塔里木盆地库车坳陷东秋里塔格构造样式及勘探前景
|
摘要
库车坳陷是塔里木盆地油气勘探的三大阵地之一,近年来在大北—克深区带白垩系巴什基奇克组持续取得重大突破,已形成万亿方大气区。但位于库车坳陷中部的秋里塔格构造带一直未能获得重要进展,特别是秋里塔格东段先后3口探井均未能在白垩系获得工业油气流。前人主要认为该区构造类型是以基底卷入形成的大型背斜圈闭为主,目前实践证明这一认识制约了该区勘探发展。由此可见,取得油气地质新认识是获得突破的首要前提条件。基于地震资料重新处理的基础上,以前陆盆地系统体系为理论划分基础,开展对东秋里塔格构造样式的精细分析。通过地震精细解释、盐岩三角带分析、地表地质分析、平衡剖面分析和已钻井分析5个方面研究,表明该区与大北—克深构造样式相似,均发育塑性滑脱叠瓦冲断构造。并落实了东秋里塔格断裂下盘冲断圈闭具体形态和位置。进一步综合分析后该区油气地质条件优越:油源充足,紧临生烃中心,处于构造高部位,一直是油气运移的指向区;主要目的层巴什基奇克组发育与大北—克深相同的辫状河三角洲前缘砂体;并具有古近系和新近系2套膏盐岩区域盖层。由此得出东秋里塔格是目前库车坳陷新区中最有利、最现实的勘探区带。
Kuqa Depression is very important among the three oil and gas exploration zones in Tarim Basin.Continual important breakthroughs have been obtained in recent years,it has become a large oil and gas zone of 1×10~(12) m~3.But Qiulitage structural belt which lies in middle Kuqa Depression has still not significant stride,especially there is no commercial oil and gas flow in Cretaceous after three wells were drilled in the east Qiulitage.The main opinion of predecessors is that there are large anticlinal trap resulted from basement decollement,but now it is proved confinement for exploration.As a result,acquiring new geological viewpoint is a principal precondition for breakthroughs.Based on reprocess of seismic data,according to the theory of classification of the foreland basin system,we undertake to precisely analyze the model of structural evolution of the east Qiulitage.Based on precise seismic interpretation,salt rock triangular area analysis,surficial geology analysis,balanced profile analysis and drilled wells analysis,the structural type of the east Qiulitage is similar with that of Dabei-Keshen,which all present a ductile decollement imbricated thrust structure.The concrete thrust faulted anticline was developed in the east Qiulitage fault footwall.The oil and gas geological conditions of this area are superior after further comprehensive research.The sources are abundant,the anticline lies closely in the oil and gas forming centre and structural crest.It is a favourable area for oil and gas accumulation.The chief intended interval,Bashenjiqike Formation,present wide sandbodies of the braided delta front,just like Dabei-Keshen's.There are two sets of gypsum and salt rock for regional seals.So the east Qiulitage belt is the most favourable and actual area for exploration in Kuqa Depression.
Kuqa Depression is very important among the three oil and gas exploration zones in Tarim Basin.Continual important breakthroughs have been obtained in recent years,it has become a large oil and gas zone of 1×10~(12) m~3.But Qiulitage structural belt which lies in middle Kuqa Depression has still not significant stride,especially there is no commercial oil and gas flow in Cretaceous after three wells were drilled in the east Qiulitage.The main opinion of predecessors is that there are large anticlinal trap resulted from basement decollement,but now it is proved confinement for exploration.As a result,acquiring new geological viewpoint is a principal precondition for breakthroughs.Based on reprocess of seismic data,according to the theory of classification of the foreland basin system,we undertake to precisely analyze the model of structural evolution of the east Qiulitage.Based on precise seismic interpretation,salt rock triangular area analysis,surficial geology analysis,balanced profile analysis and drilled wells analysis,the structural type of the east Qiulitage is similar with that of Dabei-Keshen,which all present a ductile decollement imbricated thrust structure.The concrete thrust faulted anticline was developed in the east Qiulitage fault footwall.The oil and gas geological conditions of this area are superior after further comprehensive research.The sources are abundant,the anticline lies closely in the oil and gas forming centre and structural crest.It is a favourable area for oil and gas accumulation.The chief intended interval,Bashenjiqike Formation,present wide sandbodies of the braided delta front,just like Dabei-Keshen's.There are two sets of gypsum and salt rock for regional seals.So the east Qiulitage belt is the most favourable and actual area for exploration in Kuqa Depression.
引文
[1]Wang Zhaoming.Discussion of ceiling effect in foreland thrust belt of Kuqa Depression[J].Natural Gas Geoscience,2013,24(4):671-677.[王招明.试论库车前陆冲断带构造顶蓬效应[J].天然气地球科学,2013,24(4):671-677.]
