Muglad盆地Kaikang槽西斜坡沉积演化及其油气地质意义
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摘要
Muglad盆地Kaikang槽西斜坡为富油气区带,但一直未获得重大勘探发现。为研究其油气成藏条件和多期构造运动的控藏机理,开展了精细地震解释、沉积相分析和沉积演化研究。结果表明:①研究区经历了3期重要的构造运动,形成了2套主力含油气系统,分别为上部的Nayil组上段湖相泥岩盖层-Nayil组下段三角洲相砂岩储层组合和下部的Aradeiba组湖相泥岩盖层-Bentiu组河流相砂岩储层组合;②早白垩世第Ⅰ裂陷-坳陷期控制了斜坡区AG组烃源岩的展布范围,晚白垩世第Ⅱ裂陷-坳陷期控制了下部储盖组合的圈闭形成,古近纪第Ⅲ裂陷-坳陷期对应于研究区的主力生排烃期。上述3期构造运动造就了研究区"断层-盖层控藏、多层系差异聚集"的油气富集模式。
The west slope of Kaikang trough in Muglad Basin has been proven as a hydrocarbon-enriched belt.However,no significant exploration breakthrough has been gained. In order to study hydrocarbon accumulation conditions and reservoir-controlling mechanism of multi-stage tectonic movements,fine seismic interpretation,sedimentary facies analysis and sedimentary evolution were analyzed. The results show that:(1)The study area underwent three stages of tectonic movement and formed two sets of major petroleum systems,the upper play(lacustrine mudstone seal of upper Nayil Formation and delta sandstone reservoir of lower Nayil Formation)and the lower play(lacustrine mudstone seal of Aradeiba Formation and fluvial sandstone reservoir of Bentiu Formation);(2)The stage Ⅰ rifting-depression of Early Cretaceous controlled the distribution of in-place source rock of AG Formation in the slope area,stage Ⅱ rifting-depression of Late Cretaceous controlled the development of traps in the lower play,and stage Ⅲ rifting-depression of Paleogene controlled the major period of hydrocarbon generation and expulsion that matched with the rifting. The three stages of tectonic-sedimentary evolution worked together to gain the hydrocarbon enrichment model of"fault-seal control the accumulation together,differential accumulation in multi layers"in the west slope of Kaikang trough.
The west slope of Kaikang trough in Muglad Basin has been proven as a hydrocarbon-enriched belt.However,no significant exploration breakthrough has been gained. In order to study hydrocarbon accumulation conditions and reservoir-controlling mechanism of multi-stage tectonic movements,fine seismic interpretation,sedimentary facies analysis and sedimentary evolution were analyzed. The results show that:(1)The study area underwent three stages of tectonic movement and formed two sets of major petroleum systems,the upper play(lacustrine mudstone seal of upper Nayil Formation and delta sandstone reservoir of lower Nayil Formation)and the lower play(lacustrine mudstone seal of Aradeiba Formation and fluvial sandstone reservoir of Bentiu Formation);(2)The stage Ⅰ rifting-depression of Early Cretaceous controlled the distribution of in-place source rock of AG Formation in the slope area,stage Ⅱ rifting-depression of Late Cretaceous controlled the development of traps in the lower play,and stage Ⅲ rifting-depression of Paleogene controlled the major period of hydrocarbon generation and expulsion that matched with the rifting. The three stages of tectonic-sedimentary evolution worked together to gain the hydrocarbon enrichment model of"fault-seal control the accumulation together,differential accumulation in multi layers"in the west slope of Kaikang trough.
引文
[1]窦立荣.苏丹迈努特盆地油气成藏机理和成藏模式.矿物岩石地球化学通报,2005,24(1):50-57.DOU L R. Formation mechanism and model of oil and gas accumulations in the Melut Basin,Sudan. Bulletin of Mineralogy,Petrology and Geochemistry,2005,24(1):50-57.
[2] IBRAHIM A E,EBINGER C J,FAIRHEAD J D. Lithospheric extension northwest of the Central African Shear Zone in Sudan from potential field studies. Tectonophysics,1996,255(1):79-97.
[3] MOHAMED A Y,PEARSON M J,ASHCROFT W A,et al.Modeling petroleum generation in the southern Muglad rift Basin,Sudan. AAPG Bulletin,1999,83(12):1943-1964.
