《测井解释与数字处理》课程作业及思考题

《测井解释与数字处理》课程作业及思考题（2006级）第一章（绪论）思考题51-1．简述测井学或测井技术的基本特点。

中文“测井”一词，从字面上理解，应该是一个动词，反映了一种过程。

可以简单解释为用专门的仪器在井中进行地球物理测量的过程或技术体系。

在钻井井眼中，用特殊的测量装置连续记录井眼所穿过地层岩石的各种物理性质和相关信息，并提供这些记录和信息的直观显示。

在一定的物理实验、理论模型、刻度标定或经验统计的基础上，将这些记录转换成地质与工程参数，进而（帮助）解决一些地质与工程问题的一门应用性学科。

1-2．为什么说测井结果具有多解性？如何避免或降低测井资料解释应用的多解性？从应用的角度讲，测井记录的信息是一种间接的、物理信息。

由于测井记录的信息是地层岩石存在的响应，且受井眼环境、测量装置性能等因素影响，故将测井得到的物理信息转换为各种地质和工程参数或信息时就存在多解性。

谭廷栋教授认为多解性有三方面的原因：测量对象的复杂性、测量误差（仪器、环境等）、测量方法的不匹配。

可以通过综合分析多种测井信息进行最优化解释以降低测井资料解释应用的多解性。

1-3．概述测井资料在石油勘探开发中的主要应用。

测井是石油勘探开发过程Seismic->Drilling->Logging->Cementing->Perforating->Testing-> Monitoring中石油天然气勘探开发的重要技术环节。

也是获取地下岩石/层信息的手段（录井、钻井取心、测井）之一。

同时也是发现油气藏、评价油气藏的重要技术手段。

1-4．测井资料为什么需要解释？测井解释旨在解决以下问题：这些井中有多少油气？在什么位置？储层间是否连通？储层空间分布范围？如何产出？需要采取增产措施吗？储层评价是用测井资料划分井剖面的岩性和储集层，评价储集层的岩性（矿物成分和泥质含量）、储油物性（孔隙度和渗透率）、含油性（含油气饱和度和含水饱和度）、生产价值（预期产油、气、水）和生产情况（实际产油、气、水的情况及生产过程中储集层的变化）1-5．用英文表述well log, well logging, log interpretation.在英文里，‘well log’ or ‘well logging’都可以译成“测井”。

但是，A well log is a recording against depth of any of the characteristics of the rock formations traversed by a measuring apparatus in a well-bore. 显然，a well log or the well logs 指的是测井测量的结果，而非过程。

Well logging 则表示测井过程、测井方法或测井技术体系。

第二章（测井解释的基础）作业题与思考题32-1．熟记测井及测井解释涉及的基本术语的英文词汇。

地层温度T f，Formation Temperature孔隙度，Porosity地层压力，Formation Pressure渗透率，Permeability含水饱和度，Water Saturation电阻率，Resistivity溶液电阻率，Resistivity of Solutions井眼环境及术语•泥饼mud cake•井眼直径hole diameter, d h ;•泥浆电阻率drilling mud resistivity, R m;•泥浆滤液电阻率resis. of drilling mud filtrate, R mf;•侵入带invaded zone;•侵入带直径invasion diameter, d i;•冲洗带电阻率flushed zone resistivity, R xo;•原状地层电阻率uninvaded zone resistivity, R t;•冲洗带含水饱和度flushed zone water saturation, Sxo;•原状地层含水饱和度uninvaded zone water saturation, Sw侵入及电阻率剖面invasion and resistivity profile•阶梯状step;•过渡状transition•环带annulus水层侵入及电阻率剖面water-bearing zone油气层侵入及电阻率剖面hydrocarbon-bearing zone(非)均质(in-) homogeneity；非对称symmetry /asymmetry；各向同性/异性isotropy/anisotropy;动态侵入dynamic invasion油气藏，Reservoir岩性，Lithology/Mineralogy岩石固体组分的元素构成（8种主要元素占体积重量的99%）：Oxygen、Silicon 、Aluminum、Iron、Calcium、Sodium、Magnesium、Potassium等。

碎屑岩的结构及粒度Texture and Grain-Size of Clastic Rock碎屑岩的孔隙及孔隙结构Pore and Pore Structure等等专业术语，以上只是部分总结。

