文章检索
首页» 过刊浏览» 2016» Vol. 1» Issue (3) 342-352     DOI : 10.3969/j.issn.2096-1693.2016.03.029
最新目录| | 过刊浏览| 高级检索
3D FEM随钻电磁波电阻率测井响应影响因素研究
姜明,柯式镇,李安宗,康正明,李成远,张文豪
1中国石油大学(北京)油气资源与探测国家重点实验室,北京102200 2中国石油大学(北京)地球物理与信息工程学院,北京102200 3中国石油集团测井有限公司随钻测井仪器研究中心,西安 710061
Factors effecting simulation of the response of LWD electromagnetic wave resistivity based on 3D FEM
JIANG Ming, KE Shizhen, LI Anzong, KANG Zhengming, LI Chengyuan, ZHANG Wenhao
1 State Key Laboratory of Petroleum Resources and Prospecting, China university of petroleum, Beijing 102200, China 2 College of Geophysics and Information Engineering, China university of petroleum-Beijing, Beijing 102200, China 3 China Petroleum Logging Co. Ltd., Xi’an 710061, China

全文:   HTML (1 KB) 
文章导读  
摘要  影响随钻电磁波电阻率测井仪器响应的因素主要来自两方面:一方面是自身结构因素,包含线圈、天线凹槽、盖板、钻铤等,这些因素通过影响接收线圈感应电动势的幅度,进而对电阻率测量结果产生影响;另一方面因素来自外界环境,包括井眼泥浆、围岩、侵入、介电常数以及地层各向异性等,测井过程中的仪器响应,是对井下多种不同介质的综合响应,为了达到探测原状地层电阻率的目的,需要扣除其它因素对仪器响应的影响。因而研究影响随钻电磁波电阻率测井响应的因素,对测井资料的解释与应用是十分必要的。本文以随钻电磁波电阻率仪器WPR (Wave Propagation Resistivity)为算例,建立真实的3维仪器结构,采用3维有限元3 D FEM (Three-Dimensional Finite Element Model)方法,针对真实仪器自身结构以及外界环境因素对仪器响应造成的影响进行了数值模拟,并利用解析解对本文的数值解进行了验证。感应电动势绝对值随着线圈半径、线圈凹槽宽度、天线槽长度、盖板占空比增大而明显增大;随着凹槽深度增加而减小。其中,浅探测模式受以上因素影响较深探测模式更大。此外,感应电动势绝对值受金属钻铤的电导率影响较小。在外界环境因素方面,井眼与泥浆存在使视幅度比电阻率偏小,视相位差电阻率偏大;泥浆电阻率越大,对仪器响应造成的影响越小;各向异性使视幅度比电阻率与视相位差电阻率均偏大;泥浆侵入、围岩、介电常数以及各向异性因素使视幅度比电阻率与视相位差电阻率在数值上差异逐渐增大;泥浆侵入使视相位差电阻率与视幅度比电阻率差异先增大再减小;介电常数影响在高阻地层中更加明显,其中视相位差电阻率受影响更大。
服务
把本文推荐给朋友
加入我的书架
加入引用管理器
关键词 : 随钻测井; 随钻电磁波测井; 仪器结构; 环境校正; 有限元
Abstract

  Both of the structure of logging tools and environmental factors affect the response of LWD (Logging While Drilling) electromagnetic wave resistivity tools. The structures of the receiver coil, coil groove, coil cover and metal mandrel impact on the amplitude of the induced voltage in the receiver coil, and the measurements of resistivity are affected indirectly. In terms of environment factors, the responses of borehole-mud, surrounding rock, drilling fluid invasion, dielectric properties and anisotropy contribute to the real response of logging tools. These responses corresponding to environment factors should be removed to obtain the real response of the undisturbed formation. Thus, it is indeed imperative to study the effects of tool-structure and environments factors for the interpretation and application of logging information. In this paper, an example of numerical simulation of a wave propagation resistivity tool based on a 3D FEM (Three-dimensional Finite Element Model) method is introduced. We have conducted the numerical simulation of the tool-structure and environments factors based on the real structure of the logging tools. The absolute value of the induced voltage rapidly increases with an increase of coil radius, width of coil groove, length of coil slot, and space proportion of cover. The absolute value decreases with an increase of the depth of the coil groove. The shallow mode is more susceptible than the deep mode to the above factors. Moreover, the absolute value has a weak relation with the conductivity of the metal drill collar. In the respect of environmental factors, the apparent amplitude ratio resistivity decreases while the apparent phase shift resistivity increases due to the borehole-mud while the effects of mud become weaker as the mud resistivity increases; both in the apparent amplitude ratio and the apparent phase shift resistivity increase due to the anisotropy. The value difference between the apparent amplitude ratio and apparent phase shift resistivity increases owing to the effects of the mud invasion, surrounding rock, dielectric or anisotropy. The difference of the two above resistivity values increases at first, and then decreases due to the effect of mud. The influence of dielectric properties becomes more significant in high resistivity formations. Apparent phase shift resistivity is more sensitive than the apparent amplitude ratio resistivity for dielectric effects.

Key words: LWD ; electromagnetic propagation resistivity logging ; tool structure ; environment correction ; finite element model
收稿日期: 2016-07-06     
PACS:    
基金资助:国家油气重大专项(2011ZX05020-002)资助
通讯作者: wksz@cup.edu.cn
引用本文:   
姜明,柯式镇,李安宗,康正明,李成远,张文豪. 3D FEM随钻电磁波电阻率测井响应影响因素研究[J]. 石油科学通报, 2016, 1(3): 342-352. JIANG Ming, KE Shizhen, LI Anzong, KANG Zhengming, LI Chengyuan, ZHANG Wenhao. Factors effecting simulation of the response of LWD electromagnetic wave resistivity based on 3D FEM. 石油科学通报, 2016, 1(3): 342-352.
链接本文:  
版权所有 2016 《石油科学通报》杂志社