【作者】 李鹭光；

【导师】 罗平亚；

【作者基本信息】 西南石油学院 ， 油气田开发工程， 2004， 博士

【摘要】 随着全世界对天然气能源需求量的不断增大，常规天然气藏的产量和储采比都显示出日益降低的趋势，非常规天然气资源被认为是最有希望的能源补充，因此加快低渗气藏的勘探开发是本世纪能源工业发展的必然趋势。 经过四十余年的勘探开发，四川已经成为了我国重要的天然气工业基地之一。随着四川和西南地区经济的不断发展，对天然气的需求量越来越大，但是，四川盆地气藏储层具有低渗、致密的大背景，低渗、特低渗储层在四川盆地气藏中占有相当比例，在现有剩余可采储量中，有1／3以上属于低渗、特低渗储量。这类气藏开发工艺复杂、储量动用难度高、稳产条件差、单井产能低、开采综合效益差。为了从根本上解决四川盆地低渗气藏开发这一难题，本文运用地震、测井、油藏工程、渗流力学、数值计算和实验研究等技术和理论开展四川盆地低渗透气藏储层特征、低渗透储层气体渗流机理、低渗透气藏试井分析方法、低渗透气藏储层改造技术、低渗透气藏储层保护技术及水平井、欠平衡钻井等方面的理论、实验和应用研究，并结合四川盆地低渗气藏已有开发技术和应用成果，进行了系统分析和总结，形成了一套适合四川碳酸盐岩和砂岩低渗透气藏的开发技术体系，为四川盆地低渗透气藏的高效开发打下了必要的基础。本文取得的主要研究成果如下： (1)在对四川典型低渗透气藏储层岩性、孔隙结构特征、裂缝类型和分布特征等研究的基础上，以岩石物性参数、孔隙类型和孔隙结构参数为主要定量依据，并综合考虑裂缝发育程度及其对储层渗透能力的改善作用，提出了将四川盆地低渗透储层划分为低渗、特低渗两大类，该划分既符合四川盆地低渗透气藏的实际情况，又能较好地指导四川盆地低渗透气藏的合理开发。 (2)首次建立了由宏观裂缝、微细裂缝和显微裂缝及孔隙喉道共同组成低渗储层四级渗滤通道的渗流模式，基质孔隙喉道和显微裂缝是储层储渗的基础，储层产能及渗流特征决定于四级渗流通道的搭配关系。该模式对低渗气藏的开发具有重要的指导意义。 (3)针对四川低渗储层特点，充分利用构造分析、地震反演、模式识别等储层预测技术，提出了裂缝发育综合强度指数评价等一整套裂缝和储层横向预测方法和技术，进一步完善和发展了低渗透储层评价和有利区块预测技术。这些技术在平落坝须二、白马～松花蓬莱镇和五百梯石炭系气藏裂缝～孔隙发育区预测工作中取得了较显著的效果。 (4)对低渗储层单相和残余水条件下气体低速非达西渗流机理进行了较为全面和深入的实验研究，掌握了低渗储层单相气体和残余水条件下气体的低速非达西渗流特征。该四川盆地低渗透气藏开发技术研究项成果对低渗气藏开发技术的研究具有重要的指导意义。 (5)在低渗储层低速非达西渗流机理研究的基础上，引入启动压差和临界压力梯度两个特征参数，建立了描述低渗介质低速非达西渗流的数学模型，并成功实现了求解，在此基础上，建立了低渗透气藏的试井分析方法，从而为低渗透气藏开发的动态监测和储层改造的评层选井提供了技术保证。 (6)通过对不同类型低渗透储层酸化的机理研究，提出了低渗透储层“通缝扩喉”改造的新思路，即针对孔隙胶结物和裂缝充填物矿物成分的特点，合理选择不同酸液配方和施工参数进行微观基质酸化，从而提高基质酸化的效果。 (7)针对四川盆地低渗白云岩储层的地质特点，开发了三套新型的深穿透酸压裂工作液体系(新型胶凝酸、助排剂和降滤失酸)。并研究配套了以交替泵注为主的深穿透酸压工艺技术。该项成果为四川盆地低渗透碳酸盐岩储层的增产改造提供了新的工艺技术手段。 (8)针对八角场气田香四气藏、平落坝须二气藏和白马一松华地区的蓬莱镇气藏以砂泥岩薄互层为主的厚层碎屑岩储层，从施工设计、泵注技术和全缝支撑等方面进行了研究，形成了一套在这类储层中有较好效果的高缝压裂和全缝支撑技术。现场应用效果显著。 (9)针对四川低渗气田纵向上具有多产层的特点，研制成功并配套试验完善了两套适合不同井况的分层改造、分(合)层开采的增产措施及其施工技术，取得了良好的工艺效果。 (10)在储层潜在损害因素研究的基础上，对钻井完井液、储层改造工作液损害储层机理进行了全面评价，为钻井及储层改造过程中四川盆地低渗储层保护技术路线的制定和保护措施的优化奠定了坚实的基础。 (11)针对四川盆地碳酸盐岩和碎屑岩低渗气藏的地质特征，筛选和研制出了有利于储层保护的钻井液和储层改造工作液配方，形成了适合四川盆地特点的低渗气藏储层保护特色技术，在应用中已经取得了较明显的效果. (12)欠平衡钻井技术在邓西3井、渔南1井及井浅2井取得重大勘探突破表明，在四川盆地低渗气藏勘探开发过程中，欠平衡钻井配套技术对于发现和保护油气层具有十分显著的效果，从而为四川盆地低渗透气藏的勘探和开发取得全面突破开辟了一条新的、具有重要指导意义的途径。 (13)水平井技术是四川盆地低渗气藏实现高效开发的必需技术。磨75一H水平井的成功完成，并获得显著的技术经济效益，必将推动水平井技术在四川盆地低渗气藏开发中四川盆地低渗透气藏开发技术研究的?更多还原

