2006 Vol. 28, No. 5

Display Method:
STRUCTURAL SIGNIFICANCE OF BRINK SAGS IN THE BOHAI BAY BASIN
Zhang Shulin, Fei Qi, Ye Jiaren
2006, 28(5): 409-413. doi: 10.11781/sysydz200605409
Abstract:
According to the structural characteristics of brink sags in the Bohai Bay Basin,the formation and evolvement of the basin show the characteristics of passive rift basins,which are provided with inheritance,multi-direction extension and rotation strike-slip.In co-ordination with the structural characteristics of host sags,the rift-subsidence which occurred in Cenozoic in the background of area stress actions and fault-block movements in the Bohai Bay Basin is summarized in this paper.Together with the northward extension caused by the unbalance of fault blocks moving northward,the northern plate extended north-westward inner due to the difference of movement between speed and distance from the east to the west of the plate.During the differential movement of fault-blocks tilting and extending process,the Tan-Lu fault belt adjusted in the strike-slip process and made shearing stress release effectively.At the same time,a series of strike-slip sags were formed along the fault belt.The formation model of the Bohai Bay Basin can be summed up as:the crust extension-the crust rift and extension as well as the sub-geosphere viscoelasticity rheid becoming thinner-the mantle uplift-the mantle plume invasion and melting-(the crust rise and erosion)-the thermal subsidence.
STRUCTURAL STYLE OF THE SOUTHERN NORTH CHINA BASIN
Liang Jiwei, Xie Dongning, He Mingxi, Wang Zhizhan
2006, 28(5): 414-417. doi: 10.11781/sysydz200605414
Abstract:
Through the study of typical geologic and seismic sections in the southern North China Basin,the structural styles are analyzed and classified.There are 5 main structural styles:thrust,extension,strike-slip,inversion and gravity decollement.Based on the structural style analysis,the basin property and regional tectonic background of the southern North China Basin are discussed.The relation between hydrocarbon accumulation and structural style of the southern North China Basin are also discussed.Exploration practices have indicated that,petroleum usually accumulates in extensional traps,and thrust and inversion traps also deserve attention.
THE FORMATION AND PETROLEUM-BEARING CAPACITY OF TRAPS IN THE FRONTAL UPLIFT OF THE FORELAND BASIN——TAKING THE SHAYA UPLIFT OF THE TARIM BASIN AS AN EXAMPLE
He Faqi, Mei Lianfu, Fei Qi, Xu Sihuang, Ma Lixiang
2006, 28(5): 418-423. doi: 10.11781/sysydz200605418
Abstract(1316) PDF-CN(348)
Abstract:
The frontal uplift of the foreland basin is an important petroleum accumulation zone.Its special tectonic location and complicated dynamic evolution process have led to the formation and distribution of traps.The Shaya Frontal Uplift in the petroleum system sourced from Triassic and Jurassic in the Kuqa Basin of the Tarim Basin has experienced 4 stages of tectonic movement:compression and rudiment formation(Hercynian),compression finalization(Indosinian-early Yanshanian),arch(late Yanshanian-middle Himalayan),compression and depression(late Himalayan).Relation exists between trap formations and tectonic movements,accumulations and source rock evolutions as well as episodic tectonic movements;hence the petroleum-bearing capacity of traps is closely related to trap formation and petroleum migration stages.3 levels of favorable tectonic zones are divided in the Shaya Frontal Uplift.
DISCUSS ON MEANING AND MOSTLY TYPE OF COMPARTMENT
Zhou Xingxi
2006, 28(5): 424-429. doi: 10.11781/sysydz200605424
Abstract:
Compartment is an important and universal structure in sediment basin,and its basic character is provided with barriers or seals for liquid and energy in three dimensions space.It has relative separability,and its liquid and energy could exchange with environment under relevant condition.It always is important geology entity forming and preserving of giant and middle sized oil-gas field.Not only overpressure and underpressure but also normalpressure compartment exist in nature,but the later often was overlooked.The giant and middle sized oil-gas field distributes mostly inside compartment containing hydrocarbon kitchen or near top and side seal of this kind of compartment.Study of compartment regard as one key of exploration decision-making process and the probability of discovery of giant and middle sized oil-gas field.
