摘要
通过对YD油田延长组长4+5、长6砂岩储层薄片样品的系统研究,并结合样品的岩石学特征,详细分析了研究区所经历的成岩作用类型,建立了研究区延长组长4+5、长6砂岩的成岩演化序列,并划分了研究区的成岩阶段及孔隙演化。结果表明,研究区砂岩的成岩作用异常强烈且类型较多,其中对延长组砂岩储层原生孔隙大量消失起到关键作用的是压实、压溶和胶结作用,这些作用可使地下酸性流体失去流动能力,导致溶蚀作用发育较差,储层致密;根据碎屑岩成岩阶段划分规范,延长组砂岩目前已处于晚成岩初(A)期;砂岩孔隙的演化过程从原始孔隙的缩减演化到粒间孔的少量保留,最后演化为各类溶蚀孔发育,其中长4+5上储层更有利于油气的渗流与储集。
Based on the research of sandstone slice samples and its petrological characteristics in Chang 4 ＋ 5, Chang 6 sandstone reservoir of YD oilfield, diagenesis and the influence degree of diagenesis on porosity and permeability of reservoir were studied. Diagenetic evolution sequence in Chang 4＋ 5,Chang 6 sandstone reservoir was established and diagenetica stage, pore evolution of the study area were devided. The results indicated that sandstone diagenesis this area was strong and abundant. Mechanical compaction, pressure solution, cementation and metasomatism were the key factors which led to loss of the primary pores in Yanchang Group sandstone reservoir. Also, the above factorsresulted in flow ability lost of acidic ground fluids, which made dissolution become poor and reservoir become particularly tight. According to the classification discipline of clastics diagenesis phase, the sandstone of Yanchang Group experienced sorts of diagenesis, where its intensity was significant and was now in the early period of late diagenetic （A）. Sandstone pore had experienced many evolution processes, which were the initial pore slashed. A small amount of residual intergranular pores was retained and all kinds of pores gradually developed into corrosion pores. Diagenesis in upper Chang 4＋5 was more favorable for hydrocarbon transfusion and reservoir.
出处
《石油化工高等学校学报》
CAS
2015年第4期35-39,64,共6页
Journal of Petrochemical Universities
基金
国家自然科学基金项目(90210022)
关键词
YD油田
延长组
成岩作用
成岩演化序列
成岩阶段
孔隙演化
YD Oilfield
Yanchaug group
Diagenesis
Diagenetic evolution sequence
Diagenetic stage
Pore evolution
