岩石物理学及其应用Rock--Physics.ppt

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,Rock physics and its applications,岩石物理学及其应用,贺振华 曹均,成都理工大学 信息工程学院,2010,年,9,月,提纲,Outline,以王之敬（,Wang Zee,）的学术报告为主，适当增补、修改了一些内容。,What is rock physics?,什么是岩石物理,Why rock physics?,为什么要研究岩石物理,Uses and abuses,应用及滥用,Some recent results,一些近期结果,Challenges,挑战,主要参考文献,1,）陈颙，黄庭芳著，岩石物理学，北京大学出版社，,2001,年,2,）陈颙，黄庭芳，刘恩儒 编著，岩石物理学，中国科学技术大学出版社，,2009,3,）,王之敬（,Wang Zee,）,“,岩石物理概述,”,学术报告（,PPT,），,2002,4,）贺振华、黄德济、文晓涛著 裂缝油气藏地球物理预测，四川科学技术出版社，,2007,年,5,）,R.E.Sheriff et.al.,Reservoir Geophysics,SEG,1992,6,）,Amos,Nur,著，许云译，双相介质中波的传播，石油工业出版社，,1986,7)Per,Avseth,Tapan,Mukerji,and Gary,Mavko,Quantitative Seismic Interpretation,Applying Rock Physics Tools to Reduce Interpretation Rick,Cambridge University Press,2005,8,）,Leon Thomsen,，,Understanding seismic anisotropy in exploration and exploitation,，,SEG,，,2002,9,）,G.Mavko,T.Mukerji,J.Dvorkin,The rock physics handbook,tools for seismic in porous media,Cambridge University Press,2003,10,）,B.,.,ussell,.,edlin,Fluid-property discrimination with AVO:A,Biot-Gassman,prospective.2003 Geophysics,68(1):2939,主要参考文献（续）,11,）,B.Gurevich,and,J.Galvin,Fluid substitution,dispersion,and attenuation in fractured and porous reservoirsinsights from new rock physics,modles,2007,The Leading EDGE,26(9),11621168,12,）邹文，基于地震资料的流体识别技术研究，成都理工大学 博士论文,2008,13,）王炳章 地震岩石物理学及其应用研究，成都理工大学 博士论文,2008,14,）赵群 面向起伏地表和缝洞储层的物理模拟技术研究，成都理工大学 博士论文,2008,15,）马中高 碎屑岩地震岩石物理学特征研究，成都理工大学 博士论文,2008,16,）刘雯林 油气田开发地震技术，石油工业出版社,1996,1,、岩石物理学概述,王之敬（,Wang Zee,）为成都理工大学校友，现为美国,Chevron Texaco,公司的研究员，美国斯坦福大学客座教授。杰出的国际岩石物理学家，曾任美国,SEG,协会副主席。,Laboratory measurements,ChevronTexaco,Rock,Physics,Laboratories,1,、岩石物理学概述,Rock physics,Studies the physics of rocks but mostly concentrates on,seismic properties,(velocity,impedance,attenuation)of,sedimentary,rocks in relation to other petrophysical properties and reservoir parameters,顾名思义，岩石物理研究岩石的物理性质，但主要集中在沉积岩石的地震特性,:,波速、阻抗、衰减，以及与其他岩性和油藏参数的关系,What does rock physics do?,Bridges,rock and fluid properties and seismic data,连接地震数据和岩石、流体特性的桥梁,Is the,physical basis,for seismic reservoir characterization and direct hydrocarbon detection,地震油藏定性描述及直接找油气的物理基础,地球物理,地质岩性,石油工程,岩石物理,三个学科的桥梁,Reservoir properties,Porosity,孔隙度,Density,密度,Saturation,饱和度,Fluid type,流体类型,Pressure,压力,Temperature,温度,Fracture,裂隙,Seismic properties,Seismic velocity,地震波速,Travel time,走时,Impedance,阻抗,Amplitude,振幅,AVO response,AVO,响应,Other attributes,其他属性,Rock Physics:,bridge,between reservoir,and seismic properties,4D Feasibility&Seismic modeling,四维地震可行性及地震模拟,Interpretation and Inversion,解释及反演,Rock Physics,Rock Physics,Role of Rock Physics in,Seismic Lithology,Lithology,porosity,fluids,岩性、孔隙度、流体类型,Seismic properties and reflectivity are controlled by lithology,fluids,porosity,pressure,temperature,mineralogy,texture,etc.,地震性质及反射率受控于岩性、流体类型、孔隙度、压力、温度、矿物、层理、等,What are the relationships between rock/fluid and seismic properties?,地震性质与岩性、流体类型之间的关系是什么,Do the predicted or inverted properties make physical sense?,预测或反演来的特性是否有物理意义,Rock