摘要
讨论了电缆NMR测井仪、随钻NMR测井仪以及井下NMR流体分析仪的测量原理与主要功能。从理论和实用两个角度分析了NMR为什么迄今未能成为核心测井方法,以及能否成为核心方法和NMR测井的未来发展方向。认为NMR测井成为核心方法的途径是开发价格较低、测速较快、专门针对地层孔隙度和渗透率的NMR测井仪,使之在测速、精度、纵向分辨率以及价格等方面达到可以与常规测井相当的程度,从而结合到常规测井系列中去,或取代常规测井的孔隙度测量功能;开发识别地层流体和准确测量饱和度的NMR测井仪,作为特殊方法使用,不要求它有常规测井的速度,但要求有更大的探测深度和更高的流体分辨能力。同时,充分发挥其定位观测的特点,提供地层径向方位的多个饱和度测量,从而得到冲洗带、侵入带和原状地层的流体饱和度剖面;综合应用NMR测井观测到的T1、T2、HI以及D信息,发展更加普遍适用的NMR孔隙度、渗透率以及流体饱和度的测井模式和解释处理方法。
NMR has been widely used in oilwell logging and formation evaluation. There are a lot of improvements since 1998, including NUMAR/Halliburton's multi-frequency MRIL-Prime tool, Schlum-berger's CMR-Plus, Halliburton's NMR logging-while-drilling tool and NMR downhole fluid analyzer integrated with formation tester RDT. This paper summarizes the latest advancement in NMR logging tool development in details. Then from theoretical and practical view explained is why NMR is still not the key device in today's logging tools family although it provides powerful information for formation evaluation. It is pointed out that as a porosity tool, NMR provides the most accurate measurement with very few effects, but it's limited by its logging speed, vertical resolution, and service price. As bound fluid and permeability tool, NMR models are empirical and formation dependent. As saturation tool, current NMR has too shallow depth of investigation for gas and light oil detection. The ways for NMR to become conventional and key device are that develop low cost, fast logging speed and higher vertical resolution tool for NMR porosity and permeability measurement; develop a special NMR saturation tool for oil and gas detecting to take full advantage of the NMR positioning and slice measurement, and T1、T2、HI and D three dimensions information.
出处
《测井技术》
CAS
CSCD
2003年第4期265-269,共5页
Well Logging Technology
