济阳坳陷深层裂解气成因鉴别及其成藏差异性
|
摘要
济阳坳陷深层裂解气藏成因较为复杂,影响了深层天然气的认识和勘探。利用天然气组分和碳同位素等鉴别了原油裂解气和干酪根裂解气,进一步分析了2类成因的成藏差异性。原油裂解气表现为Ln(C2/C3)值随Ln(C1/C2)值增大而增大;干酪根裂解气随Ln(C1/C2)值的增大,Ln(C2/C3)值基本不变。在有机质类型和热演化程度大致相当的情况下,原油裂解气δ13C1值、δ13C2值、δ13C3值与相应的干酪根裂解气的最大差值分别为-12.4‰、-8.8‰和7.5‰;随着δ13C1值或(δ13C1-δ13C2)值的增大,干酪根裂解气(δ13 C2-δ13 C3)值快速减小,而裂解气(δ13 C2-δ13 C3)值变化微弱。干酪根裂解气藏表现为早期油气扩散、断裂活动停止和后期天然气充注,原油裂解气藏体现为早期油气充注、岩性侧向封堵和后期古油藏裂解的成藏规律。2种裂解气成因开启了深层天然气勘探的新思路,并指出了其勘探方向,对深层勘探具有重要的指导意义。
The origin of cracking gas in the deep buried horizons is very complicated,and it is one of the main limits for gas exploration in Jiyang Depression.Based on gas component and carbon isotope analysis,it is possible to distinguish between oil cracking gas and kerogen cracking gas.Oil cracking gas is featured by ln(C2/C3)increasing with ln(C1/C2);but as for kerogen cracking gas,ln(C2/C3)was almost constant despite of the increase of ln(C1/C2).When the organic matter type is the same and thermal maturity is similar,the difference ofδ13C1,δ13C2,andδ13C3between oil cracking gas and kerogen cracking gas can be up to-12.4‰,-8.8‰and 7.5‰,respectively.With the increase ofδ13C1or(δ13C1-δ13C2),(δ13C2-δ13C3)of kerogen cracking gas decreased rapidly,while that value of oil cracking gas are almost constant.This study also demonstrated the differences in gas accumulation between these two kinds of gas reservoir.As for kerogen cracking gas,fault activities damaged oil and gas reservoir that formed in early period,and gas reservoir formed in lithologic traps in low lying structural belt during late period when fault activity stopped.As for oil cracking gas,oil and gas accumulated in early period sealed by lithology difference,and oil cracked in late period to form cracking gas reservoir.Understanding in the origin of the two kinds of cracking gas reservoir opened a new concept in gas exploration,and this is significant for exploration in deep buried horizons.
The origin of cracking gas in the deep buried horizons is very complicated,and it is one of the main limits for gas exploration in Jiyang Depression.Based on gas component and carbon isotope analysis,it is possible to distinguish between oil cracking gas and kerogen cracking gas.Oil cracking gas is featured by ln(C2/C3)increasing with ln(C1/C2);but as for kerogen cracking gas,ln(C2/C3)was almost constant despite of the increase of ln(C1/C2).When the organic matter type is the same and thermal maturity is similar,the difference ofδ13C1,δ13C2,andδ13C3between oil cracking gas and kerogen cracking gas can be up to-12.4‰,-8.8‰and 7.5‰,respectively.With the increase ofδ13C1or(δ13C1-δ13C2),(δ13C2-δ13C3)of kerogen cracking gas decreased rapidly,while that value of oil cracking gas are almost constant.This study also demonstrated the differences in gas accumulation between these two kinds of gas reservoir.As for kerogen cracking gas,fault activities damaged oil and gas reservoir that formed in early period,and gas reservoir formed in lithologic traps in low lying structural belt during late period when fault activity stopped.As for oil cracking gas,oil and gas accumulated in early period sealed by lithology difference,and oil cracked in late period to form cracking gas reservoir.Understanding in the origin of the two kinds of cracking gas reservoir opened a new concept in gas exploration,and this is significant for exploration in deep buried horizons.
引文
[1]Wang Wenlin.Formation conditions of deep-seated condensate gas reservoir in the Paleogene in Dongying Sag[J].Petroleum Geology and Recovery Efficiency,2007,14(3):55-57.[王文林.东营凹陷古近系深层凝析气藏形成条件[J].油气地质与采收率,2007,14(3):55-57.]
[2]Li Xiaojun,Li Wentao,Zhang Haijun.Cracking gas reservoirforming analysis and exploration orientation in Jiyang Depression[J].Petroleum Geology and Recovery Efficiency,2005,12(1):42-45.[李孝军,李文涛,张海君.济阳坳陷裂解气成藏条件及勘探方向[J].油气地质与采收率,2005,12(1):42-45.]