physics is the basis for building the predictive tools and interpreting the predicted or inverted data,岩石物理是建立预测工具及解释反演结果的物理基础,Rock Physics,Rock Physics,Seismic data,Rock properties,Seismic attributes,地震属性,Current emphasis is on statistical correlations without worrying about physical meaning,目前着重于统计相关，而不顾及其物理意义,But seismic attributes are influenced by physical and geological properties of rocks and fluids,但岩石、流体的物理及地质特性影响地震属性,Rock physics helps us understand the relationships among attributes,岩石物理帮我们理解各种属性间的关系,Role of Rock Physics in,Seismic Attributes,Rock Physics,Rock Physics,Seismic data,Rock properties,Rock Physics in,Reservoir Characterization,4D feasibility,四维地震的可行性,Effects of fluid,pressure,and temperature changes caused by production/injection on seismic velocities/impedances and reflectivity,由采油、注流体引起的流体、压力、温度的变化对地震波速、阻抗、反射率的影响,Are the changes large enough to be resolved seismically?,这些变化是否大于地震的分辨率,Quantitative Interpretation,定量解释,Time-lapse seismic data measures the overall changes caused by several factors,时移地震数据测到的变化是由几个因素引起的,Rock physics quantifies/decomposes these factors,岩石物理对这些因素分解、量化,Rock Physics,Rock Physics,Seismic data,Rock properties,Rock Physics in,Angle Dependent Reflectivity,Angle-dependent reflectivity,依赖于角度的反射率,Seismic reflectivity at non-zero angles is controlled by more than the P-wave impedance contrast,非零度入射的地震反射率并非只受纵波阻抗差的控制,How are seismic properties affected by rock properties?,地震特性如何受到岩石特性的影响,How do variations in rock properties affect angle-dependent reflectivity?,岩石特性的变化如何影响依赖于角度的反射率,Interpretation,解释,Seismic data measures the overall effects of many factors,地震测到的是各种影响的总和,Rock physics quantifies/decomposes these factors,岩石物理对这些因素分解、定量化,Rock Physics,Rock Physics,Seismic data,Rock properties,Rock physics:uses and abuses,岩石物理的应用与滥用,Theories and models,理论与模型,Laboratory measurements and empirical relations,实验室测量与经验关系,Rock physics:uses and abuses,Theories and models,理论与模型,Fast,inexpensive,and sometimes simple,快速、节省、有时简单,But,但是,Still require measurement of input parameters,仍需去测量输入参数,All theories need assumptions to simplify math,and some of which may be physically unrealistic,所有的理论都需要假设以简化数学，这些假设有时在物理上不现实,Its imperative to know the range of applicability of a theory or model,对于一个理论，一定要弄懂它的应用区间,Beware fudge factors,主要其中的可调（虚假）参数,Example:time-average equation for fluid substitution,例如：,用时间平均公式来做流体替换,All models are wrong some are useful,所有模型都有问题,但有些是有用的。,（,Per,Avseth,，,2005,）,串珠状缝洞的地震正演模拟与反演解释,超覆尖灭潜山顶面,+,内幕串珠状溶洞的实际地震剖面（潜山顶面埋深大于,5000m,）,地质模型图，图中的地层尖灭和内幕溶洞（黑点）是重点研究目标,用,MIVMAS,方法获得的多尺度地震正演记录,模拟记录的声学波动方程偏移剖面,MIVMAS,地震数值模拟,Rock physics:uses and abuses,Laboratory measurements and empirical relations,实验室测量与经验关系,Verify theoretical results and provide input data to theories and models,验证理论结果及对理论与模型提供输入参数,Gather real rocks from the field,whereas theories assume universal rocks,从油田采集真正的岩石，而理论总是假设一个通用岩石,Simulate reservoir conditions and processes,模拟油藏环境及过程,But,但是,Small samples,need to measure many samples to derive statistical