【目的】车排子凸起中生界稠油资源丰富,但原油生物降解严重,制约了勘探进程。【方法】为明确车排子凸起东翼中生界原油的生物降解程度,对车排子凸起东翼侏罗纪和白垩纪储层样品抽提出的饱和烃和芳香烃进行了气相色谱—质谱(GC-MS)分析...【目的】车排子凸起中生界稠油资源丰富,但原油生物降解严重,制约了勘探进程。【方法】为明确车排子凸起东翼中生界原油的生物降解程度,对车排子凸起东翼侏罗纪和白垩纪储层样品抽提出的饱和烃和芳香烃进行了气相色谱—质谱(GC-MS)分析,采用分子地球化学指标,对其进行定性与定量评价。【结果】通过聚类分析,将原油分为Ⅰ、Ⅱ、Ⅲ、Ⅳ四类族群。PM(Peters and Moldowan)法分析结果表明Ⅰ_(1)类和Ⅱ_(1)类原油的生物降解程度达PM7,Ⅰ_(2)类和Ⅳ类原油的生物降解程度为PM8;Ⅱ_(2)类和Ⅲ_(1)类原油的生物降解程度为PM9,Ⅲ_(2)类原油生物降解程度为PM9+。基于优化的Manco法求得的MN_(1)值介于19693~215623,Ⅰ类原油的MN_(2)值介于769~919,Ⅱ类原油的MN_(2)值介于768~907,Ⅲ类原油的MN_(2)值介于906~954,Ⅳ类原油的MN_(2)值介于774~817。同一原油族群的Manco数与原油密度、黏度、非烃和沥青质含量均呈现良好的正相关性,与总烃呈现良好的负相关性。优化的Manco法成功厘定了生物降解程度在PM7-PM9+的储层样品,与PM等级评价具有一致性。【结论】与PM法相比,优化的Manco法对原油生物降解的识别分辨率更高。通过PM法定性评价和优化Manco法定量评价相结合,可以很好地揭示原油物性的变化,对稠油区的油气勘探有重要的指导作用。展开更多
准噶尔盆地车排子凸起新近系沙湾组一段1砂组(N1 s 11)勘探程度整体较高,挖潜难度越来越大,急需转变研究思路,为后续油藏再认识和寻找新的勘探目标提供支撑。综合利用岩心、薄片、测井和地震等资料,对砂体内部钙质隔层识别标准、成因机...准噶尔盆地车排子凸起新近系沙湾组一段1砂组(N1 s 11)勘探程度整体较高,挖潜难度越来越大,急需转变研究思路,为后续油藏再认识和寻找新的勘探目标提供支撑。综合利用岩心、薄片、测井和地震等资料,对砂体内部钙质隔层识别标准、成因机制和盖层性能进行了研究,剖析了钙质隔层的油气地质意义。结果表明,钙质隔层位于1砂组砂体中上部,岩性主要为钙质胶结细砂岩,测井曲线上具有高Rt、低AC、高DEN、GR值变小、SP具有一定回返幅度的特征。钙质隔层具有“三元复合”成因,“短期旋回进积—退积作用转换面、干旱环境下的浅水辫状河三角洲沉积体系、沉积期—浅埋藏期强烈钙质胶结”三要素控制了钙质隔层的形成。根据盖层突破压力分析,钙质隔层可以作为有效盖层。以上述认识为指导,开展了基于隔层分布的油藏特征再认识,在储量区周缘新发现多个有利勘探区块,指导了多口井的成功钻探,发现了规模储量,取得了较好的勘探效果。展开更多
Deep-seated cracked gas exploration was achieved great breakthrough in Es4L of the Minfeng area on the northern slope of the Dongying Sag. Carbon isotopic and molecular compositions studies revealed the characteristic...Deep-seated cracked gas exploration was achieved great breakthrough in Es4L of the Minfeng area on the northern slope of the Dongying Sag. Carbon isotopic and molecular compositions studies revealed the characteristics of wet gas and a normal trend of carbon isotopic composition. Empirical cutoff points of δ13C2 and δ13C3 and light hydrocarbon compositions distinguished the cracking gas as sapropelic gas. Variations in i/nC5, i/nC4 and δ13C2 fur-ther confirmed that the gas was cracked from residual kerogen. Source characteristics indicated that the gas was de-rived from mature-highly mature source rocks of Es4 with kerogen type II being dominant mixed with some oil-cracking gas. Burial history modeling indicated that there were two hydrocarbon charging periods in Es4L reser-voirs. The first period refers to the Guantao-Minghuazhen stage dominated by oil charging, while the second period refers to the Minghuazhen stage and has been dominated by cracked gas charging till now.展开更多
