摘要
利用岩心、铸体薄片、扫描电镜、高压压汞和恒速压汞等分析方法,研究方正断陷白垩系致密含砂砾岩储层储集空间类型、物性特征,对孔喉特征进行定量表征,探讨不同尺度孔喉分布规律及其对储层物性的控制作用。结果表明:方正断陷白垩系含砂砾岩储层主要发育残余粒间孔、粒间溶孔、粒内溶孔、晶间孔和微裂缝。孔喉半径分布区间为18 nm^10μm,孔喉半径基本小于1.0μm;孔隙半径分布在100~300μm之间,峰值分布在140~160μm之间,喉道半径集中在0.2~0.6μm之间。孔隙半径发育集中,喉道半径和孔喉比非均质性较强,随渗透率增大,喉道半径分布范围变宽,单峰值喉道半径变大,具有右偏的特征。含砂砾岩储层的大喉道对渗透率的控制作用明显,对孔隙度的影响较小。纳米级孔喉对渗透率贡献率影响较小,为1.07%~30.72%;对孔隙度贡献率影响较大,为47.71%~92.05%。孔喉结构分布特征对研究区致密储层物性有重要影响。
The characteristics of pore throat of tight reservoirs are significant for evaluating reservoir quality.Using core,cast thin section,scanning electron microscop(SEM),high pressure mercury penetration,rate-controlled mercury penetration,the reservoir types and physical properties of the Cretaceous tight glutenite reservoir in the Fangzheng Depression are studied,and the pore throat characteristics are quantitatively analyzed.The distribution of pore throats in different scales and theirs controlling action on reservoir physical properties were discussed.The results show that the residual intergranular pores,intergranular dissolved pores,intragranular dissolved pores,intercrystalline pores and microcracks are developed of the Cretaceous glutenite reservoirs in the Fangzheng Depression.The high pressure mercury penetration test showed that the pore throat radius distribution range was 18 nm^10μm,and the pore throat radius was almost less than 1.0μm.The rate-controlled mercury penetration test showed that the pore radius was distributed in the range of 100~300μm,the peak distribution was between 140~160μm,and the throat radius was concentrated at 0.2~0.6μm.Both test methods show that the pore radius is centrally developed,and the throat radius and the pore throat ratio are strong het-erogeneity.As the permeability increases,the distribution of the throat radius becomes wider,and the throat radius of the single peak becomes larger,which has a right biased feature.The large throat has an obvious effect on permeability in the glutenite reservoir,but the effect on the porosity is small.Nanoscale pore throat contributes less to permeability and has a greater impact on porosity.Statistics show that the contribution rate to permeability is 1.07%~30.72%,and the contribution rate to porosity is47.71%~92.05%.Therefore,nano-scale pore throat play an important role in contributing the tight reservoirs porosity of Fangzheng Depression.Consequently,the characteristics of pore throat structure distribution is very important for the physical properties of tight reservoirs.
作者
王有智
毛毳
刘丽莉
李丹
WANG Youzhi;MAO Cui;LIU Lili;LI Dan(Exploration and Development Research Institute of Daqing Oilfield Company Limited,Daqing,Heilongjiang 163712,China;School of Geosciences,Northeast Petroleum University,Daqing,Heilongjiang 163318,China;Jiamusi Customs of the People's Republic of China,Jiamusi,Heilongjiang 154002,China;School of Earth Science and Engineering,Hebei University of Engineering,Handan,Hebei 056038,China)
出处
《东北石油大学学报》
CAS
北大核心
2020年第2期36-45,112,I0003,I0004,共13页
Journal of Northeast Petroleum University
基金
国家科技重大专项(2016ZX05014-002)
国家自然科学青年基金项目(41702154)
河北省自然科学基金项目(D2017402165)。
关键词
储集空间
孔喉结构
孔喉参数
致密含砂砾岩
白垩系
方正断陷
storage space
pore throat structure
pore throat parameter
tight glutenite
Cretaceous
Fangzheng Depression
