克深气田巴什基奇克组致密砂岩储层孔隙结构特征及影响因素分析
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摘要
塔里木盆地库车坳陷克深气田巴什基奇克组埋藏深度主要为6 000～8 500m,岩石致密,为典型的超深致密砂岩储层。应用普通薄片、铸体薄片观察,扫描电镜、激光共聚焦显微镜、场发射扫描电镜分析和恒速压汞、核磁共振、离心等实验资料,研究其储层岩石学和孔隙结构特征,并从构造、沉积、成岩等地质角度入手,探讨影响孔隙结构的因素。结果表明,储层岩性主要为长石岩屑砂岩及岩屑砂岩,成分成熟度及结构成熟度中等;储集空间以原生粒间孔为主,粒内溶孔、粒间溶孔次之,存在微裂隙,孔隙结构复杂,属于裂缝-孔隙型致密砂岩储层;根据离心前后核磁共振T_2谱图(T_e=0.2ms)形态对比特征及束缚水饱和度的不同,可将储层分为3类,Ⅰ类储层占样品数的35%,为大孔隙占优,离心后束缚水饱和度约为25%;Ⅱ类储层占样品数的20%,大、小孔隙相当,离心后束缚水饱和度约为45%;Ⅲ类储层占样品数的45%,以小孔隙为主,束缚水饱和度平均高达50%;成岩作用是影响储层孔隙结构的主要因素,沉积作用是影响孔隙结构的先决条件,而后期的构造应力作用产生的侧向挤压应力和微裂隙则是孔隙结构复杂化的重要因素。
The Bashijiqike Formation in Keshen Gasfield of Kuqa Depression,Tarim Basin is a typical ultradeep tight sandstone reservoir with the burial depth mainly at 6 000-8 500 m,whose rock is compact.By using the experimental data such as normal and casting thin sections observation,scanning electron microscopy,laser confocal microscopy,field emission electron microscopy,rate-controlled porosimetry,nuclear magnetic resonance,and centrifugation,this paper studies the petrological and pore structure characteristics of Bashijiqike sandstone reservoir.At the same time,the paper discusses the factors influencing the pore structure from the geological point of view of structure,sedimentation and diagenesis.The results show that the reservoir lithology is mainly feldspar lithic sandstone,and the composition maturity and structure maturity are moderate.The reservoir space is dominated by intergranular pores,followed by the intragranular dissolution and the intergranular dissolution,and then microfratures.Hence,the pore structure is complex and belongs to the fractured-pore type sandstone reservoir.According to the differences of the morphological characteristics of the nuclear magnetic resonance T_2 spectrum(T_e=0.2 ms)before and after centrifugation and the irreducible water saturation,the reservoir can be divided into three categories.The macropores dominate in the first category reservoir,taking up 35% of the samples mainly,in which irreducible water saturation is 25% after centrifugation;the macropores and micropores are fairly typical for the second category reservoir,taking up 20% of the samples,in which irreducible water saturation is 45% after centrifugation;the micropores dominatein the third category reservoir,taking up 45% of the samples,in which irreducible water saturation is 50%after centrifugation.Diagenesis is the main factor affecting the pore structure of reservoir and sedimentation is a prerequisite for pore structure and the microfracture produced by the later tectonic stress is an important factor forthe complex pore structure.
The Bashijiqike Formation in Keshen Gasfield of Kuqa Depression,Tarim Basin is a typical ultradeep tight sandstone reservoir with the burial depth mainly at 6 000-8 500 m,whose rock is compact.By using the experimental data such as normal and casting thin sections observation,scanning electron microscopy,laser confocal microscopy,field emission electron microscopy,rate-controlled porosimetry,nuclear magnetic resonance,and centrifugation,this paper studies the petrological and pore structure characteristics of Bashijiqike sandstone reservoir.At the same time,the paper discusses the factors influencing the pore structure from the geological point of view of structure,sedimentation and diagenesis.The results show that the reservoir lithology is mainly feldspar lithic sandstone,and the composition maturity and structure maturity are moderate.The reservoir space is dominated by intergranular pores,followed by the intragranular dissolution and the intergranular dissolution,and then microfratures.Hence,the pore structure is complex and belongs to the fractured-pore type sandstone reservoir.According to the differences of the morphological characteristics of the nuclear magnetic resonance T_2 spectrum(T_e=0.2 ms)before and after centrifugation and the irreducible water saturation,the reservoir can be divided into three categories.The macropores dominate in the first category reservoir,taking up 35% of the samples mainly,in which irreducible water saturation is 25% after centrifugation;the macropores and micropores are fairly typical for the second category reservoir,taking up 20% of the samples,in which irreducible water saturation is 45% after centrifugation;the micropores dominatein the third category reservoir,taking up 45% of the samples,in which irreducible water saturation is 50%after centrifugation.Diagenesis is the main factor affecting the pore structure of reservoir and sedimentation is a prerequisite for pore structure and the microfracture produced by the later tectonic stress is an important factor forthe complex pore structure.