[4]张亚敏,陈发景.穆格莱德盆地形成特点与勘探潜力.石油与天然气地质,2002,23(3):236-240.ZHANG Y M,CHEN F J. The development feature and hydrocarbon exploration potential in Muglud Basin. Oil&Gas Geology,2002,23(3):236-240.
[5]童晓光,窦立荣,田作基,等.苏丹穆格莱特盆地的地质模式和成藏模式.石油学报,2004,25(1):19-24.TONG X G,DOU L R,TIAN Z J,et al. Geological mode and hydrocarbon accumulation mode in Muglad passive rift basin of Sudan. Acta Petrolei Sinica,2004,25(1):19-24.
[6]窦立荣,张志伟,程顶胜.苏丹Muglad盆地区域盖层对油藏特征的控制作用.石油学报,2006,27(3):22-26.DOU L R,ZHANG Z W,CHENG D S. Regional seal control on oil accumulation in Muglad Basin of Sudan. Acta Petrolei Sinica,2006,27(3):22-26.
[7]陈彬滔,史忠生,薛罗,等.古潜山周缘滩坝沉积模式与岩性油藏勘探实践:以南苏丹Melut盆地Ruman地区Galhak组为例.岩性油气藏,2018,30(6):37-44.CHEN B T,SHI Z S,XUE L,et al. Depositional models and lithologic reservoir exploration of sandy beach bar around buriedhill:a case from Galhak Formation in Ruman region of Melut Basin,South Sudan. Lithologic Reservoirs,2018,30(6):37-44.
[8]贾义蓉,方乐华,李碧宁,等.中非Muglad盆地1/2/4区块白垩系构造特征与油气分布.石油物探,2012,51(3):296-303.JIA Y R,FANG L H,LI B N,et al. Structural characteristics and hydrocarbon distribution of Cretaceous at 1/2/4 blocks in Muglad Basin,Central Africa. Geophysical Prospecting for Petroleum,2012,51(3):296-303.
[9]史忠生,方乐华,王天奇,等.苏丹—南苏丹Muglad盆地构造对油气成藏控制作用研究.地质论评,2014,60(2):389-396.SHI Z S,FANG L H,WANG T Q,et al. Controlling effect of basin structure on hydrocarbon accumulation in Muglad Basin,Sudan-South Sudan. Geological Review,2014,60(2):389-396.
[10]王秀林,汪望泉,李素珍,等. M盆地的构造特征及与油气的关系.石油与天然气地质,2000,21(1):76-79.WANG X L,WANG W Q,LI S Z,et al. Structural feature of M basin and its relation to oil and gas. Oil&Gas Geology,2000,21(1):76-79.
[11] MOHAMED A Y,PEARSON M J,ASHCROFT W A. Petroleum maturation modeling,Abu Gabra-Sharaf area,Muglad Basin,Sudan. Journal of African Earth Sciences,2002,35(2):331-344.
[12] MUSTAFA A A,TYSON R V. Organic facies of early Cretaceous synrift lacustrine source rocks from the Muglad Basin,Sudan.Journal of Petroleum Geology,2002,25(3):351-366.
[13] MCHARGUE T R,HEIDRICK T L,LIVINGSTON J K. Tectonostratigraphic development of the interior Sudan rifts,Central Africa. Tectonophysics,1992,213(1/2):187-202.
[14] MOHAMED A Y,ASHCROFT W A,WHITEMAN A J. Structural development and crustal stretching in the Muglad Basin,southern Sudan. Journal of African Earth Sciences,2001,32(2):179-191.
[15]冉怀江,范乐元,胡圣利,等.苏丹Muglad盆地凯康凹陷西斜坡早白垩世沉积层序及其控制因素研究.现代地质,2014,28(4):799-805.RAN H J,FAN L Y,HU S L,et al. Study of sedimentary sequence of the Early Cretaceous of the western trend of Kaikang Depression of Sudan and its controlling factors. Geoscience,2014,28(4):799-805.
[2] IBRAHIM A E,EBINGER C J,FAIRHEAD J D. Lithospheric extension northwest of the Central African Shear Zone in Sudan from potential field studies. Tectonophysics,1996,255(1):79-97.