[3]Yang Xiancheng,Sui Fenggui.The main controlling factors of deep cracked gas accumulation in Dongying Sag[J].Xinjiang Petroleum Geology,2007,28(5):363-565.[杨显成,隋风贵.东营凹陷深层裂解气成藏主控因素[J].新疆石油地质,2007,28(5):363-565.]
[4]Wang Li,Jin Qiang,Lin Lamei,et al.The geochemical characteristics of nature gas and discussion on gas source in Bogu 4buried hill[J].Natural Gas Geoscience,2007,18(5):715-719.[王力,金强,林腊梅,等.济阳坳陷孤北—渤南地区渤古4潜山天然气地球化学特征及气源探讨[J].天然气地球科学,2007,18(5):715-719.]
[5]Song Mingshui,Zhang Xuecai.Discussion on deep gas geochemical characteristics and genesis of Bonan sag in Jiyang Depression[J].Natural Gas Geoscience,2004,15(6):646-649.[宋明水,张学才.济阳坳陷渤南深层天然气的地球化学特征及成因探讨[J].天然气地球科学,2004,15(6):646-649.]
[6]Li Yanjun,Song Guoqi,Li Wentao,et al.A fossil oil reservoir and the gas origin in the Lower Sha-4 member of the well Fengshen 1area,the north Dongying zone of the Jiyang Depression[J].Oil&Gas Geology,2010,31(2):173-179.[李延军,宋国奇,李文涛,等.济阳坳陷东营凹陷北带丰深1井区深层沙四下古油藏与天然气成因[J].石油与天然气地质,2010,31(2):173-179.]
[7]Chen Rongshu.Natural Gas Geology[M].Wuhan:China University of Geosciences Press,1989.[陈荣书.天然气地质学[M].武汉:中国地质大学出版社,1989.]
[8]Li Xiangchen.Study on effective hydrocarbon source rocks and relationship between them and nature gas reservoirs[J].Natural Gas Geoscience,2003,14(1):53-56.[李祥臣.有效气源岩及其与天然气藏的关系探讨[J].天然气地球科学,2003,14(1):53-56.]
[9]Zhu Guangyou,Jin Qiang,Zhang Shanwen,et al.Salt lake-saline lake sedimentary combination and petroleum accumulation in the Bonan Sag[J].Acta Mineralogica Sinica,2004,24(1):25-30.[朱光有,金强,张善文,等.渤南洼陷盐湖—咸水湖沉积组合及其油气聚集[J].矿物学报,2004,24(1):25-30.]
[10]Wang Juan,Jin Qiang,Ma Guozheng,et al.Catalytic action of sulphate evaporates in pyrolytic gas generation of source rocks[J].Natural Gas Geoscience,2009,20(1):26-31.[王娟,金强,马国政,等.高成熟阶段膏岩等盐类物质在烃源岩热解生烃过程中的催化作用[J].天然气地球科学,2009,20(1):26-31.]
[11]Yuan Dongshan,Zhang Zhihuan,Zeng Yantao,et al.Organic matter types and organic facies of source rocks in the 4th member of Shahejie Formation in Bonan Sub-sag Zhanhua Sag[J].Natural Gas Geoscience,2006,17(1):125-128.[袁东山,张枝焕,曾艳涛,等.沾化凹陷渤南洼陷沙四段烃源岩有机相[J].天然气地球科学,2006,17(1):125-128.]
[12]Ren Yongjun,Zhou Yaoqi,Zha Ming,et al.Maturity of Lower Tertiary source rocks in Dongying Depression[J].Journal of China University of Petroleum:Edition of Natural Science,2006,30(2):6-10.[任拥军,周瑶琪,查明,等.东营凹陷古近系烃源岩成熟度特征[J].中国石油大学学报:自然科学版,2006,30(2):6-10.]
[13]Behar F,Kressmann S.Experimental simulation in Confined system and kinetic modeling of kerogen and oil cracking[J].Organic Geochemistry,1991,19(19):173-189.
[14]Prinzhofer A,Alain Y.Genetic and post-genetic molecular and isotopic fractionations in natural gases[J].Chemical Geology,1995,126(3):281-290
[15]Chen Shijia,Fu Xiaowen,Ma Lining,et al.Genetic identification method of kerogen-cracked gases oil-cracked gases[J].Experimental Petroleum Geology,2002,24(4):364-366.[陈世加,付晓文,马力宁,等.干酪根裂解气和原油裂解气的成因判识方法[J].石油实验地质,2002,24(4):364-366.]
