乍得Bongor盆地储层沉积成岩特征及其主控因素
|
摘要
乍得Bongor盆地储层沉积成岩特征具有明显的独特性。结合盆地区域构造演化,利用地震、钻井、岩心、薄片、测试等资料,系统分析了Bongor盆地主力储层沉积展布特征和成岩演化。研究结果表明:Bongor盆地早白垩世强烈拉张裂陷作用形成了一系列NW-SE向深陡凹陷,主力储层局限分布在凹陷内部,以近岸水下扇沉积为主,毗邻控凹断层分布,具有近源、深水、快速沉积特征,结构成熟度和成分成熟度均较低;受多期构造运动及烃类流体改造,储层压实作用不充分,胶结成岩作用减弱,溶蚀现象普遍,目前尚处于中成岩A期阶段;以原生孔隙为主,属中孔、中高渗储层,有效储层埋深下限明显大于现今油层深度,表明盆地深层仍发育有优质储层,具有良好的勘探潜力。
The sedimentary and diagenetic characteristics of reservoir were special in Bongor basin,Chad.Based on regional tectonic evolution and various basic data such as cores,thin sections,mud logging,test data and so on,the authors do systematic research on the sedimentary-diagenetic characteristics of reservoir sandstone.The results show that series of NW-SE depressions were formed during the early Cretaceous rifting stage by the NE-SW extension,which controlled the sediment source,the sandstone distribution patterns and formed lots of fans.These fans should be classified as subaqueous fans and mainly distributed along the boundary faults.The structure inversion of the Late Cretaceous induced large amount of erosion and uplifted the reservoir greatly.It also influenced the normal diagenesis process of the reservoir.Due to the tectonic evolution,the hydrocarbon infilling and compositional maturities,their mechanical compaction and cementation were relatively weak but the dissolution was relatively common.The diagenesis of reservoir sandstone was still under the substage of the middle diagenetic stage and has the good quality: medium porosity,medium-high permeability.The quantitative evaluation of the relationship between porosity and burial depth revealed that the depth limit of the effective reservoirs is much deeper than that of the present oil pay zones and the deep reservoir still has a good prospect of exploration.
The sedimentary and diagenetic characteristics of reservoir were special in Bongor basin,Chad.Based on regional tectonic evolution and various basic data such as cores,thin sections,mud logging,test data and so on,the authors do systematic research on the sedimentary-diagenetic characteristics of reservoir sandstone.The results show that series of NW-SE depressions were formed during the early Cretaceous rifting stage by the NE-SW extension,which controlled the sediment source,the sandstone distribution patterns and formed lots of fans.These fans should be classified as subaqueous fans and mainly distributed along the boundary faults.The structure inversion of the Late Cretaceous induced large amount of erosion and uplifted the reservoir greatly.It also influenced the normal diagenesis process of the reservoir.Due to the tectonic evolution,the hydrocarbon infilling and compositional maturities,their mechanical compaction and cementation were relatively weak but the dissolution was relatively common.The diagenesis of reservoir sandstone was still under the substage of the middle diagenetic stage and has the good quality: medium porosity,medium-high permeability.The quantitative evaluation of the relationship between porosity and burial depth revealed that the depth limit of the effective reservoirs is much deeper than that of the present oil pay zones and the deep reservoir still has a good prospect of exploration.
引文
[1]Guiraud R,Maurin J.Early Cretaceous Rifts of Westand Central Africa:An Overview[J].Tectonophysics,1992,213(1/2):153-168.
[2]Genik G J.Regional Framework,Structural and Pe-troleum Aspects of Rifts Basins in Niger,Chad andthe Central African Republic[J].Tectonophysics,1992,213(1/2):169-185.
[3]Genik G J.Petroleum Geology of Cretaceous-TertairyRift Basins in Niger,Chad and the Central African Re-public[J].AAPG Bulletin,1993,77(8):1405-1434.
[4]Faure H.Reconnaissance Geologiques Des FormationsSedimentaires Post Paleozoiques du Niger oriental[J].Memoires du Bureau de Recherche Geologique etMiniere,1966,47:629.
[5]Fairhead J D.Geophysical Controls on SedimentationWithin the African Rift Systems[C]//Frostick L E,Renault R W,Reid L,et al.Sedimentation in the Afri-can Rifts.[S.l.]:Geological Society of London,1986:19-27.
[6]Fairhead J D.Mesozoic Plate Reconstructions of theCentral South Atlantic Ocena:The Role of the Westand Central African Rift System[J].Tectonophysics,1988,15:181-191.