FORMING MECHANISM OF SLOPE-BREAK AND ITS CONTROL ON SYN-DEPOSITIONAL FAULT AND DEPOSITION IN HALFGRABEN SAG—A CASE STUDY OF THE NANGYANG SAG, THE NANXIANG BASIN
Fu Zhifang, Tang Dazhen, Xu Hao, Yang Fang
2006, 28(5): 430-433. doi: 10.11781/sysydz200605430
Abstract:
The slope-break zone is a pivotal zone of depositional physiognomy.The listric normal faults in the south of Nanyang Sag glide on lumpy surface and result in the gentle wrenches of cap formation in the north,serving as the boundary between depositional regions.Syn-depositional faults and sedimentary facies changes mainly take place here.Certain slope-break zone types indicate the activities and distributions of syn-depositional faults and control sediment dispersal and sand body accumulation.During different stages of basin evolution,syn-depositional faults and sedimentary facies belts control the gene-ration of different traps.
FAULT SEALING IN YAKELA-LUNTAI AREA, THE TARIM BASIN
Wang Bin, Yuan Yueqin, Zhou Jiangyu, Jie Yixin
2006, 28(5): 434-439. doi: 10.11781/sysydz200605434
Abstract:
Most traps and pools in Yakela-Luntai area of the Tarim Basin are closely related to faults,which play a very important role in trap formation and hydrocarbon accumulation.Therefore,integrated research of fault sealing has become a decisive factor of the exploration in the area.The fault sealing of four typical fault-screened reservoirs in this area has been studied by geological qualitative analysis,(Allen)cross-section analysis,shale smear factor,etc.,so as to establish a standard evaluation criteria of fault sealing which can be used in the general appraisal of Yakela-Luntai area.In conclusion,faults seal well in the whole area,and control trap formation and hydrocarbon accumulation.Series of pools have been discovered along the fault belts.The Ya'nan Fault seals better in the east and the underlayer than in the west and the upside.Obviously,the Luntai Fault seals variously in different part and depth,in brief better in the east part(near Yegen area)than the west.
RESERVOIR CHARACTERISTICS AND ENRICHMENT MECHANISM OF THE COAL-BED GAS IN THE NORTH OF QINSHUI BASIN
Wang Mingshou, Tang Dazhen, Wei Yongpei, Xu Wenjun, Leng Xue
2006, 28(5): 440-444. doi: 10.11781/sysydz200605440
Abstract:
Coalbed methane(CBM)enrichment depends on the reservoir's characteristics,and it is also controlled by geologic setting.On the basis of detailed study on the reservoir's characteristics and CBM enrichment mechanism,the favorable exploitation prospect in the north of Qinshui Basin is demonstrated.The observation and test for the type,quality and structure of coal as well as the porosity,permeability and adsorbability show that the coal bed in this area is characterized by thick reservoir,high thermal evolution,local structural coal,devoloped fracture,high adsorbability,high gas content and low gas saturation.In one word,the research area fits for CBM exploitation.The CBM enrichment in the research area is controlled by thermal evolution history and burial history.Owing to magma thermal metamorphism superimposing on the regional metamorphosis,the intensity of gas generation is higher.Moreover,the burial depth,closure property of adjacent rock and hydrologic geology condition also(affect)gas content.The CBM enrichment is the result of effective multifactorial macthing.
THE PETROLEUM SYSTEM AND EXPLORATION PROSPECT IN THE EAST OF NORTH YELLOW SEA BASIN
Kim in Sik, Fei Qi, Yang Xianghua, Cai Feng
2006, 28(5): 445-449. doi: 10.11781/sysydz200605445
Abstract:
The North Yellow Sea Basin(called West Korean Bay Basin in the eastern Korean region)is one of the sedimentary basins distributing along the Qingchuanjiang fault zone where there are thick Meso-Cenozoic sedimentary rocks.There are a series of Meso-Cenozoic sedimentary basins,such as Anzhou Basin,Bohai Bay Basin,Laiyang Basin and South Yellow Sea Basin in the vicinity of the North Yellow Sea Basin.The basins mentioned above belong to Meso-Cenozoic superimposed basinS which display great petroleum prospects.Huge faults,such as Tanlu Fault,Qingchuanjiang Fault and Linjinjiang Fault,have close relationship with petroleum migration and accumulation in the North Yellow Sea Basin.Based on the integrated researches on reservoir,oil generation and trap types,the petroleum prospects of North Yellow Sea Basin is determined.