[16]Wang Zhenping,Fu Xiaotai,Lu Shuangfang,et al.An analogue experiment of gas generating by crude oil cracking,Characters of products and its significance[J].Natural Gas Industry,2001,21(3):12-15.[王振平,付晓泰,卢双舫,等.原油裂解成气模拟实验、产物特征及其意义[J].天然气工业,2001,21(3):12-15.]
[17]Zhao Mengjun,Zeng Fangang,Qin Shengfei,et al.Two pyrolytic gases found and proved in Talimu Basin[J].Natural Gas Industry,2001,21(1):35-39.[赵孟军,曾凡刚,秦胜飞,等.塔里木发现和证实两种裂解气[J].天然气工业,2001,21(1):35-39.]
[18]Zhao Wenzhi,Wang Zecheng,Wang Yigang,et al.Formation mechanism of highly effective gas pools in the Feixianguan Formation in the NE Sichuan Basin[J].Geological Review,2006,52(5):708-718.[赵文智,汪泽成,王一刚,等.四川盆地东北部飞仙关组高效气藏形成机理[J].地质论评,2006,52(5):708-718.]
[19]Gao Shengjun,Chen Yicai,Li Yanjun,et al.Pyrolysis on crude oil and characteristics of Sha 4member cracking gas,Dongying Depression[J].Natural Gas Geoscience,2009,20(1):32-35.[高生军,陈义才,李延军,等.东营凹陷沙四段原油裂解热模拟及产物特征[J].天然气地质科学,2009,20(1):32-35.]
[20]Tian Hui,Xiao Xianming,Li Xianqing,et al.Comparison of gas generation and carbon isotope fractionation of methane from marine kerogen-and crude oil-cracking gases[J].Geochimica,2007,36(1):71-76.[田辉,肖贤明,李贤庆,等.海相干酪根与原油裂解气甲烷生成及碳同位素分馏的差异研究[J].地球化学,2007,36(1):71-76.]
[21]Zhao Wenzhi,Wang Zhaoyun,Zhang Shuichang,et al.Successive generation of natural gas from organic materials and its significance in future exploration[J].Petroleum Exploration and Development,2005,32(2):1-7.[赵文智,王兆云,张水昌,等.有机质“接力生气”模式的提出及其在勘探中的意义[J].石油勘探与开发,2005,32(2):1-7.]
[2]Li Xiaojun,Li Wentao,Zhang Haijun.Cracking gas reservoirforming analysis and exploration orientation in Jiyang Depression[J].Petroleum Geology and Recovery Efficiency,2005,12(1):42-45.[李孝军,李文涛,张海君.济阳坳陷裂解气成藏条件及勘探方向[J].油气地质与采收率,2005,12(1):42-45.]
[3]Yang Xiancheng,Sui Fenggui.The main controlling factors of deep cracked gas accumulation in Dongying Sag[J].Xinjiang Petroleum Geology,2007,28(5):363-565.[杨显成,隋风贵.东营凹陷深层裂解气成藏主控因素[J].新疆石油地质,2007,28(5):363-565.]
[4]Wang Li,Jin Qiang,Lin Lamei,et al.The geochemical characteristics of nature gas and discussion on gas source in Bogu 4buried hill[J].Natural Gas Geoscience,2007,18(5):715-719.[王力,金强,林腊梅,等.济阳坳陷孤北—渤南地区渤古4潜山天然气地球化学特征及气源探讨[J].天然气地球科学,2007,18(5):715-719.]
[5]Song Mingshui,Zhang Xuecai.Discussion on deep gas geochemical characteristics and genesis of Bonan sag in Jiyang Depression[J].Natural Gas Geoscience,2004,15(6):646-649.[宋明水,张学才.济阳坳陷渤南深层天然气的地球化学特征及成因探讨[J].天然气地球科学,2004,15(6):646-649.]
[6]Li Yanjun,Song Guoqi,Li Wentao,et al.A fossil oil reservoir and the gas origin in the Lower Sha-4 member of the well Fengshen 1area,the north Dongying zone of the Jiyang Depression[J].Oil&Gas Geology,2010,31(2):173-179.[李延军,宋国奇,李文涛,等.济阳坳陷东营凹陷北带丰深1井区深层沙四下古油藏与天然气成因[J].石油与天然气地质,2010,31(2):173-179.]
[7]Chen Rongshu.Natural Gas Geology[M].Wuhan:China University of Geosciences Press,1989.[陈荣书.天然气地质学[M].武汉:中国地质大学出版社,1989.]
[8]Li Xiangchen.Study on effective hydrocarbon source rocks and relationship between them and nature gas reservoirs[J].Natural Gas Geoscience,2003,14(1):53-56.[李祥臣.有效气源岩及其与天然气藏的关系探讨[J].天然气地球科学,2003,14(1):53-56.]