引文
[1]邱中建,赵文智,邓松涛.我国致密砂岩气和页岩气的发展前景和战略意义[J].中国工程科学,2012,14(6):4-8.
[2]Abu-Shanab M M,Hamada G M,Wally A A A.Improved porosity estimation in tight gas reservoirs from NMR and density logs[J].Emirates Journal for Engineering Research,2005,10(2):9-13.
[3]Sheng Ding,Tai Pham.Integrated approach for reducing uncertainty in the estimation of formation water saturation and free water level in tight gas resevoirs-case studies[C]//Anon.SCA International Symposium.TE-53/30/,2002.
[4]Wong P M.A novel technique for modeling fracture intensity:A case study from the pinedale anticline in Wyoming[J].AAPG Bulletin,2003,87(11):1717-1727.
[5]马志欣,朱亚军,杜鹏,等.鄂尔多斯盆地上古生界致密砂岩气藏储层成岩作用及成岩相:以苏里格气田桃X区块为例[J].湖北大学学报:自然科学版,2015,37(6):520-527.
[6]杨仁超,樊爱萍,韩作振,等.姬塬油田砂岩储层成岩作用及成岩演化[J].西北大学学报:自然科学版,2007,37(4):626-631.
[7]邓虎成,周文,周秋媚,等.新场气田须二气藏天然裂缝有效性定量表征方法及应用[J].岩石学报,2013,29(3):1087-1096.
[8]曾联波.低渗透砂岩油气储层裂缝及其渗流特征[J].地质科学,2004,39(1):11-17.
[9]张贵生.川西坳陷须家河组致密砂岩储层裂缝特征[J].天然气工业,2005,25(7):11-13.
[10]雷刚林,谢会文,张敬洲,等.库车坳陷克拉苏构造带构造特征及天然气勘探[J].石油与天然气地质,2007,28(6):816-821.
[11]孙家振,李兰斌,周新源,等.塔里木盆地库车凹陷克拉苏构造带典型构造样式与变形机理分析[J].石油实验地质,2003,25(3):247-251.
[12]王珂,张惠良,张荣虎,等.超深层致密砂岩储层构造裂缝特征及影响因素:以塔里木盆地克深2气田为例[J].石油学报,2016,37(6):715-728.
[13]王凯,王贵文,徐渤,等.克深2井区裂缝分类及构造裂缝期次研究[J].地球物理学进展,2015,30(3):1251-1256.
[14]王俊鹏,张荣虎,赵继龙,等.超深层致密砂岩储层裂缝定量评价及预测研究:以塔里木盆地克深气田为例[J].天然气地球科学,2014,25(11):1735-1745.
[15]王珂,戴俊生,商琳,等.曲率法在库车坳陷克深气田储层裂缝预测中的应用[J].西安石油大学学报:自然科学版,2014,34(1):34-40.
[16]雷刚林,戴俊生,马玉杰,等.库车坳陷克深三维区现今地应力场及储层裂缝数值模拟[J].大庆石油地质与开发,2015,29(1):18-24.
[17]王珂,戴俊生,刘海磊,等.塔里木盆地克深气田现今地应力场特征[J].中南大学学报:自然科学版,2015,46(3):941-952.
[18]史玲玲,唐雁刚,汪斌,等.库车坳陷克深5井区巴什基奇克组应力垂向分层特征[J].新疆石油地质,2016,37(4):430-436.
[19]王珂,张荣虎,戴俊生,等.库车坳陷克深2气田低渗透砂岩储层裂缝发育特征[J].油气地质与采收率,2016,23(1):53-60.
[20]王珂,张惠良,张荣虎,等.塔里木盆地克深2气田储层构造裂缝多方法综合评价[J].石油学报,2015,36(6):673-687.
[21]李爱芬,任晓霞,王桂娟,等.核磁共振研究致密砂岩孔隙结构的方法及应[J].中国石油大学学报:自然科学版,2015,39(6):92-98.
[22]王允诚,向阳,邓礼正,等.油层物理学[M].成都:四川科学技术出版社,2006.
[23]赖锦,王贵文,孟辰卿,等.致密砂岩气储层孔隙结构特征及其成因机理分析[J].地球物理学进展,2015,30(1):217-227.
[24]赖锦,王贵文,柴毓,等.致密砂岩储层孔隙结构成因机理分析及定量评价:以鄂尔多斯盆地姬塬地区长8油层组为例[J].地质学报,2014,88(11):119-2130.