relationships(scaling problem),用的标本很小，需要测量很多标本而导出统计关系（尺度问题,）,Samples may be mishandled or damaged,标本有可能被误处理、破坏,Wrong data may have been gathered due to incorrect procedures,mishandling,or inexperience,由于错误的测量步骤、处理不当、或经验不足，所测的数据可能是错的,Examples:,例如,Poor measurement planning and experiments,测量规划不对,Over-drying clay-rich sands or shales,对含粘土的岩石过分干燥,Inaccurate or,wrong,data,不精确甚至是错误的数据,Rock physics:uses and abuses,Rock physics:uses and abuses,为负,为正,用现代技术测量的岩中的孔隙流体连通网络,垂直应力与垂直裂缝示意图,Poission,效应引起的垂直裂缝,S.Crampin,的定向应力流体饱和粒缘顺服裂缝模型，应力,S,H,=0,时，矿物颗粒边缘的裂纹呈自然分布，,S,H,=0.5,时，颗粒间的水平裂纹和小角度裂纹开始闭合，大角度裂纹开裂程度加大，,S,H,=1,时，水平裂纹进一步闭合，垂直裂纹进一步开裂，到达临界状态，并形成定向（垂直方向）顺服粒缘裂缝系统，应力,S,H,=3,时，超过临界状态，岩石将沿垂向破裂。,Poission,效应引起的垂直裂缝,Pore pressure(psi),Velocity(m/s),Vp,Vs,32%porosity,oil-saturated soft sands,From a university lab.14.7PSI=1,大气压力,Rock physics:uses and abuses,Rock physics:uses and abuses,32%porosity soft sand,ChevronTexaco Lab Repeat,QC the data you use,对你的数据进行质量监控,Dont always trust the data you get,不要总是信任你拿到的数据,P,波和,S,波的变化规律相反,!,From a commercial lab,ChevronTexaco Lab Repeat,26%porosity sandstone,Laboratory measurements,雪佛龙岩石物理实验室,ChevronTexaco Rock Physics Laboratories,Laboratory measurements,ChevronTexaco Rock Physics Laboratories,MTS,系统照片,MTS,岩石物性测试系统,（测 量,P,波 和 两 个 正 交 的 横 波）,成都理工大学岩石物性测试系统,Factors affecting seismic rock properties,Many factors influence seismic properties of sedimentary rocks,许多因素影响沉积岩石地震特性,Rock properties,Environment,Fluid properties,Lithology,岩性,Compaction,紧密度,Consolidation history,强固史,Cementation,粘结度,Bulk density,密度,Porosity,孔隙度,Pore shape,孔隙形状,Texture,结构,Age,年代,Clay content,粘土含量,Anisotropy,各向异性,Fluid type,流体类型,Fluid composition,流体成分,Viscosity,粘度,Wettability,可湿性,Phase,相态,Density,密度,Depth/overburden pressure,深度、覆盖压,Pore pressure,孔隙压,Temperature,温度,Saturation,饱和度,Frequency,频率,Reservoir process,油藏过程,Production history,生产史,Depositional environment,沉积环境,Stress history,压力史,Fracturing,裂隙,Red:discussed with examples,用例子讨论,Effects of,lithology,density,texture,岩性、密度、结构的影响,For a given porosity,dolomite has the highest velocities,给定孔隙度，白云岩具有最高的波速,Because seismic properties(impedances or velocities)overlap among,lithologies,rock physics constraints seismic lithology prediction,由于不同岩性的地震特性重叠，岩石物理可在地震岩性预测中提供约束,Dolostone,白云岩,1.41,4.0,3.0,2.0,1.7,1.6,1.5,0.33,0.24,0.18,0.10,0,7.0,0.50,0.49,0.47,0.44,Marine,sediments,海洋沉积,Soil,土壤,Wet,Sands,湿砂岩,Soft,shales,软泥岩,Limestone,石灰岩,Anhydrite,石膏,Gas,Sands,含气砂岩,Salt,盐岩,Shales,泥岩,Vp,/Vs,纵横波比,Poissons Ratio,波松比,Effects of,lithology,density,texture,Example:Lithology prediction in carbonates,例子：碳酸岩环境下的岩性预测,Lithology and porosity both vary in reef/margin settings,在珊瑚礁及其边缘环境下，岩性和孔隙度都可能变化,Similar P-wave impedances between porous dolomite and tight limestone,marl,or shale,有孔隙的白云岩和无孔隙的石灰岩、泥灰岩、泥岩具有相似的纵波阻抗,Costly exploration mistakes are often made drilling into“porosity events”,高费用的勘探错误经常发生在所谓的地震“孔隙显示”上钻井,鲕粒白云岩储层,中环状溶孔、新月形溶孔、鲕模孔和裂缝,鲕粒内新月形溶孔,鲕粒内环状溶孔,飞仙关组 溶孔与裂缝,普光,2,井岩样 溶孔与裂缝,Example:Lithology prediction in carbonates,Impedance ratio is a good indicator of