【Abstract】 With a gradually increasing of demand of natural gas in the world, the production and reserve-production ratio of conventional gas reservoir appearing a gradual decline, unconventional gas resource is considered as the most hopeful resource supplement. Thus accelerating the exploration and development of low permeability gas reservoir becomes an inevitable trend of the energy industrial development in the century.Sichuan has become one of the most important industrial gas bases in China through over forties years of exploration and development. With the unceasing development of economy in Sichuan and Southwest region, the demand of natural gas is getting more and more. However, gas reservoirs in Sichuan Basin are characterized by low permeability and tight. There are plenty of low permeability and extremely low permeability reservoirs. More than one third of reserves belong to low permeability and extremely low permeability reserves among the existing residual recoverable reserves. In general, these kinds of gas reservoirs are characterized by complicated development techniques, difficult producing reserves, poor stable-production condition, low production in single well and bad comprehensive production efficiency. In order to solve the problem of development of low permeability in Sichuan Basin, this paper adopt some techniques and theories such as seismic, well logging, reservoir engineering, percolating mechanics, numerical simulation and laboratory research to perform the theoretical, experiment and application researches including reservoir characteristics, percolating mechanism, analysis method of well test, reservoir reform techniques, reservoir protection techniques and horizontal well as well as unbalanced drilling techniques in low permeability reservoir. A set of development technical system has been formed adapting to carbonate and sandstone in low permeability reservoir in Sichuan, which has laid a stable foundation for efficient development of low permeability reservoir in Sichuan. The major research results are as follows:1. On the foundation of research for reservoir lithology, characteristics of pore structure, type and distribution of fracture of typical low permeability reservoir in Sichuan, taking the parameters of physical property, type and structure of pore as major quantitative basis, and with comprehensive.consideration of degree of fracture growth and its important role in the reservoir permeability, this paper has advanced the method of low permeability reservoir ofdividing into low permeability and extremely low permeability .which accord with the fact of low permeability reservoir in Sichuan.2. his is the first time to establish percolating pattern of the quartemary percolating channel for low permeability reservoir composed of macrofracture, fine fracture and microfracure as well as pore throat. And the matrix pore throat and microfracture are the foundations of storage and percolating in reservoir. The reservoir productivity and percolating characteristics depend on the correlation of the quarternary percolating channel. The pattern is significant to development of low permeability reservoir.3. For the characteristics of low permeability reservoir, the paper have made good use of reservoir techniques including structure analysis, seismic inversion and pattern recognition and proposed a set of fracture and reservoir lateral predictions method and techniques including the comprehensive evaluation index of fracture growth, which improve and develop reservoir evaluation and favorable block’s prediction in low permeability reservoir. Remarkable results have been gained in the prediction in fracture and pore growth areas of Xu2 in Pingluoba, Carboniferous reservoir of Wubaiti and Penglaizhen Formation in Baima-Songhua.4. Overall and thorough experiment research for low-velocity non-Darcy percolating mechanism has been made under single phase gas and residual water in low permeability, and low-velocity non-Darcy percolating characteristics have been realized. The result is instructive更多还原