[2]Wang Zhaoming,Formationmechanism and enrichment regularities of Kelasu subsalt deep large gas field in Kuqa Depression,Tarim Basin[J].Natural Gas Geoscience,2014,25(2):153-166.[王招明.塔里木盆地库车坳陷克拉苏盐下深层气田形成机制与富集规律[J].天然气地球科学,2014,25(2):153-166.]
[3]Liu Zhihong,Lu Huaxia,Jia Cheng Zao,et al.Orogeny timing and fault-slip rate and their significance to the rejuvenated foreland thrusts belt of Kuche[J].Petroleum Exploration and Development,2000,27(1):12-15.[刘志宏,卢华复,贾承造,等.库车再生前陆逆冲带造山运动时间、断层滑移速率的厘定及其意义[J].石油勘探与开发,2000,27(1):12-15.]
[4]Xu Zhenping,Xie Huiwen,Li Yong,et al.Characteristics and controlling factors of the subsalt differential structure in the Kelasu structural belt,Kuqa Depression[J].Natural Gas Geoscience,2012,23(6):1034-1038.[徐振平,谢会文,李勇,等.库车坳陷克拉苏构造带盐下差异构造变形特征及控制因素[J].天然气地球科学,2012,23(6):1034-1038.]
[5]Yu Haibo,Qi Jiafu,Shi Jun,et al.Basement fault activities have influenced on caprock tectonic deformation in Kuqa Depression[J].Chinese Journal of Geology,2015,50(1):50-62.[余海波,漆家福,师俊,等.库车坳陷盐下构造对盐上盖层变形的影响因素分析[J].地质科学,2015,50(1):50-62.]
[6]Jin Wenzheng,Tang Liangjie,Wang Qinghua,et al.Cenozoic tectonic evolution of the eastern Qiulitage structural belt,Kuqa forreland basin in Xinjiang[J].Chinese Journal of Geology,2007,42(3):444-454.[金文正,汤良杰,王清华,等.新疆库车盆地东秋里塔格构造带新生代的构造演化[J].地质科学,2007,42(3):444-454.]
[7]Yang Minghui,Jin Zhijun,LǚXiuxiang,et al.Structural characteristics and hydrocarbon accumulation of Kuche fold-thrust belts,Tarim Basin[J].Journal of Xi’an Shiyou University:Natural Science Edition,2004,19(1):1-4.[杨明慧,金之钧,吕修祥,等.塔里木盆地库车褶皱冲断带的构造特征与油气聚集[J].西安石油大学学报:自然科学版,2004,19(1):1-4.]
[8]Wu Zhenyun,Yin Hongwei,Wang Xin,et al.The Structural features and formation mechanism of exposed salt diapirs in the front of fold-thrust belt,western Kuqa Depression[J].Journal of Nanjing University:Natural Sciences,2015,51(3):612-625.[吴珍云,尹宏伟,汪新,等.库车坳陷西段褶皱—冲断带前缘盐底辟构造特征及形成机制[J].南京大学学报:自然科学,2015,51(3):612-625.]
[9]Miao Jijun,Jia Chengzao,Wang Zhaoming,et al.Structural segmentation and reservoir-formation along the Qiulitage anticline belt of Kuche thrust belt,Tarim Basin[J]。Petroleum Exploration and Development,2004,31(6):20-24.[苗继军,贾承造,王招明,等.秋里塔格构造带构造分段特征与油气成藏[J].石油勘探与开发,2004,31(6):20-24.]
[10]Li Feng,Jiang Zhenxue,Li Zhuo,et al.Palaeo-fluid evidence for the two-stage hydrocarbon charges in Dibei gas reservoir of Kuqa Depression[J].Natural Gas Geoscience,2014,25(7):1033-1041.[李峰,姜振学,李卓,等.库车坳陷迪北气藏2期油气充注古流体证据[J].天然气地球科学,2014,25(7):1033-1041.]
[11]Ma Yujie,Xie Huiwen,Cai Zhenzhong,et al.The geology feature of Dina 2 Gasfield,Kuche Depression[J].Natural Gas Geoscience,2003,14(5):371-374.[马玉杰,谢会文,蔡振忠,等.库车坳陷迪那2气田地质特征[J].天然气地球科学,2003,14(5):371-374.]
[12]Zhang Ronghu,Wang Junpeng,Ma Yujie,et al.The sedimentary microfacies palaeogeomorphology and their controls on gas accumulation of deep-buried cretaceous in Kuqa Depression,Tarim Basin,China[J].Natural Gas Geoscience,2015,26(4):667-678.[张荣虎,王俊鹏,马玉杰,等.塔里木盆地库车坳陷深层沉积微相古地貌及其对天然气富集的控制[J].天然气地球科学,2015,26(4):667-678.]
