLIFT OF TARIM BASIN
Lu Xiuxiang
1997, 19(4): 328-331. doi: 10.11781/sysydz199704328
Abstract:
Tazhong low-uplift is an early Paleozoic remnant paleo-uplift,which was formed during the late Caledonian period on the background of the sedimentary uplift developed during the early Caledonian period.The Silurian asphalt sandstones extensive in the area were formed in the process of petroleum migrationand accumulation rather than after reservoir formation.The entrapment of hydrocarbons by the Siluriansandstones experienced a complicated process of accumulation,destruction and reaccumulation.Thefavourable petroleum accumulation area in the Silurian considered as target bed is the plunging part innorthwestern Tazhong low-uplift.
MARINE HYDROCARBON GEOCHEMICAL PROSPECTING—WITH A STUDY AREA IN EAST CHINA SEA AS AN EXAMPLE
Zhang Jianpei, Wang Fei
1997, 19(4): 332-336. doi: 10.11781/sysydz199704332
Abstract:
Marine hydrocarbon geochemical prospecting is one of important methods often used in marine hydrocarbon survey.By analysing one of successful examples of geochemical prospecting in East China Sea,thepaper illustrated the techniques and effects of their application involved in marine hydrocarbon geochemicalprospectings.
STUDY OF VOLCANIC ROCK RESERVOIRS—FROM BEIBAO AREA OF NANBAO SAG
Guo Qijun, Wan Zhimin, Jiao Shouquan, Liu Laixiang, Liu Yunhua, Cao Zhonghong
1997, 19(4): 337-339. doi: 10.11781/sysydz199704337
Abstract:
Volcanic rock,as one of non-conventional reservoirs,became more and more significant because of theincreasing discoveries of industrial oil/gas pools are made within and outside the country,which is drawinga great attention of petroleum geologists.China also starts to carry out a systematic study on this aspect.The paper is a study of volcanic rock reservoirs,the lithological characteristics and properties that affect on the capability of volcanic rock reservoirs,with Beibao area of Nanbao sag taken as an example.Finally the influential factors on the variation of reservoirs of the srudy area are concluded.
SEQUENCE STRATIGRAPHY AND OIL—GAS ACCUMULATION REGULAR PATTERN AROUND THE WESTERN SLOPE IN SOUTHERN SONGLIAO BASIN
Guo Shaobin
1997, 19(4): 340-343. doi: 10.11781/sysydz199704340
Abstract:
Based on the detailed study on the current situation of non-marine sequence stratigraphy research,theauthor proposed a complete uprising-depressing cycle on a horizontal plane that can form four systemtracts,i.e.lowstand,lake extension,highstand,and lake contraction system tracts,with the western slopein the southern sector of Songliao basin(WSSB)taken as an example.As for an incomplete cycle,the temporal and spatial evolution of the system tracts is expressed as lowstand,lake extension,and highstand or aslake extension,highstand and lake contraction system tracts.Finally,the oil-gas accumulation patternaround the southwest slope of Songliao Basin is concluded.
DISTRIBUTION CHARACTERISTICS OF FRACTURES IN LOW PERMEABLE RESERVOIRS IN AN EXTENSIONAL STRUCTURAL REGION
Zeng Lianbo, Tian Chonglu
1997, 19(4): 344-347. doi: 10.11781/sysydz1997043344
Abstract:
The dolomite reservoir of Sha 4 Member in Leijia Formation,Liaohe basin is taken as an example to study the distribution characteristics of fractures in low permeable reservoirs of an extensional structural region.Three distributive types of fractures are identified,i.e.internal,transverse and bedding fractures,of which internal fracture is strictly controlled by dolomites,perpendicular to and terminated onto the bedding plane;whereas transverse fracture is in a high-angle oblique to bedding plane.On a section,a mono-fracture appears planar,listric and ramp-flat;and multi-fractures may be in a combined pattern of grabenuhorst or domino,showing a consistent distribution with the growth normal faults in the region.Fractures and normal faults will constitute a complete structural style of an extensional structure within the region,ranging from macroscope to microscope in scale.The distribution of fractures in a reservoir is controlled by the factors of lithology,bed thickness and faults,etc.Transverse and bedding fractures are well developed in the argillaceous interlayers of dolomlte reservoirs,and are interconnected;together with fractures in the dolomites,they make up a 3-D fracture network.As a result,the argillaceous interlayers can not be taken as impermeable layers but para-reser-voirs instead,and thus the dolomite oil reservoirs are characteristic of block.Toward an extensional fault,the fractures in the lianging wall are more developed than those in the footwall with good zonation.
SEQUENCE STRATIGRAPHIC ANALYSIS ON UPPER PERMIAN HESHAN FORMATION IN HESHAN AND LAIBIN AREAS IN CENTRAL GUANGXI
Wang Genfa, Huang Fengming, Huang Naihe, Weng Xi
1997, 19(4): 348-353. doi: 10.11781/sysydz199704348
Abstract:
The present paper analyzes the upper Permian Heshan Formation from Heshan and Laibin areas incentral Guangxi by employing the study methods of outcrop sequence stratigraphy.In the Heshan Formation,7 sequence boundaries and 6 sequences defined by the boundaries are recognized.Among the 6 sequences,5 are attributed to type Ⅰ,and I to type Ⅱ.The sequences were formed in passive continentalmargin environment.Platform area was dominated by the sedimentation of the shallow carbonate sediments,and in the basin area the sediment of deep silicalite was developed in under-compensated conditions.
