核磁共振测井在低孔低渗储层渗透率计算中的应用

针对南海东部HZ地区低孔低渗储层普遍存在的孔渗之间相关性差、用常规方法计算渗透率精度低的问题,分析了研究区低孔低渗储层孔隙结构,研究了储层综合物性参数与岩石孔隙结构参数之间的关系,利用核磁共振测井弛豫时间分布对岩石孔隙结构的表征能力、由研究区储层岩心的核磁实验测量数据、建立了适合本地区计算低孔低渗储层渗透率的关系式,并用实例对该方法的可靠性进行了验证。

An application of NMR logging to calculating permeability in low porosity and low permeability reservoir

For the low porosity and permeability reservoir in HZ area,the eastern South China Sea,there is a poor corrclation between porosity and permeability,and it is not accurate to calculate permeability by conventional methods.Therefore,the pore structure is analyzed,and the correlation between integrated petrophysical paramctcrs and rock pore structure parameters is studicd for the low porosity and permeability reservoir.By using the ability for NMR T2 distribution to characterizc microscopic pore structure of rocks,a quantitative relationship to calculate permeability of the tight reservoir rocks has been established on a basis of measured NMR data of core samples form these rescrvoir rocks in laboratory.Finally,the reliability is verified for this relationship by some examples.