常规测井技术识别火山岩裂缝方法研究——以松南火山岩为例  

Study on method of identifying volcanic rock fractures by conventional logging technology——A case study on Songnan volcanic rock

作　　者：刘双莲 LIU Shuanglian(Sinopec Research Institute of Petroleum Engineering, Beijing 102206, China)

机构地区：[1]中国石化石油工程技术研究院,北京102206

出　　处：《非常规油气》2022年第4期16-22,共7页Unconventional Oil & Gas

基　　金：中石化科技部项目“中石化测井软件平台升级及应用子系统研发”(PE19012-2)。

摘　　要：利用成像测井识别裂缝是目前常用的方法。但成像测井技术常用于探井或关键井,难以在开发井中普遍应用。当流体与裂缝共存时,测井信号的相互叠加或消弱,影响裂缝的识别,因此如何利用常规测井资料识别裂缝,是当前需要攻克的难题。该文从测井原理出发,分析了火山岩不同裂缝类型及裂缝与气体共存时的测井曲线响应特征。在裂缝发育层段,补偿密度值通常低于骨架密度,补偿中子曲线值显示为高值。当裂缝中存在气体,常规测井中的双侧向电阻率曲线正差异明显,深浅侧向曲线间如同“双轨”,补偿密度值变低,补偿中子与声波时差值变大。当裂缝中不含气体且为低角度裂缝时,双侧向电阻率曲线在低角度裂缝处基本重合,补偿密度、补偿中子与声波时差无明显异常显示;裂缝为高角度缝时,双侧向电阻率曲线正差异明显,且在裂缝边界处具收敛性,密度曲线呈齿化状且曲线值略有降低,中子与声波时差无明显异常显示。At present,imaging logging is commonly used to identify fractures.However,it is often used in exploration wells or key wells,which is difficult to be widely used in development wells.When fluid and fracture coexist,the overlapping or weakening of logging signals will affect the identification of fractures.Therefore,how to use conventional logging data to identify fractures is a difficult problem to be solved at present.Based on the logging principle,this paper analyzes the logging curve response characteristics of volcanic rocks with different fracture types and the coexistence of fractures and gas.In the fracture development interval,the compensation density value is usually lower than the skeleton density,and the compensation neutron curve value is shown as a high value.When fracture bearing gas,the positive difference of dual lateral resistivity curves in conventional logging is obvious,with“double track”phenomenon,the density decreases,but the acoustic time difference and neutron increases.When there is a gas free fracture with low angle,the dual lateral resistivity curves basically coincide at the low angle fracture,and there is no obvious abnormal display of density,neutron and acoustic time difference;On the contrary,the positive difference of dual lateral resistivity curve is obvious with a high angle fracture,and it has convergence at the fracture boundary,the density curve is toothed and it’s curve value decreases slightly,there is no obvious abnormal display of neutron and acoustic time difference.

关 键 词：火山岩 常规测井 裂缝类型 识别方法 双侧向电阻率 

分 类 号：TE121.1[石油与天然气工程—油气勘探]