[3] MOHAMED A Y,PEARSON M J,ASHCROFT W A,et al.Modeling petroleum generation in the southern Muglad rift Basin,Sudan. AAPG Bulletin,1999,83(12):1943-1964.
[4]张亚敏,陈发景.穆格莱德盆地形成特点与勘探潜力.石油与天然气地质,2002,23(3):236-240.ZHANG Y M,CHEN F J. The development feature and hydrocarbon exploration potential in Muglud Basin. Oil&Gas Geology,2002,23(3):236-240.
[5]童晓光,窦立荣,田作基,等.苏丹穆格莱特盆地的地质模式和成藏模式.石油学报,2004,25(1):19-24.TONG X G,DOU L R,TIAN Z J,et al. Geological mode and hydrocarbon accumulation mode in Muglad passive rift basin of Sudan. Acta Petrolei Sinica,2004,25(1):19-24.
[6]窦立荣,张志伟,程顶胜.苏丹Muglad盆地区域盖层对油藏特征的控制作用.石油学报,2006,27(3):22-26.DOU L R,ZHANG Z W,CHENG D S. Regional seal control on oil accumulation in Muglad Basin of Sudan. Acta Petrolei Sinica,2006,27(3):22-26.
[7]陈彬滔,史忠生,薛罗,等.古潜山周缘滩坝沉积模式与岩性油藏勘探实践:以南苏丹Melut盆地Ruman地区Galhak组为例.岩性油气藏,2018,30(6):37-44.CHEN B T,SHI Z S,XUE L,et al. Depositional models and lithologic reservoir exploration of sandy beach bar around buriedhill:a case from Galhak Formation in Ruman region of Melut Basin,South Sudan. Lithologic Reservoirs,2018,30(6):37-44.
[8]贾义蓉,方乐华,李碧宁,等.中非Muglad盆地1/2/4区块白垩系构造特征与油气分布.石油物探,2012,51(3):296-303.JIA Y R,FANG L H,LI B N,et al. Structural characteristics and hydrocarbon distribution of Cretaceous at 1/2/4 blocks in Muglad Basin,Central Africa. Geophysical Prospecting for Petroleum,2012,51(3):296-303.
[9]史忠生,方乐华,王天奇,等.苏丹—南苏丹Muglad盆地构造对油气成藏控制作用研究.地质论评,2014,60(2):389-396.SHI Z S,FANG L H,WANG T Q,et al. Controlling effect of basin structure on hydrocarbon accumulation in Muglad Basin,Sudan-South Sudan. Geological Review,2014,60(2):389-396.
[10]王秀林,汪望泉,李素珍,等. M盆地的构造特征及与油气的关系.石油与天然气地质,2000,21(1):76-79.WANG X L,WANG W Q,LI S Z,et al. Structural feature of M basin and its relation to oil and gas. Oil&Gas Geology,2000,21(1):76-79.
[11] MOHAMED A Y,PEARSON M J,ASHCROFT W A. Petroleum maturation modeling,Abu Gabra-Sharaf area,Muglad Basin,Sudan. Journal of African Earth Sciences,2002,35(2):331-344.
[12] MUSTAFA A A,TYSON R V. Organic facies of early Cretaceous synrift lacustrine source rocks from the Muglad Basin,Sudan.Journal of Petroleum Geology,2002,25(3):351-366.
[13] MCHARGUE T R,HEIDRICK T L,LIVINGSTON J K. Tectonostratigraphic development of the interior Sudan rifts,Central Africa. Tectonophysics,1992,213(1/2):187-202.
[14] MOHAMED A Y,ASHCROFT W A,WHITEMAN A J. Structural development and crustal stretching in the Muglad Basin,southern Sudan. Journal of African Earth Sciences,2001,32(2):179-191.
[15]冉怀江,范乐元,胡圣利,等.苏丹Muglad盆地凯康凹陷西斜坡早白垩世沉积层序及其控制因素研究.现代地质,2014,28(4):799-805.RAN H J,FAN L Y,HU S L,et al. Study of sedimentary sequence of the Early Cretaceous of the western trend of Kaikang Depression of Sudan and its controlling factors. Geoscience,2014,28(4):799-805.