【作者】 崔彦立；

【导师】 汤达祯；

【作者基本信息】 中国地质大学（北京） ， 油气田开发工程， 2010， 博士

【摘要】 火山岩油藏压裂是国内外储层改造面临的新课题,没有成熟的模式。火山岩地层发育的天然裂缝和局部结构差异将导致压裂施工中高滤失、高停泵压力梯度及近井高摩阻、多裂缝等问题,使人工裂缝的扩展有别于均质地层。牛东油藏复杂的岩性、储集结构及物性、含油性和力学性质的强非均质性,决定了压裂改造机理不同于砂岩油藏,表现为高应力、高滤失、高缝内扭曲、难控缝等技术难题。全程加砂充填法压裂技术是结合牛东裂隙岩体压裂地质和工程特征创新的现场实用技术,是针对裂隙岩体的全新技术理念。其主要原理:引入岩体力学等观点,在水力造缝过程中,应用压裂液、支撑剂和施工参数的优化技术,张开低角度的天然结构面;通过全程加砂降滤和堵塞支缝形成水力主裂缝增压腔,依靠有序提高缝腔内净压力以增加近井和远井的结构面张开度和延伸距离,形成以井筒为中心、沟通近井或远井储集结构面、具有渗流通道作用的裂缝导流系统,同时增加充填厚度,减少隔层脆性断裂和支撑剂嵌入等作用。本文内容主要包括五个部分。第一部分是牛东油田地质和油藏特征研究,重点研究了成岩、成藏模式、储油模式和分区渗流模式。第二部分是应用岩体力学等理论,研究牛东火山岩裂隙岩体的工程特征。重点是结构面特征对水力造缝的特殊力学作用,如脆性断裂效应、嵌入效应、滤失效应、地应力屏蔽效应、敏感性伤害作用等。第三部分总结了国内火山岩油气藏压裂技术现状及牛东前期压裂技术应用情况,重点分析了牛东前期按照砂岩压裂模式压裂施工存在的高砂堵率等问题的机理。第四部分研究了裂隙岩体水力造缝增压压力腔机理,主要是分析了连续介质常规压裂理论的不适应性、增压腔造缝模式形成与延伸机理、多裂缝等效滤失的G函数导数诊断等内容;第五部分研究了全程加砂充填法现场应用技术研究,总结了火山岩压裂造缝和滤失的特殊机理及三种施工模式,分析论证了压裂设计与施工等配套技术及应用井例。经过牛东火山岩储层的规模应用,有效解决了高砂堵率、高用液量、低砂比和短有效期等火山岩压裂难题,压裂施工成功率、压裂液体效率、增产效果得到大幅度提高,并对提高同类油藏的水力压裂技术水平具有重要意义。更多还原

【Abstract】 Hydraulic fracturing for well stimulation in the volcanic reservoir is a new problem of the world,having no grown-up mode.During fracturing in volcanic reservoir,the difference between volcanic reservoir and homogeneous reservoir is great,because natural fissures growed and regional structure variation cause high filtration in fractures,large pressure gradient of pump,nearwell high friction resistance and multi-factures.The mechanisms on volcanics fracture of Niudong volcanic oilfield,are very different from sandstone-formation fracture,exhibiting at technical puzzles such as high stress,high leakoff rate,high contortion in fracture and fissure’s hard-controlling.This difference results from the complication of its lithological association and reservoir structure,the great heterogeneity of its osmose,oiliness and mechanical character.Fracture technology of full term gravel input compaction method combine fracture and geology of fractured rock in Niudong oilfield with engineering feature innovation, in view of brand new technology concept of fractured rock.The main principle is introduced rock mass mechanics view-point,in the course of hydralic created fracture, applied optimum technology of fracturing fluid,proppant and operation parameter, expanded low angle natural discontinuity,by means of decreasing filtration of full term gravel input and blocking up fracture,formed booster cavity of hudralic main fracture, improved net pressure of fracture cavity,increased structural surface expansion and extended distance in the near wellbore and far wellbore,formed wellbore,linked up near wellbore or far wellbore to accumulate structural surface,formed fracture diversion system with filtering flow channel function,at the same time,increased filling thickness, decreased barrier brittle fracture and proppand embedment.The paper mainly consists of five sections.The first section is Niudong oilfield geology and reservoir feature research,stressly research rock and reservoir mode,oil storage mode and partition filtering flow mode.The second section is applied rock martix mechanics theory,research engineering feature of Niudong volcanic fractured rock, mainly research structural surface feature cause effect on special mechanics of hydralic created fracture,such as brittle fracture effect,embedding effect,filtration effect,earth stress screening effect,sensitivity damage action.The third section sum up present stiuation of volcanic reservoir fracturing technology and earlier days fracturing technology application in the Niudong oilfield,according to sandstone fracturing mode, mainly analyze existing high sand bridge ration of fracturing operation in the earlier days of Niudong oilfield.The fourth section research hydralic created fracture supercharge pressure cavity mechanics of fractured rock mass,mainly analyze inadaptability of conventional fracturing theory for continuous medium,created fracture of booster cavity formation and extended mechnics,G functional derivative diagnosis multi-fracture equivalent filtration.The fifth section research field application technology of full term gravel input compaction method,sum up particular mechanics of created fracture and filtration of volcanic rock fracturing and three kinds of operation mode,demonstrate fracturing design and operation technology and application.Application in volcanic oil reservoirs of Niudong demonstrates that this technology has efficiently resolved conundrums of volcanics fracture such as high sanded-up ratio,high charge for using liquid,low sand ratio and brief effective period, shows that the success rate of fracturing and efficiency of hydraulic fracturing’s liquid increases significantly with obvious production increment and large financial benefit, implying that the technology worth theoretically and realistically to promote the application of hydraulic fracture in naturally fractured reservoirs or improve the massive fracturing treatment and development of volcanic reservoir.更多还原