lithology and porosity in carbonate rocks,波阻抗比可用来区分岩性和孔隙,P-P Seismic,Vp/Vs,2.0,1.5,1.0,Using Vp/Vs=(2*TintPS/TintPP)-1,:,Example:Porosity and solid bitumen,例子：孔隙度与固体沥青,Solid bitumen is a big problem in a giant carbonate reservoir.It reduces effective porosity,whereas seismic waves“see”the total porosity,在一个很大的碳酸岩油田中，固体沥青是一个大问题,By comparing seismic properties with those of“clean”carbonate,the amount of shift on the porosity axis gives the approximate bitumen content,通过与不含沥青碳酸岩的比较，孔隙度轴的移动量大体就是沥青的含量,含沥青,清洁的,Example:Porosity and solid bitumen,The derived bitumen content compares reasonably well with the laboratory measured values,导出的沥青含量与实验室直接测量的大致吻合,It seems that S-wave is better for bitumen content prediction,看起来在预测沥青时，,横波要比纵波好,Effect of pore fluids and saturation,孔隙流体及其饱和的影响,Rocks with less compressible pore fluids show higher P-wave impedances and velocities,带有非可压流体的岩石具有较高的波阻和波速,S-wave properties are hardly affected by pore fluids,横波基本不受流体的影响,Rocks with less compressible pore fluids show higher,Vp,/Vs ratio,带有非可压流体的岩石具有较高的纵横波比,Gas,Light oil,Heavier oil,Fresh water,Saline water,Compressibility,可压性,Bulk modulus,Gas 0.01-0.2 GPa,Condensate 0.2-0.6 GPa,Light oil 0.6-1.4 GPa,Heavier oil 1.4-2.2 GPa,Fresh water 2.25 GPa,Saline water 2.3-3.5 GPa,Effect of pore fluids and saturation,Fluid effect is the key to 4D,AVO/DHI,and oil-water contacts 流体效应在AVO，直接找油、和油水接触面中起主要作用,However,fluid effect is“shadowed”or complicated by rock properties:Softer rocks show larger fluid effect,但是，流体效应往往被岩石本身特性遮盖或复杂化：软的岩石显示较大的流体效应,harder,softer,Effect of,pore fluids and saturation,Example:Gulf Coast water drive,例子：墨西哥湾水驱油,High porosity soft sand,高孔隙度软沙,High salinity brine,高盐度水,High GOR light oil,高溶气轻油,Water drive increases the P-wave impedance by as much as 18%,while hardly affects the S-wave impedance,水驱油使纵波阻抗升高达百分之十八，而对横波阻抗几乎没什么影响,A few words on pressure,关于压力,In a reservoir,there are always two types of pressures at work:the overburden pressure and the pore(reservoir fluid)pressure,油层中总是存在两种压力：覆盖压与孔隙（流体）压,Overburden pressure,:pressure caused by rock mass=,r,gz,(gradient,1.0 psi/ft),上覆地层压力是由油层以上的岩石引起的,.(14.7psi=1.0,大气压力,=0.1Mpa),Pore(reservoir fluid)pressure,:pressure caused by fluid column=,r,f,gz,(gradient,0.46 psi/ft),孔隙压是由油层以上的流体引起的,Net pressure(effective,differential),:the difference between the two pressures=(,r,-,r,f,)gz,(gradient,0.54 psi/ft),净压力（有时也叫有效压）是两者之差,4.3%,1000 psi,0.5%,1000 psi,1000 psi,5.3%,0.5%,1000 psi,1000 psi,1000 psi,3.5%,0.4%,More words on pressure,Pressure effect on seismic properties is higher in low net pressure ranges,due to the closure of thin pores and loose grain contacts,由于窄孔隙的关闭和岩粒间的拟合，压力对地震特性的影响,在低净压区中较大,Knowing the pressure regime is important in time-lapse reservoir monitoring(4D and time-lapse AVO),了解压力状态,对间时地震油藏监测非常必要,Rocks from different fields have different pressure responses which can be derived only from lab measurements,不同油田的岩石对压力的响应是不同的，这种响应一般只能在实验室得到,Effect of,temperature,温度的影响,Seismic properties decrease as temperature increases in