[7]Fairhead J D.Late Mesozoic Rifting in Africa[C]//Manspeizer W.Triassic-Jurassic Rifting,ContinentalBreakup and the Origin of the Atlantic Ocean and Pas-sive Margins.New York:Elsevier,1988:998.
[8]Scotese R S,Gahagan L M,Larson R L.Plate Tec-tonic Reconstructions of Cretaceous and Cenozoic O-cean Basins[J].American Journal of Science,1988,283:684-721.
[9]Schull T J.Rift Basins of Interior Sudan,PetroleumExploration and Discovery[J].AAPG Bulletin,1988,72:1128-1142.
[10]Daly J C,Chorowiez J,Fairhead J D.Rift BasinEvoluation in Africa:The Influence of ReactivedSteep Basement Shear Zones[C]//Cooper M A,Wil-liams G D.Inversin Tectonics.[S.l.]:GeologicalSociety,1989:308-334.
[11]欧阳文生,张红胜,王彤,等,苏丹Muglad盆地大型油气藏储集特征[J].资源与产业,2006,8(2):67-70.Ouyang Wensheng,Zhang Hongsheng,Wang Tong,et al.The Characteristics of Large Scale Oil Reservoirof Muglad Basin in Sudan[J].Researches and Indus-tries,2006,8(2):67-70.
[12]Wycisk P,Klitzsch E,Jas C,et al.Intracratonal Se-quence Development and Structural Control of Phan-erozoic Strata in Sudan[C]//Klitzsch E,Schrank E.Research in Sudan,Somalia,Egypt and Kenya.[S.l.]:Berliner Geowissen-Schaftliche Abhandlungen,1990:45-86.
[13]Fitton J G.The Benue Trough and Cameroon Line:AMigrating Rift System in West Africa[J].Earth andPlanetary Science Letters,1980,51:132-138.
[14]Guiraud R,Bellion J,Benkheil J.Post Hercynian Tec-tonics in Northern and Western Africa[J].GeologicalJournal,1987,22:433-466.
[15]Ziegler P A.Geological Atlas of Western and CentralEurope[M].2nd ed.London:Geological Society ofLondon,1992.
[16]Lowell J D,Genik G J.Sea Floor Spreading and St-ru-ctural Evolution of Southern Red Sea[J].AAPGBulletin,1972,56:247-259.
[17]Makris J,Rihm R.Shear Controlled Evolution of theRed Sea:Pull Apart Model[J].Tectonophysics,1991,(2/3/4):441-468.
[18]窦立荣,肖坤叶,胡勇,等.乍得Bongor盆地石油地质特征及成藏模式[J].石油学报,2011,32(3):379-386.Dou Lirong,Xiao Kunye,Hu Yong,et al.Petrole-um Geology and a Model of Hydrocarbon Accumula-tions in the Bongor Basin,the Republic of Chad[J].Acta Petrolei Sinica,2011,32(3):379-386.
[19]于波,崔智林,刘学刚,等.西峰油田长8储层砂岩成岩作用及对孔隙影响[J].吉林大学学报:地球科学版,2008,38(3):405-410,416.Yu Bo,Cui Zhilin,Liu Xuegang,et al.The Diagene-sis of Chang-8Reservoir Sandstone and Its Effect onPorosity in Xifeng Oilfield[J].Journal of Jilin Univer-sity:Earth Science Edition,2008,38(3):405-410,416.
[20]陈忠民,刘洛夫,卞德智,等.乍得南部B盆地下白垩统碎屑岩储集层成岩演化及特征[J].石油勘探与开发,2006,33(2):250-254.Chen Zhongmin,Liu Luofu,Bian Dezhi,et al.Dia-gentic Evolution and Characteristics of Lower Creta-ceous Clastic Reservoir of B Basin,South Chad[J].Petroleum Exploration and Development,2006,33(2):250-254.
[21]Athy L F.Density,Porosity and Compaction of Sedi-mentary Rocks[J].AAPG Bulletin,1930,14(1):1-24.
[2]Genik G J.Regional Framework,Structural and Pe-troleum Aspects of Rifts Basins in Niger,Chad andthe Central African Republic[J].Tectonophysics,1992,213(1/2):169-185.
[3]Genik G J.Petroleum Geology of Cretaceous-TertairyRift Basins in Niger,Chad and the Central African Re-public[J].AAPG Bulletin,1993,77(8):1405-1434.
[4]Faure H.Reconnaissance Geologiques Des FormationsSedimentaires Post Paleozoiques du Niger oriental[J].Memoires du Bureau de Recherche Geologique etMiniere,1966,47:629.