[9]Zhu Guangyou,Jin Qiang,Zhang Shanwen,et al.Salt lake-saline lake sedimentary combination and petroleum accumulation in the Bonan Sag[J].Acta Mineralogica Sinica,2004,24(1):25-30.[朱光有,金强,张善文,等.渤南洼陷盐湖—咸水湖沉积组合及其油气聚集[J].矿物学报,2004,24(1):25-30.]
[10]Wang Juan,Jin Qiang,Ma Guozheng,et al.Catalytic action of sulphate evaporates in pyrolytic gas generation of source rocks[J].Natural Gas Geoscience,2009,20(1):26-31.[王娟,金强,马国政,等.高成熟阶段膏岩等盐类物质在烃源岩热解生烃过程中的催化作用[J].天然气地球科学,2009,20(1):26-31.]
[11]Yuan Dongshan,Zhang Zhihuan,Zeng Yantao,et al.Organic matter types and organic facies of source rocks in the 4th member of Shahejie Formation in Bonan Sub-sag Zhanhua Sag[J].Natural Gas Geoscience,2006,17(1):125-128.[袁东山,张枝焕,曾艳涛,等.沾化凹陷渤南洼陷沙四段烃源岩有机相[J].天然气地球科学,2006,17(1):125-128.]
[12]Ren Yongjun,Zhou Yaoqi,Zha Ming,et al.Maturity of Lower Tertiary source rocks in Dongying Depression[J].Journal of China University of Petroleum:Edition of Natural Science,2006,30(2):6-10.[任拥军,周瑶琪,查明,等.东营凹陷古近系烃源岩成熟度特征[J].中国石油大学学报:自然科学版,2006,30(2):6-10.]
[13]Behar F,Kressmann S.Experimental simulation in Confined system and kinetic modeling of kerogen and oil cracking[J].Organic Geochemistry,1991,19(19):173-189.
[14]Prinzhofer A,Alain Y.Genetic and post-genetic molecular and isotopic fractionations in natural gases[J].Chemical Geology,1995,126(3):281-290
[15]Chen Shijia,Fu Xiaowen,Ma Lining,et al.Genetic identification method of kerogen-cracked gases oil-cracked gases[J].Experimental Petroleum Geology,2002,24(4):364-366.[陈世加,付晓文,马力宁,等.干酪根裂解气和原油裂解气的成因判识方法[J].石油实验地质,2002,24(4):364-366.]
[16]Wang Zhenping,Fu Xiaotai,Lu Shuangfang,et al.An analogue experiment of gas generating by crude oil cracking,Characters of products and its significance[J].Natural Gas Industry,2001,21(3):12-15.[王振平,付晓泰,卢双舫,等.原油裂解成气模拟实验、产物特征及其意义[J].天然气工业,2001,21(3):12-15.]
[17]Zhao Mengjun,Zeng Fangang,Qin Shengfei,et al.Two pyrolytic gases found and proved in Talimu Basin[J].Natural Gas Industry,2001,21(1):35-39.[赵孟军,曾凡刚,秦胜飞,等.塔里木发现和证实两种裂解气[J].天然气工业,2001,21(1):35-39.]
[18]Zhao Wenzhi,Wang Zecheng,Wang Yigang,et al.Formation mechanism of highly effective gas pools in the Feixianguan Formation in the NE Sichuan Basin[J].Geological Review,2006,52(5):708-718.[赵文智,汪泽成,王一刚,等.四川盆地东北部飞仙关组高效气藏形成机理[J].地质论评,2006,52(5):708-718.]
[19]Gao Shengjun,Chen Yicai,Li Yanjun,et al.Pyrolysis on crude oil and characteristics of Sha 4member cracking gas,Dongying Depression[J].Natural Gas Geoscience,2009,20(1):32-35.[高生军,陈义才,李延军,等.东营凹陷沙四段原油裂解热模拟及产物特征[J].天然气地质科学,2009,20(1):32-35.]
[20]Tian Hui,Xiao Xianming,Li Xianqing,et al.Comparison of gas generation and carbon isotope fractionation of methane from marine kerogen-and crude oil-cracking gases[J].Geochimica,2007,36(1):71-76.[田辉,肖贤明,李贤庆,等.海相干酪根与原油裂解气甲烷生成及碳同位素分馏的差异研究[J].地球化学,2007,36(1):71-76.]
[21]Zhao Wenzhi,Wang Zhaoyun,Zhang Shuichang,et al.Successive generation of natural gas from organic materials and its significance in future exploration[J].Petroleum Exploration and Development,2005,32(2):1-7.[赵文智,王兆云,张水昌,等.有机质“接力生气”模式的提出及其在勘探中的意义[J].石油勘探与开发,2005,32(2):1-7.]