RESERVOIR TRANSVERSE PREDICTION BY SEISMOLOGY FOR EOGENE IN YM 7—9 WELLS REGION
Zhang Chunsheng
1997, 19(4): 354-358. doi: 10.11781/sysydz199704354
Abstract:
The method of reservoir transverse prediction is inexpensive and effective,which is often used to makea preliminary study on a reservoir in the case of few wells available,using seismic data in combination oflogging and geological information.The paper uses 2-D and 3-D seismic data to predict the distributioncharacteristics,thickness,porosity,permeability and oil saturation of Eogene bottom sandstones in YM 7-9 wells region.The results are satisfactory.The key to a reservoir prediction by seismics is a precise demarcation of the horizon and making a PIVT section.
APPLICATION OF ARC/INFO AND ARC VIEW IN PETROLEUM GEOLOGY
Zeng Yi, Jin Qiang, Liang Hong
1997, 19(4): 359-362. doi: 10.11781/sysydz199704359
Abstract:
This paper introduces softwares of the ARC/INFO and Arc View into integrated research of petroleum geology,and discusses their functions and methods of the input,edit and macro-mappong on petroleum exploration and development data.The authors suggest that the ARC/INFO and Arc View will become the main softwares in study of petroleum geology,because the softwares improve greatly the efficiency and precision of integrated analysis of petroleum geology.
PROPERTIES OF RESERVOIR ROCKS IN DUJIATAI OIL FORMATION, BLOCK HUAN 50, WESTERN LIAOHE DEPRESSION
Chen Heping, Yang Zhouping, Gao Jie, Guo Jianhua
1997, 19(4): 363-367. doi: 10.11781/sysydz199704363
Abstract:
The reservoir sandbody of Dujiatai oil formation in the study area can be genetically attributed to anear-sourced and rapidly accumulated fan delta.The main types of reservoir rocks include fine gravelstone,inequigranular sandstone,sandstone and siltstone.Different types of rocks differ significantly inphysical properties.The analytical results of rocks with such a genesis can be middle-low permeabilityreservoirs,and there exists a certain correlative relation among their lithologic characteristics,physicalproperties,electricity and oil potentials;moreover,a direct correlation between porosity and permeabilityis recognized.Obviously the distribution of the reservoir rocks are controlled by sedimentary microfacies.
FRACTURE CHARACTERS OF MIDDLE—UPPER JURASSIC RESERVOIRS IN NORTHERN TURPAN—HAMI BASINS
Liu Linyu, Liu Yiqun
1997, 19(4): 368-370. doi: 10.11781/sysydz199704368
Abstract:
The paper approaches the fracture characters of middle-upper Jurassic reservoirs in northern Turpan-Hami basin,based on the analyses of the data from cast thin sections and scanning electron microscopicobservations,It is considered that the fractures were formed in four different stages(times),and basicallycan be classified into five types.Fracture is one of essential factors that would improve reservoir properties.
SEISMOLOGIC PREDICTION OF THERMAL MATURITY OF LOWER CRETACEOUS IN HONGHOLSHUT DEPRESSION
Liu Zheng, Sun Qiang, Wu Yaohui
1997, 19(4): 371-376. doi: 10.11781/sysydz199704371
Abstract:
There is a close relation between the porosity and vitrinite reflectance(Ro)of kerogen in the mudstones of Bayanhua Group,lower Cretaceous in Hongholshut depression.By a correlation,it is found thatthe relation between the porosity and vitrinite reflectance is most closely approximating to a power function.Based on this power functional relation,porosity was converted from the seismic velocity of mudstones,then the vitrinite reflectance was calculated from the porosity,finally to delineate the immatureand mature areas for the main hydrocarbon source rocks in the sag,and provide evidences for the selectionof near-source targets.The method that measures organic thermal maturity directly from seismic information is of great value for areas with lower exploratory levels,especially for the basins with sparse welldrillings.
GEOCHEMICAL PROPERTIES OF CRUDE OIL IN ZANG 1 WELL, LUPOLA BASIN, NORTHERN TIBET
Lu Yaping, Shao Zhibing, Bai Senshu
1997, 19(4): 377-381. doi: 10.11781/sysydz199704377
Abstract(1192) PDF-CN(287)
Abstract:
Zang 1 Well is the well where the first commercial oil and gas discovery in Lupola basin was located.Geochemical study shows that its crude oil is essentially conventional oil characteristic of high wax and low sulfur;chemically it is classified as intermediate aromatics;and its source materials include alga and higher plants,ranging from sapropelic to humic-sapropelic types;its orlginal depositional environment is salt lake basin- Basically the evolution of crude oil reaches to low-mature stages;and waterwashing and oxidation with a relative weak biodegradation are considered as the main epigeneses.
SEQUENTIAL ANALYSIS OF BLACKSHALES AND ITS APPLICATION TO BIOMINERALIZATION RESEARCH
Wang Pujun, Chang Ping, Li Hong, Wang Dongpo
1997, 19(4): 382-387. doi: 10.11781/sysydz199704382
Abstract:
After leaching blackshales with CHCL3,HaAc-NaAc buffer,HCl-H3PO4 mixture,HCl-HP mix-ture and heavy liquid sequentially,chloroform extracted bitumen-A,carbonate,ferromanganese oxide,silicate components and kerogen are obtained respectively-The recovery of standard addition for different components ranges 86%-104.3%.The sequential analysis is applicable to,besides the study of main components in oil shales,biomineralization research.
1997, 19(4): 388-388. doi: 10.11781/sysydz199704388
Abstract: