川西坳陷中段雷口坡组烃源岩评价及气源分析
|
摘要
在对川西坳陷中段雷口坡组烃源岩评价基础上,结合雷口坡组天然气地球化学特征与成藏地质条件分析,探讨了该区不同构造带雷口坡组天然气的气源及差异。烃源岩分析表明:该区雷口坡组烃源岩有机质类型为Ⅱ型,R_o大于2%,但有机质丰度偏低,w(TOC)平均值普遍低于0.3%,普遍未达到有效烃源岩,能为雷口坡组提供的气源非常有限。天然气组分分析显示:新场构造带雷口坡组天然气更富烃类组分,不含或含微量H_2S,而龙门山前构造带雷口坡组天然气更富非烃组分,天然气中H_2S体积分数为3.50%～9.97%,平均值为4.91%,属高含H_2S气藏。受雷口坡组烃源岩生烃有限与雷口坡组多套膏盐层封堵的影响,新场构造带雷口坡组天然气主要来自上覆须家河组烃源岩。龙门山前构造带雷口坡组气藏得益于沟通下伏海相层系的断裂与下伏发育的多套优质烃源岩,下伏海相层系为该区雷口坡组气藏提供了主要的气源。两构造带气源的差异导致了天然气组分特征的显著差异。
This paper discusses the source of the natural gas of Leikoupo Formation in the middle part of West Sichuan Depression based on the research of source rocks and geochemical characteristics and accumulation conditions of natural gas. The formation source rock analysis shows that organic type is type II,with R_o value greater than 2%. But the organic abundance is too low, with the TOC value generally less than 0.3%. Accordingly, the source rocks generally are not effective source rocks and cannot provide enough gas for Leikoupu Formation reservoir. The research of component of Leikoupo Formation natural gas shows that the gas in the Xinchang tectonic belt is more enriched in hydrocarbon and contains no or trace of H_2S. But in the Longmenshan piedmont tectonic belt, the natural gas is more enriched in nonhydrocarbon, with H_2S content ranging from 3.50% to 9.97% and averaged at 4.91%, thus illustrating that the gas reservoir is a high H_2S gas reservoir. Influenced by the limited hydrocarbon generation of the source rocks of the Leikoupo Formation and the blocking of multiple layers of the gypsum salt in the Leikoupo Formation, the natural gas of the Leikoupo Formation in the Xinchang tectonic belt is mainly from the source rocks of the uplap Xujiahe Formation. Because there are many faults connecting the underlying marine strata and sets of high quality source rocks, the underlying marine source rocks provide the main gas for the Leikoupo Formation gas reservoir in the Longmenshan piedmont tectonic belt. The dfferent gas sources are the main reason for the difference of natural gas components.
This paper discusses the source of the natural gas of Leikoupo Formation in the middle part of West Sichuan Depression based on the research of source rocks and geochemical characteristics and accumulation conditions of natural gas. The formation source rock analysis shows that organic type is type II,with R_o value greater than 2%. But the organic abundance is too low, with the TOC value generally less than 0.3%. Accordingly, the source rocks generally are not effective source rocks and cannot provide enough gas for Leikoupu Formation reservoir. The research of component of Leikoupo Formation natural gas shows that the gas in the Xinchang tectonic belt is more enriched in hydrocarbon and contains no or trace of H_2S. But in the Longmenshan piedmont tectonic belt, the natural gas is more enriched in nonhydrocarbon, with H_2S content ranging from 3.50% to 9.97% and averaged at 4.91%, thus illustrating that the gas reservoir is a high H_2S gas reservoir. Influenced by the limited hydrocarbon generation of the source rocks of the Leikoupo Formation and the blocking of multiple layers of the gypsum salt in the Leikoupo Formation, the natural gas of the Leikoupo Formation in the Xinchang tectonic belt is mainly from the source rocks of the uplap Xujiahe Formation. Because there are many faults connecting the underlying marine strata and sets of high quality source rocks, the underlying marine source rocks provide the main gas for the Leikoupo Formation gas reservoir in the Longmenshan piedmont tectonic belt. The dfferent gas sources are the main reason for the difference of natural gas components.
引文
[1] 谢刚平,叶素娟,田苗.川西坳陷致密砂岩气藏勘探开发实践新认识[J].天然气工业,2014,34(1):44-53.
[2] 叶军.川西海相天然气勘探难点及对策[J].天然气工业,2008,28(2):17-22.
[3] 谢刚平.川西坳陷中三叠统雷口坡组四段气藏气源分析[J].石油实验地质,2015,37(4):418-429.
[4] 李书兵,许国明,宋晓波.川西龙门山前构造带彭州雷口坡组大型气田的形成条件[J].中国石油勘探,2016,21(3):74-82.