OIL SOURCE AND HYDROCARBON MIGRATION PROCESS IN QIANGTANG BASIN,QINGHAI-TIBET PLATEAU
Qin Jianzhong
2006, 28(5): 450-457. doi: 10.11781/sysydz200605450
Abstract:
The oil seepages from the formations of J2b in West Longeni,J3s in Angdaercuo,J3s in West Changliang and J3s in the area of No.114 Anduo road maintenance squad as well as the J2x hydrocarbon-rich shale in Biluocuo and the J3s dark-gray limestone in the area of No.114 road maintenance squad are characterized by high rearrangement sterane content,low pregnane,triclene and gammacerane contents,high ratio of Pr/Ph as well as heavy carbon-isotope.The oil seepages in the formations of J2b in West Longeni and J3s in Angdaercuo originate from the J2x lagoon-phase hydrocarbon-rich source rock in their corresponding areas.The oil seepages in the formations of J3s in the areas of No.114 Anduo road maintenance squad and West Changliang originate from the J3s platform facies dark-gray limestone and hydrocarbon-rich shale.There are "light active oil" and "solid bitumen" in the oil-bearing dolomite in center of the basin and in the J3s lime-rubble rock in No.114 Anduo road maintenance squad area.The solid bitumen is product of the first hydrocarbon migration and accumulation.The fluorescent light active oil is product of the second or third hydrocarbon migration and accumulation causing by reburial or tectogenesis.They have undergone two or more hydrocarbon generation and migration processes.
VARIETY REGULARITY OF OIL AS WELL AS FORMATION WATER PROPERTY AND HYDROCARBON GATHERING IN THE DAMINTUN SAG OF THE LIAOHE BASIN
Guo Jianhua, Wu Dongsheng, Liu Chensheng
2006, 28(5): 458-462. doi: 10.11781/sysydz200605458
Abstract:
According to analysis of formation water and crude oil at the west Jinganpu of Damintun Sag in the Liaohe Basin,type NaHCO3 formation water on the top of the burial hills in the studied area is dominative,type CaCl2 appear in local area.The result reflects that environment on the top of the burial hills is open and water can alternate in this environment,but it is closed in local area.This enclosed environment is the result of close faults and overlying undercompacting mudstone.Mineralization degree of formation water has the trend that value increase from west to east and the lowest value in west is only(1500mg/L),but in east the value is amount to 9 378.69 mg/L.The zone that presents high degree of mineralization is favorable area that gathers hydrocarbon.Physical property and geochemistry feature of crude oil indicate that migration length of hydrocarbon is short.But in this short distance,the crude property takes place great change.The changes of geochemistry feature show the hydrocarbon migration direction and gathering location.
RESEARCH TO THE NATURAL GAS INCLUSIONS CONTAINED IN CALCITE VEIN FILLED IN A BIG FAULT BELT ACROSS THE MIDDLE OF ORDOS BASIN
Li Rongxi, Xi Shengli, Di Lingjun
2006, 28(5): 463-466. doi: 10.11781/sysydz200605463
Abstract:
Himalayan tectonic movement has significant influence on the geology evolution and the oil-gas reservoir formation in the Ordos Basin.Large numbers of natural gas inclusions were found in the calcite vein filled in the structure joint and the fractures in the area of Triassic outcrop near the south margin of Mizi big natural gas field in the Eastern Ordos Basin.Analysis results shown that the organic inclusions formed at the temperature of 130~140℃ with H2S of 21.1% and total gaseous hydrocarbon of 78.9% including C4 of 51.8%.The organic matter of the natural gas inclusions is mainly saturated hydrocarbon of C19-C27 with the even carbon dominance.It is proposed that natural gas of the inclusions came from the carbonate source rock,which is also the main source rock of the Mizi big natural gas field.It is indicated that the natural gas inclusion was the marker of the natural gas migration from the Paleozoic gas reservoir through the structure joint and the fracture due to the Himalayan tectonic movement.