2-2．用英文表述下列概念：well log, well logging, log interpretation, porosity. permeability, saturation, resistivity, …A well log is a recording against depth of any of the characteristics of the rock formations traversed by a measuring apparatus in a well-bore.Well logging is mainly referring to the process, method or the system of techniques of logging. Log Interpretation is the explanation of logs b, GR, Resistivity, etc. in terms of well and reservoir parameters, zones, porosity, oil saturation, etc.Porosity is a measure of the void spaces in a material, and is a fraction of the volume of voids over the total volume, between 0–1, or as a percentage between 0–100%.Also,Porosity can be defined as the ratio of voids to the total volume of rock.Permeability in fluid mechanics and the earth sciences (commonly symbolized as κ, or k) is a measure of the ability of a porous material (often, a rock or unconsolidated material) to transmit fluids.Also,Permeability is the ability of a rock to transmit fluids.saturation is a relative measure of the amount of fluid that is dissolved or carried in a given medium.Water saturation is the amount of pore volume in a rock that is occupied by formation water.Electrical resistivity(also known as specific electrical resistance or volume resistivity) is a measure of how strongly a material opposes the flow of electric current.Also,Resistivity is the ability of a material to resist the flow of an electric current.2-3．熟练掌握地层水电阻率图版（矿化度、温度）使用方法。

Rw calculation from SP log 地层水电阻率图版是个三维（矿化度、温度、电阻率）的图版，知二求三。

第三章（常规测井方法要点回顾）作业题与思考题103-1．列表总结常规测井方法的测井曲线符号，测量结果的物理意义、单位及影响因素，探3-1．按照SP测井课堂总结模式（物理意义、符号、单位、成因/测量原理、主要应用），总结常规9种测井方法；3-2．在Excel中作出SP-1、SP-2图版；SP－1：先将摄氏温度转换为绝对温度，用式2－13计算；SP-2：稍复杂，需将式(2-11)—(2-22)综合应用。

SP-1图版SP-2图版未能作出。

3-3．在Excel中作出图8－15图版(GR相对值计算Vsh)，并讨论其适用条件；该图表明，如果储集岩石中含放射性物质较多，自然伽马相对值SHI偏高时，GCUR应该取较高的数值，使计算的Vsh比SHI较低；反之，GCUR取较低的数值。

另外，得正确理解GRmax和GRmin的含义，此处省略。

本方法适用于只有泥质含放射性物质的岩石，如果非泥质成分含有放射性矿物，将使计算结果明显偏高。

取多种测井方法计算的最小值可以作为最优化结果。

3-4．在Excel中作出图10-3图版(中子测井挖掘效应)；注意公式（10－22）中个参数的单位3-5．阅读有关文献，综述时间平均公式的来源、应用条件等。

威利公式来源：Expressions that relate velocity to porosity and to pore-fluid compressibility are among the most important deliverables of rock physics. Such relations are used often as additional controls for inferring porosity from well logs, as well as in-situ indicators of pore fluid type. The oldest and most popular is the Wyllie et al. (1956) equation:F S P τττ+= （1）where P τ is the measured traveltime of a P -wave, s τ is the traveltime expected in the solid-phase material, and F τ is the traveltime expected in the pore fluid. It follows from equation (1) thatpFpS p V V V φφ+-=11 （2） where φ is porosity, p V is the measured P -wave velocity, and pS V and pF V are the P -wave velocities in the solid and in the pore-fluid phases, respectively. 威利公式应用条件：Formulas (1) and (2) present a simple and convenient, but deceptive form of summarizing extensive experimental data. Indeed, there is no physical reason for the total traveltime of a wave in a two-component composite to be thesumof the traveltimes in the individual components (unless the two componentsare arranged in layers normal to the direction of propagation, and the wavelength is small as compared to the thickness of an individual layer.Raymer 公式应用条件：The Raymer et al. (1980) equation, which is an improved version of the Wyllie et al. (1956) time-average equation, can be reliably used to relate P -wave velocity to porosity in cementedsaturated (fast) sandstones in a wide porosity range. These empirical equations areinadequate if applied to highporosity unconsolidated uncemented (slow) rocks, such as those present in the North Sea and Gulf of Mexico. Rigorous effective medium relations between porosity and velocity are indispensable when the goal is to diagnose the rock, i.e., to derive its internal grain-scale structure from velocity and porosity data. 3-6．声速测井压实校正的原因、方法(p.57-59)； 由威利公式可得纯岩石孔隙度：maf mat t t t ∆-∆∆-∆=φ但是各地用此式计算孔隙度的结果，发现比实测岩心的孔隙度偏高。