rocks,岩石的地震特性随温度的升高而降低,The decreases are caused by the changes in pore fluid properties,rock properties,and rock and fluid interactions,这种降低是由孔隙中流体特性、岩石特性、及岩石,-,流体的相互作用的变化引起的,Seismic responses to temperature is the key for 4D seismic monitoring of thermal floods,地震的温度响应是四维地震监测热采过程的主要基础,Effect of,temperature,pre-steam,difference,post-steam,Example:Seismic monitoring of steam flood at,Duri,例子：杜里油田的注蒸汽地震监测,What about anisotropy?,各向异性,In reservoirs with,thick cap shales,ignoring anisotropy in seismic imaging often yields depth,misties,blurred structures and fault images,如果泥岩层很厚，在地震成像中忽略各向异性将出现深度闭合差，使构造和断层模糊不清。,From Meadows and,Abriel,1994,Niger Delta:3D Anisotropic PSDM,尼日尔三角洲三维各向异性迭前深度偏移,Courtesy of Keith Hawkins,Veritas,DGC,5 s,6 s,Anisotropic PSDM,Isotropic PSDM,地震各向异性的直观理解,S1,S2,G1,G2,2,1,Leon Thomsen,（,2002,）对地震各向异性的定义：,Seismic Anisotropy is defined to be:“,the dependence of seismic velocity upon angle.”,地震波速度与入射角有关。,图,1,上、下层介质物性有差异，射线为折线，每个射线的入射角不同，波的传播速度不同，出现各向异性,图,2,上、下层介质物性无差异（或差异很小），射线为直线，射线的入射角不同，波的传播速度相同，显示各向同性,由地震波各向异性的定义和图,1,与图,2,可以回答常见的如下问题：,（,1,）为什么上、下层各自均匀，还会出现地震各向异性？（射线为折线，盖层愈厚，各向异性影响愈大）,（,2,）做了地震深度偏移后，为什么还会出现地震各向异性？,（不可能每道给不同的速度）,（,3,）为什么主要考虑目的层上方地层的各向异性？,HTI,与,VTI,介质,HTI,VTI,V,2,V,1,各向异性系数：,Laboratory measurements,各向异性的实验室测量,For transversely isotropic rocks,a minimum of 5 independent measurements are required to obtain the 5 independent elastic stiffness,对于,横向各向同性,岩石来说，要对每一块岩石要至少测五次才能得到五个独立的弹性参数,C11,C33,C44,C66,and C13,TI,（,Transverse Isotropy,）介质,VTI,介质有五个独立参数,C11=C22,、,C44=C55,、,C13=C23,、,C12=C11-2C66,五个独立参数为,:,C11,C33,C44,C66,and C13,HTI(,或,EDA),介质也有五个独立参数,C,12=,C,13,、,C,22=,C,33,、,C66=C55,、,C23=C33-2C44,。,五个独立参数也为,:,C11,C33,C44,C66,and C13,Transverse isotropy-3-plug method,Traditionally,three,plugs orientated at different angles have to be measured to obtain the five independent elastic stiffness,一般说来，要取三个不同角度的岩芯来进行测量才能得到五个独立弹性参数,The equations have the simplest form when,q,=0,o,45,o,and 90,o,上页中的关系式在三个岩芯角度为零、四十五、九十度时最为简化,Transverse isotropy-3-plug method,P,S1,S2,C33,C44,C11,C44,C66,C13,Anisotropy,各向异性,Because shales are,nonpermeable,it is extremely time-consuming measuring shale anisotropy in the lab,由于泥岩的渗透率特低，实验室中测量泥岩的各向异性特别费时,We designed an apparatus that saves 2/3 of the lab time,王之敬等设计了一种设施可节约三分之二的时间,Transverse isotropy-single-plug method,We designed and built a device that requires only,one,core plug to obtain all the five elastic constants,王之敬等人的新方法只需测一个岩芯就可得到五个弹性参数,This method has been rigorously validated and tested using materials with know properties,王之敬等,用已知材料对这个方法进行了各种测试,纵波各向异性,橫波各向异性,Data from 100 data points of shales,200 for sands,and 200 for carbonates,一百多泥岩数据点、两百多砂岩数据点,、,两百多碳酸岩数据点,Shales,泥岩,e,d,s,g,h,Anisotropy parameters and relationships,各向异性参数及其关系,Sands,砂岩,e,d,s,g,h,Carbonates,碳酸岩,Anisotropy parameters and relationships,极化对称坐标介质,(VTI,HTI),的,Thomsen,各向异性系数,的值是无量纲的,一般小于,0.5,当地震炮检距较大时,表示各向同性介质与各向异性介质中动校时差的差异,.,注意,:,和,的定义不统一,Challenges,岩石物理所面临的挑战,General observation,大体状况,Rock physics is way underused in reservoir charac