STUDY OF THE PHYSICAL AND CHEMICAL CHARACTERISTICS OF THE CRUDE OIL AND OIL-SOURCE CORRELATION IN THE YANQI BASIN
Yan Yongxin, Yuan Guangxi, Ma Rongfang, Gu Zhe, Bai Yunfei
2006, 28(5): 467-471. doi: 10.11781/sysydz200605467
Abstract:
At present,there are different opinions on the oil sources of the Jurassic net pay in Yanqi Basin,where crude oil has been found in Sangonghe Formation and Badaowan Formation.Through a series of researches on the physical and chemical characteristics of the crude oil in the study area,some differences between the oils in the two Formations have been found not only on the physical properties but also on the geochemical composition and biomarkers.Therefore,the crude oils in the area are considered to have different oil sources.The crude oil in Sangonghe Formation is attributed to typical humic kerogen origin.Besides having the same characteristics with the crude oil in Sangonghe Formation,the crude oil in Badaowan Formation comes from lacustrine mudstone.The further correlation analysis on the crude oil and various biomarkers shows that the crude oil in the Jurassic Sangonghe Formation differs greatly from the source rocks in Xishanyao Formation,Sangonghe Formation,Carboniferous and Triassic on geochemical characteristics,but is correlative with the source rock in Badaowan Formation.It is concluded that the curde oil in Badaowan Formation has good similarity with the source rock in Badao-wan Formation and the Triassic.Up to now,the exploration has been focused on the source rock in(Badaowan)Formation which is believed to be the main source rock.The favorable zones in the Triassic,which is thought to be a secondary source rock,should be paid more attention in next exploration deployment.
FORMATION AND IDENTIFICATION OF THE OIL WATER INTERVALS IN FUYU-YANGDACHENGZI PAY ZONE IN THE WEST OF DAQING PLACANTICLINE
Zhao Wenge, Huang Wei, Lin Jingye, Zhang Fan
2006, 28(5): 472-475. doi: 10.11781/sysydz200605472
Abstract:
Starting from the formation principle of the special reservoir with top generation-bottom accumulation and combining the exploration practices for Fuyu-Yangdachengzi pay zone in the west of Daqing placanticline in the Songliao Basin,the formation mechanism of the water/oil intervals in Fuyu-Yangdachengzi pay zone was discussed in detail.Research shows that the water/oil intervals in Fuyu-Yangdachengzi pay zone formed under the reservoir-forming condition of taking the overpressure of overlying source rock as driving force.Oil mixing with water migrate into the reservoir.Because the pore throat of reservoir is small,gravitational differentiation of oil and water is not good leading to the oil in pore and water in throat.For this low permeation reservoir,the pore configuration is complicated,the oil saturation is low and the distribution of oil and water in pore is special.These make the electrical resistance curve reflecting fluid information and the identification of water/oil intervals more difficult.For this reason,the method of distinguishing water/oil/gas intervals by multiple parameter decrease dimensionality is put forword and achieved a good effect in actual application.
ACCUMULATION HISTORY OF THE DAERQI OIL POOL IN THE BAIYINCHAGAN SAG, THE ERLIAN BASIN
Sun Yipu, Lin Renzi
2006, 28(5): 476-479. doi: 10.11781/sysydz200605476
Abstract:
The Daerqi structure is a very important oil-bearing structure in the Baiyinchagan Sag,the Erlian Basin.Based on seismic lines,hydrocarbon source rock,lithology,thermal stream and test data,a two dimensional forward model of the basin has been made.Histories of filling,thermal stream,maturity,hydrocarbon generation,discharge and migration are analyzed.Oil mainly deposits in the Tenggeer Formation and the lowest part of the Duhongmu Formation in the Daerqi structure.In the western nose of the Daerqi structure,oil in the lowest part of the Duhongmu Formation mostly locates below the Baiyin fault and oil in the Tenggeer Formation mostly locates upon the Baiyin fault.In the eastern nose of the Daerqi structure,oil mostly deposits in the lowest part of the Duhongmu Formation and oil in the Tenggeer Formation mostly locates in the higher structure.Accumulation evolution of the Daerqi structure can be divided into four periods:the first accumulation period,the second accumulation period,the scattering period and the stable period.The first accumulation period is the main accumulation period.Oil scatters in the lower position.Accumulation history of the Tenggeer Formation is more complicated than that of the lowest part of the Duhongmu Formation.The southern slope is the main target of petroleum migration and should be focused on.
