【作者】 江玉龙；

【导师】 王祝文；

【作者基本信息】 吉林大学 ， 固体地球物理学， 2009， 博士

【摘要】 针对引进的多台Halliburton公司的P型核磁共振成像测井仪,剖析了其特殊的采集模式和数据记录格式,完成了时间域和深度域的P型核磁处理技术研究,提出了一种改善核磁测井油气识别的方法,自行研制了一套符合区域地质条件的核磁测井精细解释处理软件。软件的时间域处理效果与国外公司的解释处理结果完全一致,在参数选取和处理速度等方面更加灵活和方便快捷。从第一类积分方程的反演求解入手,讨论了核磁解谱方法,推导出适合于岩石核磁弛豫多指数反演的三种方法(改进的奇异值分解法和模平滑法及联合迭代反演SIRT法),对这些算法的具体实现过程进行了详细的论述,从理论和实例处理两方面讨论分析了三种算法优缺点。讨论了解的分辨率,并给出了最优反演模型的选取原则,奇异值分解算法适合于信噪比较高的核磁弛豫数据反演,模平滑算法灵活性较大,适应于较低信噪比的核磁弛豫数据反演。在解谱的基础上,对P型核磁的T2谱拼接与平滑进行了深入的研究,利用硬拼接和三次样条插值法,对T2谱进行处理,与国外软件的处理结果相比较,取得了良好的效果。总结了前人对于岩石孔隙中内流体极化扩散弛豫规律的研究成果,分析了岩石孔隙中内梯度场下油水弛豫规律,在广泛调研国内外核磁共振流体识别方法的基础上,利用T1 T2搜索来识别流体的研究思路,在时间域内搜索计算T1 T2的值,然后进行油气分析,计算各种流体的孔隙度,油气识别技术从定性识别到定量计算变为可能。更多还原

【Abstract】 It has cost much for China to import some MRIL-P made by Hallliburton, the processing software of which is the processing and analyzing systems based on the geological situation of oil and gas aboard. Therefore there exist some analyzing and processing methods in the systems which are not suitable for the situation of China. On the other hand, the high cost of the imported software and its cost in the processing and interpretation will also increase that of NMR logging. So it is not advisable to spread this kind of logging method in China.The thesis deals with the following points:First, DPP and PETROSITE by Hallliburton are seriously anatomized. By analyzing its manners of NMR logging, it makes clear of the .cls format to form the foundation of the later data processing.It studies on the signal preprocessing method in NMR logging.The records in NMR logging are a couple of channels of spin echoes that need a filtering processing and an estimate of the signal phase, so an echo signal curve including the spin echo scope as well as noise, which is used to process the T2 spectrum inversion and so on, and a noise curve only including noise, which is used to analyze the logging quality, can be obtained. Phase correcting, smoothness stacking and filtering processing on NMR logging data is necessary when a signal curve is ensured.MRIL-P makes time but not actual logging depth as its index to record the NMR logging signals, so it is necessary to convert the time index to the actual logging depth.The NMR curve processed previously is a porosity decay line which can not reflect the porosity situation directly. So it is necessary to invert the decay line into several T2 relaxation time as well as the sizes of the corresponding porosity, that is, to invert into the T2 distribution.Second, it analyzes particularly the T2 inversion by the means combining mathematics and physics, and induces three kinds of methods: norm smoothing method and SVD method. It makes a contrastive analysis on the merits and demerits between them theoretically and experimentally. The norm smoothing method is stable and is easy to realize the non-negativity confine, also the result has a reasonable continuity and a high resolution .This method is suitable for the data inversion when SNR is above 20. SVD is fast speed and is reasonable when SNR is above 80. But it can result in the abnormality of T2 spectrum owing to the constraint of non-negativity confine although it suppresses noise excessively. Considering their differences responding to SNR, and taking into account of the relationship among the SVD coordination factorλ, norm smoothing factorαand SNR, the thesis argues that establishing the corresponding method of correction can improve the quality of the inverted results.Third, the thesis studies how to confirm the reservoir parameter of NMR porosity on the basis of T2 spectrum inversion. It studies to establish the models of NMR porosity and permeability explanation, and to ascertain the reservoir parameters such as NMR total porosity, NMR effective porosity, clay bound fluid porosity, capillary bound fluid porosity, bound fluid saturation, permeability and so on.Taking the logging research in Liaohe region for example, the thesis makes a close study on the NMR features of the reservoir rocks, establishes the NMR analysis parameters ,analysis standard and analysis models fit for the conditions of the reservoir in Liaohe and analyzes the NMR logging data by the self-developed software ,therefore to search some new favorable zones.It studies the relationship between the NMR relexation stamp and rock petrophysics property systematically, to clarify the similarities and differences between the logging results of NMR and analysis results of conventional core. It selects kinds of the rock of oil-gas reservoir to research on many aspects such as reservoir fluid NMR properties, NMR T2 response, pore size distribution, porosity, permeability, moveable fluid and T2 cutoff time and the impact of paramagnetic ion on NMR logging and so on.The reservoir water salinity and formation temperature have small influence on NMR signal. The signal intensity and value in the condition of high mineralization of water is a little smaller than that of the purified water. So the reservoir water salinity and formation temperature have small impact on the NMR logging results.As the NMR spectrum of sandstone core sample is similar to throat radius distribution, it can be converted to pore distribution or capillary pressure- saturation curve. The reduction eoefficient differs in terms of places, and it is often well night the same when in the same core sample reservoir of the same oil field.The thesis sums up the former researching findings for the internal flow in the rock pore and analyzes the oil and water relaxation law of G in rock pores. Based on a wide research on how to identify NMR fluid at home and abroad, identifying fluid is conducted by means of T1T2.,and then is converted into T2 spectrum to reduce the influence of noise. So the effect of the different T2 is perfect.Finally ,Based on the above research, MRIL-P software in a microcomputer version is developed on the platform of LEAD. When this software is applied to process and analyze the logging data, it leads to a better result compared to that through the DPP.更多还原