[25]潘荣,朱筱敏,刘芬,等.克拉苏冲断带白垩系储层成岩作用及其对储层质量的影响[J].沉积学报,2014,32(5):973-980.
[2]Abu-Shanab M M,Hamada G M,Wally A A A.Improved porosity estimation in tight gas reservoirs from NMR and density logs[J].Emirates Journal for Engineering Research,2005,10(2):9-13.
[3]Sheng Ding,Tai Pham.Integrated approach for reducing uncertainty in the estimation of formation water saturation and free water level in tight gas resevoirs-case studies[C]//Anon.SCA International Symposium.TE-53/30/,2002.
[4]Wong P M.A novel technique for modeling fracture intensity:A case study from the pinedale anticline in Wyoming[J].AAPG Bulletin,2003,87(11):1717-1727.
[5]马志欣,朱亚军,杜鹏,等.鄂尔多斯盆地上古生界致密砂岩气藏储层成岩作用及成岩相:以苏里格气田桃X区块为例[J].湖北大学学报:自然科学版,2015,37(6):520-527.
[6]杨仁超,樊爱萍,韩作振,等.姬塬油田砂岩储层成岩作用及成岩演化[J].西北大学学报:自然科学版,2007,37(4):626-631.
[7]邓虎成,周文,周秋媚,等.新场气田须二气藏天然裂缝有效性定量表征方法及应用[J].岩石学报,2013,29(3):1087-1096.
[8]曾联波.低渗透砂岩油气储层裂缝及其渗流特征[J].地质科学,2004,39(1):11-17.
[9]张贵生.川西坳陷须家河组致密砂岩储层裂缝特征[J].天然气工业,2005,25(7):11-13.
[10]雷刚林,谢会文,张敬洲,等.库车坳陷克拉苏构造带构造特征及天然气勘探[J].石油与天然气地质,2007,28(6):816-821.
[11]孙家振,李兰斌,周新源,等.塔里木盆地库车凹陷克拉苏构造带典型构造样式与变形机理分析[J].石油实验地质,2003,25(3):247-251.
[12]王珂,张惠良,张荣虎,等.超深层致密砂岩储层构造裂缝特征及影响因素:以塔里木盆地克深2气田为例[J].石油学报,2016,37(6):715-728.
[13]王凯,王贵文,徐渤,等.克深2井区裂缝分类及构造裂缝期次研究[J].地球物理学进展,2015,30(3):1251-1256.
[14]王俊鹏,张荣虎,赵继龙,等.超深层致密砂岩储层裂缝定量评价及预测研究:以塔里木盆地克深气田为例[J].天然气地球科学,2014,25(11):1735-1745.
[15]王珂,戴俊生,商琳,等.曲率法在库车坳陷克深气田储层裂缝预测中的应用[J].西安石油大学学报:自然科学版,2014,34(1):34-40.
[16]雷刚林,戴俊生,马玉杰,等.库车坳陷克深三维区现今地应力场及储层裂缝数值模拟[J].大庆石油地质与开发,2015,29(1):18-24.
[17]王珂,戴俊生,刘海磊,等.塔里木盆地克深气田现今地应力场特征[J].中南大学学报:自然科学版,2015,46(3):941-952.
[18]史玲玲,唐雁刚,汪斌,等.库车坳陷克深5井区巴什基奇克组应力垂向分层特征[J].新疆石油地质,2016,37(4):430-436.
[19]王珂,张荣虎,戴俊生,等.库车坳陷克深2气田低渗透砂岩储层裂缝发育特征[J].油气地质与采收率,2016,23(1):53-60.
[20]王珂,张惠良,张荣虎,等.塔里木盆地克深2气田储层构造裂缝多方法综合评价[J].石油学报,2015,36(6):673-687.
[21]李爱芬,任晓霞,王桂娟,等.核磁共振研究致密砂岩孔隙结构的方法及应[J].中国石油大学学报:自然科学版,2015,39(6):92-98.
[22]王允诚,向阳,邓礼正,等.油层物理学[M].成都:四川科学技术出版社,2006.
[23]赖锦,王贵文,孟辰卿,等.致密砂岩气储层孔隙结构特征及其成因机理分析[J].地球物理学进展,2015,30(1):217-227.
[24]赖锦,王贵文,柴毓,等.致密砂岩储层孔隙结构成因机理分析及定量评价:以鄂尔多斯盆地姬塬地区长8油层组为例[J].地质学报,2014,88(11):119-2130.
[25]潘荣,朱筱敏,刘芬,等.克拉苏冲断带白垩系储层成岩作用及其对储层质量的影响[J].沉积学报,2014,32(5):973-980.