摘要
计算机层析 (CT)是对物体内部横断面进行成像的一种无损检测技术 ,在石油工业中已发展成为一门特殊的定量测试技术。利用CT确定岩心的基本物理参数 (体积密度、孔隙度、饱和度 )具有常规方法无法相比的优越性。用CT确定密度的方法有单能扫描法、双能扫描法、线性插值法 ;确定孔隙度的方法有单次扫描法、两次扫描法、测井解释法、图像分析法 ;确定饱和度的方法有单能两次扫描确定含水率、双能扫描确定含水率、单能扫描确定两相流体饱和度、单能扫描确定三相流体饱和度、双能扫描确定三相流体饱和度、图像分析法确定流体饱和度。利用ACTIS高分辨率工业CT对岩心进行了扫描 ,试验表明利用CT计算的结果与常规方法的测定值符合较好。CT法测得的平均密度与煤油法测定值相比 ,平均绝对误差不到 1 .2 %。饱和煤油法与氦孔隙计法测量孔隙度之间的平均误差为8.5% ,CT两次扫描法与饱和煤油法之间的误差为7.8% ,说明利用CT测量岩心的孔隙度是成功的。利用ACTIS工业CT对油水非稳态相对渗透率驱替试验进行扫描 ,计算驱替过程中饱和度的变化与重量法的计算值一致。图 5表 1参 7(李玉彬摘 )
Computed tomography (CT) is a non destructive technique that generates an image of cross sectional slice of an object. In petrophysical field it has become a quantitative analytic method. Using CT to determine the basic petrophysical properties of cores (buck density, porosity, fluid saturation) is more advantage than conventional core testing methods. This paper discusses single energy scan method, dual energy scan method and linear interpolation method for density; single scan method, dual scan method, well log interpreting method and image analysis method for porosity; single energy scan method, dual energy scan method for water cut; single energy scan for two phase fluids saturation; single energy scan and dual energy scan for three phase fluids saturation and image analysis method for saturation. By scanning the core with ACTIS high resolution industrial CT, we indicate that the results by CT is similar as conventional method. Comparing mean density measured by CT with kerosene mass method, mean error is less 1.2%. Mean error of porosity by kerosene mass method and helium porosimetry method is 8.5%, and the same by CT dual scan method and kerosene mass method is 7.8%.This shows that measuring porosity of core by CT is successful.Scanning the non steady state relative permeabilities experiment,the variation of saturation in flooding process is well agreed with the result of mass method.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
1999年第6期86-90,共5页
Petroleum Exploration and Development
关键词
油气层物理
CT
岩心分析
物理参数
Computed tomography, Scanning, Density, Porosity, Saturation