[5] 孟昱璋,徐国盛,刘勇,等.川西雷口坡组古风化壳喀斯特气藏成藏条件[J].成都理工大学学报:自然科学版,2015,42(1):70-79.
[6] 宋晓波,刘诗荣,王琼仙,等.川西坳陷西缘中下三叠统油气成藏主控因素[J].岩性油气藏,2011,23(1):67-72.
[7] 王鹏,沈忠民,刘四兵,等.川西坳陷天然气中烷烃气碳同位素倒转成因分析[J].地质科技情报,2014,33(1):137-143.
[8] 唐宇.川西地区雷口坡组沉积与其顶部风化壳储层特征[J].石油与天然气地质,2013,34(1):42-47.
[9] 吴世祥,李宏涛,龙胜祥,等.川西雷口坡组碳酸盐岩储层特征及成岩作用[J].石油与天然气地质,2011,32(4):542-550.
[10] 许国明,宋晓波,冯霞,等.川西地区中三叠统雷口坡组天然气勘探潜力[J].天然气工业,2013,33(8):8-14.
[11] 杨克明.四川盆地西部中三叠统雷口坡组烃源岩生烃潜力分析[J].石油实验地质,2016,38(3):366-374.
[12] 梁狄刚,张水昌,张宝民,等.从塔里木盆地看中国海相生油问题[J].地学前缘,2000,7(4):534-547.
[13] 张水昌,梁狄刚,张大江.关于古生界烃源岩有机质丰度的评价标准[J].石油勘探与开发,2002,29(2):8-12.
[14] 陈建平,梁狄刚,张水昌,等.中国古生界海相烃源岩生烃潜力评价标准与方法[J].地质学报,2012,86(7):1132-1142.
[15] 薛海涛,卢双舫,钟宁宁.碳酸盐岩气源岩有机质丰度下限研究[J].中国科学:地球科学,2004,34(增刊1):127-133.
[16] 刘宝泉,梁狄刚,方杰,等.华北地区中上元古界-下古生界碳酸盐岩有机质成熟度与找油远景[J].地球化学,1985,14(2):150-162.
[17] 彭平安,刘大永,秦艳,等.海相碳酸盐岩烃源岩评价的有机碳下限问题[J].地球化学,2008,37(4):415-422.
[18] 饶丹,章平澜,邱蕴玉.有效烃源岩下限指标初探[J].石油实验地质,2003,25(增刊1):578-581.
[19] 王兰生,李子荣,谢姚祥,等.川西南地区二叠系碳酸盐岩生烃下限研究[J].天然气地球科学,2003,14(1):39-46.
[20] 秦建中,刘宝泉,国建英,等.关于碳酸盐烃源岩的评价标准[J].石油实验地质,2004,26(3):281-286.
[21] 戴金星.中国含硫化氢的天然气分布特征、分类及其成因探讨[J].沉积学报,1985,3(4):109-120.
[22] 叶军.川西坳陷马鞍塘组-须二段天然气成矿系统烃源岩评价[J].天然气工业,2003,23(1):21-25.
[23] 米色子哈.川西坳陷中段中三叠统雷口坡组储层特征[D].成都:成都理工大学,2012.
[24] 徐国盛,刘中平.川西地区上三叠统地层古压力形成与演化的数值模拟[J].石油实验地质,1996,18(1):117-126.
[25] 许国明.川西地区中古生界海相油气地质条件研究[D].成都:成都理工大学,2010.
[26] 秦川.川西坳陷中北部三叠系雷口坡组-马鞍塘组储层特征及油气勘探前景[D].成都:成都理工大学,2012.
[27] 朱光有,张水昌,梁英波,等.川东北飞仙关组高含H2S气藏特征与TSR对烃类的消耗作用[J].沉积学报,2006,24(2):300-308.
[28] 焦伟伟,李建交,田磊.中国海相碳酸盐岩优质储层形成的地质条件[J].地质科技情报,2009,28(6):64-70.
[29] 黄士鹏,廖凤蓉,吴小奇,等.四川盆地含硫化氢气藏分布特征及硫化氢成因探讨[J].天然气地球科学,2010,21(5):705-714.
[30] 戴金星,倪云燕,邹才能,等.四川盆地须家河组煤系烷烃气碳同位素特征及气源对比意义[J].石油与天然气地质,2009,30(5):519-529.
[31] 王鹏,沈忠民,刘四兵,等.四川盆地陆相天然气地球化学特征及对比[J].天然气地球科学,2013,24(6):1186-1195.
[2] 叶军.川西海相天然气勘探难点及对策[J].天然气工业,2008,28(2):17-22.
[3] 谢刚平.川西坳陷中三叠统雷口坡组四段气藏气源分析[J].石油实验地质,2015,37(4):418-429.