[5]Fairhead J D.Geophysical Controls on SedimentationWithin the African Rift Systems[C]//Frostick L E,Renault R W,Reid L,et al.Sedimentation in the Afri-can Rifts.[S.l.]:Geological Society of London,1986:19-27.
[6]Fairhead J D.Mesozoic Plate Reconstructions of theCentral South Atlantic Ocena:The Role of the Westand Central African Rift System[J].Tectonophysics,1988,15:181-191.
[7]Fairhead J D.Late Mesozoic Rifting in Africa[C]//Manspeizer W.Triassic-Jurassic Rifting,ContinentalBreakup and the Origin of the Atlantic Ocean and Pas-sive Margins.New York:Elsevier,1988:998.
[8]Scotese R S,Gahagan L M,Larson R L.Plate Tec-tonic Reconstructions of Cretaceous and Cenozoic O-cean Basins[J].American Journal of Science,1988,283:684-721.
[9]Schull T J.Rift Basins of Interior Sudan,PetroleumExploration and Discovery[J].AAPG Bulletin,1988,72:1128-1142.
[10]Daly J C,Chorowiez J,Fairhead J D.Rift BasinEvoluation in Africa:The Influence of ReactivedSteep Basement Shear Zones[C]//Cooper M A,Wil-liams G D.Inversin Tectonics.[S.l.]:GeologicalSociety,1989:308-334.
[11]欧阳文生,张红胜,王彤,等,苏丹Muglad盆地大型油气藏储集特征[J].资源与产业,2006,8(2):67-70.Ouyang Wensheng,Zhang Hongsheng,Wang Tong,et al.The Characteristics of Large Scale Oil Reservoirof Muglad Basin in Sudan[J].Researches and Indus-tries,2006,8(2):67-70.
[12]Wycisk P,Klitzsch E,Jas C,et al.Intracratonal Se-quence Development and Structural Control of Phan-erozoic Strata in Sudan[C]//Klitzsch E,Schrank E.Research in Sudan,Somalia,Egypt and Kenya.[S.l.]:Berliner Geowissen-Schaftliche Abhandlungen,1990:45-86.
[13]Fitton J G.The Benue Trough and Cameroon Line:AMigrating Rift System in West Africa[J].Earth andPlanetary Science Letters,1980,51:132-138.
[14]Guiraud R,Bellion J,Benkheil J.Post Hercynian Tec-tonics in Northern and Western Africa[J].GeologicalJournal,1987,22:433-466.
[15]Ziegler P A.Geological Atlas of Western and CentralEurope[M].2nd ed.London:Geological Society ofLondon,1992.
[16]Lowell J D,Genik G J.Sea Floor Spreading and St-ru-ctural Evolution of Southern Red Sea[J].AAPGBulletin,1972,56:247-259.
[17]Makris J,Rihm R.Shear Controlled Evolution of theRed Sea:Pull Apart Model[J].Tectonophysics,1991,(2/3/4):441-468.
[18]窦立荣,肖坤叶,胡勇,等.乍得Bongor盆地石油地质特征及成藏模式[J].石油学报,2011,32(3):379-386.Dou Lirong,Xiao Kunye,Hu Yong,et al.Petrole-um Geology and a Model of Hydrocarbon Accumula-tions in the Bongor Basin,the Republic of Chad[J].Acta Petrolei Sinica,2011,32(3):379-386.
[19]于波,崔智林,刘学刚,等.西峰油田长8储层砂岩成岩作用及对孔隙影响[J].吉林大学学报:地球科学版,2008,38(3):405-410,416.Yu Bo,Cui Zhilin,Liu Xuegang,et al.The Diagene-sis of Chang-8Reservoir Sandstone and Its Effect onPorosity in Xifeng Oilfield[J].Journal of Jilin Univer-sity:Earth Science Edition,2008,38(3):405-410,416.
[20]陈忠民,刘洛夫,卞德智,等.乍得南部B盆地下白垩统碎屑岩储集层成岩演化及特征[J].石油勘探与开发,2006,33(2):250-254.Chen Zhongmin,Liu Luofu,Bian Dezhi,et al.Dia-gentic Evolution and Characteristics of Lower Creta-ceous Clastic Reservoir of B Basin,South Chad[J].Petroleum Exploration and Development,2006,33(2):250-254.
[21]Athy L F.Density,Porosity and Compaction of Sedi-mentary Rocks[J].AAPG Bulletin,1930,14(1):1-24.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心