GEOCHEMICAL CHARACTERISTIC OF CHANGDEDONG CO2 GAS RESERVOIR IN THE NORTHERN SONGLIAO BASIN
Tan Ying, Liu Deliang, Li Zhensheng
2006, 28(5): 480-483. doi: 10.11781/sysydz200605480
Abstract:
Industrial CO2 gas reservoirs discovered in the northern Songliao Basin locate mostly in the deep strata of the Xujiaweizi Fault Depression.The identification of origin of CO2 in the reservoirs would be significant to research the model to form deep gas reservoirs.It was suggested that the volcanic rocks in deep strata of this area were calc-alkaline and differential production of mantle-derived magma by petrochemical data of reservoir rocks.In the Changdedong gas reservoir of Xujiaweizi area,the CO2 contents are 89.73%~90.38% and δ13CCO2 are -6.61‰~-4.06‰,which suggested that CO2 is inorganic origin;3He/4He ratios are 3.9×10-6 and 4.5×10-6,which is between mantle-derived and crust derived origin.There is reverse order of carbon isotopic ratio to accompanying methane homologous compounds,which is characteristic of inorganic origin.The CO2/3He ratio of 1.9×109 indicated that CO2 in this reservoir should be from degassing of upper mantle.The formation of the Changdedong gas reservoir was related to mantle-derived magma,and the CO2 gas was inorganic and mantle-derived.
THE PETROLEUM GEOLOGICAL SIGNIFICANCE OF PHSICALLY-ABSOBED GAS
Li Guangzhi, Cheng Tongjin, Tang Yuping, Deng Tianlong
2006, 28(5): 484-488. doi: 10.11781/sysydz200605484
Abstract:
In the process of the light hydrocarbons in oil or gas reservoirs exchanging substance and energy with surrounding material,all states of light hydrocarbons form a dynamical equilibrium under the action of the surface of sediment.According to the composition and content of physically-absorbed light hydrocarbons,we can trace the source of light hydrocarbons(i.e.oil or gas reservoirs),and further predict or deduce the properties and characteristics of oil or gas reservoirs.By the technology of physically-absorbed light hydrocarbons,the physically-absorbed gas is completely released from the sample in a vacuum state.The light hydrocarbon compositions are analyzed qualitatively and quantitatively with gas-chromatogram.The properties and characteristics of oil or gas reservoirs are determined according to the variety of light hydrocarbon concentration.The technology of physically-absorbed light hydrocarbons got very good application results in Xinchang gas field in Sichuan Basin,Zhenyuan-Jingchuan loes-sial plateau in Ordos Basin and Chaiwopu gobi area in Tarim Basin.This technology has a very good prospect in application and popularization.
MICRO-ANALYSIS AND ITS APPLICATION OF OIL AND GAS RESERVOIR CHARACTERISTICS
Liu Weixin, Cheng Qiuquan, Wang Yanbin, Guo Li Qin, Jianzhong
2006, 28(5): 489-492. doi: 10.11781/sysydz200605489
Abstract:
The micro-analysis of mineral genesis,deposition environment and diagenesis process of oil and gas reservoir has played an important role in the quality evaluation of carbonate and clastic rock reservoirs.It is used in the research of clay mineral swelling and evolution in hydrocarbon zone protection and field exploration.The ESEM deals with samples bearing oil or water,hence reveals the changes of mineral rock more precisely.From the aspects of reservoir diagenesis,clay mineral characteristics and micro-pore generation,it is discussed in this paper the application of SEM/ESEM/EDX as modern testing technology in petroleum exploration and production.