[2]Wang Zhaoming,Formationmechanism and enrichment regularities of Kelasu subsalt deep large gas field in Kuqa Depression,Tarim Basin[J].Natural Gas Geoscience,2014,25(2):153-166.[王招明.塔里木盆地库车坳陷克拉苏盐下深层气田形成机制与富集规律[J].天然气地球科学,2014,25(2):153-166.]
[3]Liu Zhihong,Lu Huaxia,Jia Cheng Zao,et al.Orogeny timing and fault-slip rate and their significance to the rejuvenated foreland thrusts belt of Kuche[J].Petroleum Exploration and Development,2000,27(1):12-15.[刘志宏,卢华复,贾承造,等.库车再生前陆逆冲带造山运动时间、断层滑移速率的厘定及其意义[J].石油勘探与开发,2000,27(1):12-15.]
[4]Xu Zhenping,Xie Huiwen,Li Yong,et al.Characteristics and controlling factors of the subsalt differential structure in the Kelasu structural belt,Kuqa Depression[J].Natural Gas Geoscience,2012,23(6):1034-1038.[徐振平,谢会文,李勇,等.库车坳陷克拉苏构造带盐下差异构造变形特征及控制因素[J].天然气地球科学,2012,23(6):1034-1038.]
[5]Yu Haibo,Qi Jiafu,Shi Jun,et al.Basement fault activities have influenced on caprock tectonic deformation in Kuqa Depression[J].Chinese Journal of Geology,2015,50(1):50-62.[余海波,漆家福,师俊,等.库车坳陷盐下构造对盐上盖层变形的影响因素分析[J].地质科学,2015,50(1):50-62.]
[6]Jin Wenzheng,Tang Liangjie,Wang Qinghua,et al.Cenozoic tectonic evolution of the eastern Qiulitage structural belt,Kuqa forreland basin in Xinjiang[J].Chinese Journal of Geology,2007,42(3):444-454.[金文正,汤良杰,王清华,等.新疆库车盆地东秋里塔格构造带新生代的构造演化[J].地质科学,2007,42(3):444-454.]
[7]Yang Minghui,Jin Zhijun,LǚXiuxiang,et al.Structural characteristics and hydrocarbon accumulation of Kuche fold-thrust belts,Tarim Basin[J].Journal of Xi’an Shiyou University:Natural Science Edition,2004,19(1):1-4.[杨明慧,金之钧,吕修祥,等.塔里木盆地库车褶皱冲断带的构造特征与油气聚集[J].西安石油大学学报:自然科学版,2004,19(1):1-4.]
[8]Wu Zhenyun,Yin Hongwei,Wang Xin,et al.The Structural features and formation mechanism of exposed salt diapirs in the front of fold-thrust belt,western Kuqa Depression[J].Journal of Nanjing University:Natural Sciences,2015,51(3):612-625.[吴珍云,尹宏伟,汪新,等.库车坳陷西段褶皱—冲断带前缘盐底辟构造特征及形成机制[J].南京大学学报:自然科学,2015,51(3):612-625.]
[9]Miao Jijun,Jia Chengzao,Wang Zhaoming,et al.Structural segmentation and reservoir-formation along the Qiulitage anticline belt of Kuche thrust belt,Tarim Basin[J]。Petroleum Exploration and Development,2004,31(6):20-24.[苗继军,贾承造,王招明,等.秋里塔格构造带构造分段特征与油气成藏[J].石油勘探与开发,2004,31(6):20-24.]
[10]Li Feng,Jiang Zhenxue,Li Zhuo,et al.Palaeo-fluid evidence for the two-stage hydrocarbon charges in Dibei gas reservoir of Kuqa Depression[J].Natural Gas Geoscience,2014,25(7):1033-1041.[李峰,姜振学,李卓,等.库车坳陷迪北气藏2期油气充注古流体证据[J].天然气地球科学,2014,25(7):1033-1041.]
[11]Ma Yujie,Xie Huiwen,Cai Zhenzhong,et al.The geology feature of Dina 2 Gasfield,Kuche Depression[J].Natural Gas Geoscience,2003,14(5):371-374.[马玉杰,谢会文,蔡振忠,等.库车坳陷迪那2气田地质特征[J].天然气地球科学,2003,14(5):371-374.]
[12]Zhang Ronghu,Wang Junpeng,Ma Yujie,et al.The sedimentary microfacies palaeogeomorphology and their controls on gas accumulation of deep-buried cretaceous in Kuqa Depression,Tarim Basin,China[J].Natural Gas Geoscience,2015,26(4):667-678.[张荣虎,王俊鹏,马玉杰,等.塔里木盆地库车坳陷深层沉积微相古地貌及其对天然气富集的控制[J].天然气地球科学,2015,26(4):667-678.]