石油与天然气地质 ›› 2006, Vol. 27 ›› Issue (2): 194-199,217.doi: 10.11743/ogg20060209

• 成藏(矿)作用 • 上一篇    下一篇

用储层油气包裹体岩相学确定油气成藏期次—以鄂尔多斯盆地陇东油田为例

李荣西1, 席胜利2, 邸领军2   

  1. 1. 长安大学, 陕西, 西安, 710054;
    2. 中国石油, 长庆油田分公司, 陕西, 西安, 710021
  • 收稿日期:2006-01-10 出版日期:2006-04-25 发布日期:2012-01-16
  • 基金资助:

    国家重点基础研究发展规划(973)项目(G2003CB214600)

Oil/gas reservoiring phases determined through petrographic analysis of hydrocarbon inclusions in reservoirs taking Longdong oilfield,Ordos basin,as an example

Li Rongxi1, Xi Shengli2, Di Lingjun2   

  1. 1. Chang'an University, Xi'an, Shaanxi, 710054;
    2. Changqing Oilfield Company, PetroChina, Xi'an, Shaanxi, 710021
  • Received:2006-01-10 Online:2006-04-25 Published:2012-01-16

摘要:

鄂尔多斯盆地陇东油田长3油层砂岩储层主要成岩作用有压实作用、胶结作用、溶蚀作用和裂隙作用等,成岩自生矿物以绿泥石、自生石英、方解石和石膏为主。根据油气包裹体寄主成岩矿物的形成时间序列,识别出两期油气包裹体。第一期油气包裹体形成于早成岩阶段晚期埋藏成岩过程中,分布在石英和长石等矿物溶蚀孔隙、次生加大边底部和早期裂隙中,包裹体形态不规则,一般较小(多为3~8μm),为多相烃类包裹体。第二期油气包裹体形成于晚成岩阶段晚期盆地抬升阶段,分布在晚成岩阶段的晚期裂隙、硅质胶结物和亮晶方解石胶结物中,油气包裹体普遍含盐水,油、气、水相态边界清楚。研究认为,第一期油气包裹体代表了油气运移充注过程,而第二期油气包裹体代表了油气大规模聚集成藏过程。应用不同期次油气包裹体形成温度与储层沉积热演化史地质分析方法,确定本区油气充注运移时间约为122 Ma(早白垩世),而油气大规模聚集成藏时间约为80 Ma(晚白垩世晚期)。

关键词: 油气包裹体, 岩相学, 成藏时间, 陇东油田, 鄂尔多斯盆地

Abstract:

The main diagenetic types of the sandstone reservoirs in Chang-3 reservoir in Longdong oilfield,Ordos basin,include compaction,cementation,corrosion and fracturing.The diagenetic authigenic minerals are dominated by chlorite,authigenetic quartz,calcite and gypsum.Two different phases of hydrocarbon inclusions have been identified according to the formation time series of the host diagenetic minerals.The hydrocarbon inclusions formed in the first phase would have been formed during the burial diagenesis in late early diagenetic stage,and are distributed in the dissolution pores and bottom of overgrowth edge of minerals,such as quartz and feldspar,as well as in earlier fractures.They are characterized by irregularity in shape and small in size,gene-(rally) in the range of 3-8 μm,and are dominated by multiple phase hydrocarbon inclusions.The hydrocarbon inclusions formed in the second phase would have been formed during basin uplifting stage in late latediagenetic stage,and are distributed in the late-formed fractures,siliceous cement and sparry calcite cement.They gene-(rally) contain saline water,and the boundaries of oil,gas and water are clear.It is believed that the former represents the process of hydrocarbon migration and charging,while the latter represents the process of large scale oil/gas accumulation and reservoiring.Based on the temperatures of hydrocarbon inclusion formed in various phases and analyses of the sedimentary and thermal evolution history of reservoirs,the time of hydrocarbon migration and charging is determined to be about 122 Ma(Early Cretaceous),while that of large-scale accumulation and reservoiring is about 80 Ma(late Late Cretaceous).

Key words: hydrocarbon inclusion, petrography, time of reservoiring, Longdong oilfield, Ordos basin

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