INFLUENCE OF CLAY MINERALS MEMBRANE ON SANDSTONE RESERVOIRS——A CASE STUDY ON THE LOWER DONGHETANG RESERVOIRS OF THE DEVONIAN OF WELL QUN 6 IN THE TARIM BASIN
Zhang Huiliang, Zhang Ronghu, Wang Yuehua, Zhu Guohua, Li Yuwen
2006, 28(5): 493-498. doi: 10.11781/sysydz200605493
Abstract:
According to cast liquid photo,scan electron microscope,impressing hydrargyrum,quality etc.,the research thinks that clay minerals membrane of the lower Donghetang reservoir of the Devonian in well qun 6 area of the Tarim Basin is divided into original cause and self-generating cause,among them with self-generating cause for most.Clay minerals membrane usually comes into being in earlier diagenetic stage(or developing together diagenetic stage),which have a just relation to the face porosity of the reservoir,and a negative relation to the pore structure.Porosity of the lower Donghetang reservoir developing clay minerals membrane is most of 7%~17.6%(mean of 11.53%)and permeability is most of(0.1~10)×10-3μm2(mean of 4.15×10-3μm2),and these quality is obviously higher than the upper Donghetang reservoir not developing clay minerals membrane,whose mean porosity is 5.23% and mean permeability is 2.88×10-3μm2.Clay minerals membrane has a close relation to depositional facies,temperature and pressure system of reservoir,earlier hydrocarbon infusion.Generally speaking,clay minerals membrane develops in lower-middle shore face more familiar,while is short in the upper shore face and foreshore where clay is washed cleanlily.Hydrocarbon infusion in earlier diagenetic stage and abnormal high pressure system(well qun 6 area pressure coefficients for 1.59)have crucial function to protect clay minerals membrane.
PETROLEUM GEOLOGIC CHARACTERISTICS AND EXPLORATION PROSPECT OF THE DELINGHA FAULT-DEPRESSION IN THE QAIDAM BASIN
Gan Guiyuan, Yan Xiaolan, Zhao Dongsheng, Xiong Deming
2006, 28(5): 499-503. doi: 10.11781/sysydz200605499
Abstract:
The Delingha Fault-depression in the north margin of the Qaidam Basin is a frontier of petroleum exploration.Combining the field petroleum geologic review on the outcrops with the well and seismic information,the mudstone,carbonate rock and coal-measure hydrocarbon source rocks in the Mesozoic Jurassic and Paleozoic Carboniferous are considered widely developing in the Delingha Fault-Depression.The mudstone and carbonate rock in the Ordovician are also good hydrocarbon source rocks.The sandstone reservoirs developed in both the Mesozoic and the Cenozoic.The Delingha Fault-Depression is of two segs mingle with one uplift in structural framework.In the Delingha Fault-Depression,the tectonics developed and the traps are characterized by various types,large quantities and area as well as burial depth less than 4 000 meters.These are favorable for drilling.The total forecasting oil/gas reserve in this area is above 10 million tons.It is a favorable area for oil and gas exploration,and has well exploration prospect.
CHARACTERISTICS OF DAWSONITE AND IT’S PETROLEUM GEOLOGIC SIGNIFICANCE IN THE HAILAER BASIN
Sun Y, a
2006, 28(5): 504-506. doi: 10.11781/sysydz200605504
Abstract:
The dawsonite in oil-bearing reservoir was identified accurately with X-ray diffraction method for the first time in China,and its diffraction characteristics was given in detail.Research shows that the dawsonite in Hailaer Basin exists in both the eroded volcano tuff and sedimentary volcano tuff,and is paragenous with corrensite and allevardite frequently.This paragenetic association is one of the typomorphic minerals of eroded volcano tuff and sedimentary volcano tuff.The dawsonite in the Hailaer Basin forms by typical alkaline metasomatosis,because the volcano tuff is easily eroded under the alkaline conditions.The plagioclase alkaline metasomatosis by dawsonite results in the formation of the secondary porosity contributing to the hydrocarbon accumulation,which constitutes dominating oil-bearing reserver in some regions.