文摘【目的】车排子凸起中生界稠油资源丰富,但原油生物降解严重,制约了勘探进程。【方法】为明确车排子凸起东翼中生界原油的生物降解程度,对车排子凸起东翼侏罗纪和白垩纪储层样品抽提出的饱和烃和芳香烃进行了气相色谱—质谱(GC-MS)分析,采用分子地球化学指标,对其进行定性与定量评价。【结果】通过聚类分析,将原油分为Ⅰ、Ⅱ、Ⅲ、Ⅳ四类族群。PM(Peters and Moldowan)法分析结果表明Ⅰ_(1)类和Ⅱ_(1)类原油的生物降解程度达PM7,Ⅰ_(2)类和Ⅳ类原油的生物降解程度为PM8;Ⅱ_(2)类和Ⅲ_(1)类原油的生物降解程度为PM9,Ⅲ_(2)类原油生物降解程度为PM9+。基于优化的Manco法求得的MN_(1)值介于19693~215623,Ⅰ类原油的MN_(2)值介于769~919,Ⅱ类原油的MN_(2)值介于768~907,Ⅲ类原油的MN_(2)值介于906~954,Ⅳ类原油的MN_(2)值介于774~817。同一原油族群的Manco数与原油密度、黏度、非烃和沥青质含量均呈现良好的正相关性,与总烃呈现良好的负相关性。优化的Manco法成功厘定了生物降解程度在PM7-PM9+的储层样品,与PM等级评价具有一致性。【结论】与PM法相比,优化的Manco法对原油生物降解的识别分辨率更高。通过PM法定性评价和优化Manco法定量评价相结合,可以很好地揭示原油物性的变化,对稠油区的油气勘探有重要的指导作用。
文摘准噶尔盆地车排子凸起新近系沙湾组一段1砂组(N1 s 11)勘探程度整体较高,挖潜难度越来越大,急需转变研究思路,为后续油藏再认识和寻找新的勘探目标提供支撑。综合利用岩心、薄片、测井和地震等资料,对砂体内部钙质隔层识别标准、成因机制和盖层性能进行了研究,剖析了钙质隔层的油气地质意义。结果表明,钙质隔层位于1砂组砂体中上部,岩性主要为钙质胶结细砂岩,测井曲线上具有高Rt、低AC、高DEN、GR值变小、SP具有一定回返幅度的特征。钙质隔层具有“三元复合”成因,“短期旋回进积—退积作用转换面、干旱环境下的浅水辫状河三角洲沉积体系、沉积期—浅埋藏期强烈钙质胶结”三要素控制了钙质隔层的形成。根据盖层突破压力分析,钙质隔层可以作为有效盖层。以上述认识为指导,开展了基于隔层分布的油藏特征再认识,在储量区周缘新发现多个有利勘探区块,指导了多口井的成功钻探,发现了规模储量,取得了较好的勘探效果。
基金supported by the Primitive Research Fund for Excellent Young and Middle-aged Scientists of Shandong Province (Grant No.BS2010HZ016)the University Research Program of Shandong Province (Grant No. J09LE08)the Open Fund of Key Laboratory of Depositional Mineralization and Sedimentary Minerals, Shandong Province (Grant No. DMSM200807)
文摘Deep-seated cracked gas exploration was achieved great breakthrough in Es4L of the Minfeng area on the northern slope of the Dongying Sag. Carbon isotopic and molecular compositions studies revealed the characteristics of wet gas and a normal trend of carbon isotopic composition. Empirical cutoff points of δ13C2 and δ13C3 and light hydrocarbon compositions distinguished the cracking gas as sapropelic gas. Variations in i/nC5, i/nC4 and δ13C2 fur-ther confirmed that the gas was cracked from residual kerogen. Source characteristics indicated that the gas was de-rived from mature-highly mature source rocks of Es4 with kerogen type II being dominant mixed with some oil-cracking gas. Burial history modeling indicated that there were two hydrocarbon charging periods in Es4L reser-voirs. The first period refers to the Guantao-Minghuazhen stage dominated by oil charging, while the second period refers to the Minghuazhen stage and has been dominated by cracked gas charging till now.