[4] 李书兵,许国明,宋晓波.川西龙门山前构造带彭州雷口坡组大型气田的形成条件[J].中国石油勘探,2016,21(3):74-82.
[5] 孟昱璋,徐国盛,刘勇,等.川西雷口坡组古风化壳喀斯特气藏成藏条件[J].成都理工大学学报:自然科学版,2015,42(1):70-79.
[6] 宋晓波,刘诗荣,王琼仙,等.川西坳陷西缘中下三叠统油气成藏主控因素[J].岩性油气藏,2011,23(1):67-72.
[7] 王鹏,沈忠民,刘四兵,等.川西坳陷天然气中烷烃气碳同位素倒转成因分析[J].地质科技情报,2014,33(1):137-143.
[8] 唐宇.川西地区雷口坡组沉积与其顶部风化壳储层特征[J].石油与天然气地质,2013,34(1):42-47.
[9] 吴世祥,李宏涛,龙胜祥,等.川西雷口坡组碳酸盐岩储层特征及成岩作用[J].石油与天然气地质,2011,32(4):542-550.
[10] 许国明,宋晓波,冯霞,等.川西地区中三叠统雷口坡组天然气勘探潜力[J].天然气工业,2013,33(8):8-14.
[11] 杨克明.四川盆地西部中三叠统雷口坡组烃源岩生烃潜力分析[J].石油实验地质,2016,38(3):366-374.
[12] 梁狄刚,张水昌,张宝民,等.从塔里木盆地看中国海相生油问题[J].地学前缘,2000,7(4):534-547.
[13] 张水昌,梁狄刚,张大江.关于古生界烃源岩有机质丰度的评价标准[J].石油勘探与开发,2002,29(2):8-12.
[14] 陈建平,梁狄刚,张水昌,等.中国古生界海相烃源岩生烃潜力评价标准与方法[J].地质学报,2012,86(7):1132-1142.
[15] 薛海涛,卢双舫,钟宁宁.碳酸盐岩气源岩有机质丰度下限研究[J].中国科学:地球科学,2004,34(增刊1):127-133.
[16] 刘宝泉,梁狄刚,方杰,等.华北地区中上元古界-下古生界碳酸盐岩有机质成熟度与找油远景[J].地球化学,1985,14(2):150-162.
[17] 彭平安,刘大永,秦艳,等.海相碳酸盐岩烃源岩评价的有机碳下限问题[J].地球化学,2008,37(4):415-422.
[18] 饶丹,章平澜,邱蕴玉.有效烃源岩下限指标初探[J].石油实验地质,2003,25(增刊1):578-581.
[19] 王兰生,李子荣,谢姚祥,等.川西南地区二叠系碳酸盐岩生烃下限研究[J].天然气地球科学,2003,14(1):39-46.
[20] 秦建中,刘宝泉,国建英,等.关于碳酸盐烃源岩的评价标准[J].石油实验地质,2004,26(3):281-286.
[21] 戴金星.中国含硫化氢的天然气分布特征、分类及其成因探讨[J].沉积学报,1985,3(4):109-120.
[22] 叶军.川西坳陷马鞍塘组-须二段天然气成矿系统烃源岩评价[J].天然气工业,2003,23(1):21-25.
[23] 米色子哈.川西坳陷中段中三叠统雷口坡组储层特征[D].成都:成都理工大学,2012.
[24] 徐国盛,刘中平.川西地区上三叠统地层古压力形成与演化的数值模拟[J].石油实验地质,1996,18(1):117-126.
[25] 许国明.川西地区中古生界海相油气地质条件研究[D].成都:成都理工大学,2010.
[26] 秦川.川西坳陷中北部三叠系雷口坡组-马鞍塘组储层特征及油气勘探前景[D].成都:成都理工大学,2012.
[27] 朱光有,张水昌,梁英波,等.川东北飞仙关组高含H2S气藏特征与TSR对烃类的消耗作用[J].沉积学报,2006,24(2):300-308.
[28] 焦伟伟,李建交,田磊.中国海相碳酸盐岩优质储层形成的地质条件[J].地质科技情报,2009,28(6):64-70.
[29] 黄士鹏,廖凤蓉,吴小奇,等.四川盆地含硫化氢气藏分布特征及硫化氢成因探讨[J].天然气地球科学,2010,21(5):705-714.
[30] 戴金星,倪云燕,邹才能,等.四川盆地须家河组煤系烷烃气碳同位素特征及气源对比意义[J].石油与天然气地质,2009,30(5):519-529.
[31] 王鹏,沈忠民,刘四兵,等.四川盆地陆相天然气地球化学特征及对比[J].天然气地球科学,2013,24(6):1186-1195.