摘要
大庆探区深层火山岩储集层孔洞-裂缝发育,施工中存在多条裂缝同时破裂延伸的特点,导致施工易早期砂堵,压裂成功率低、改造规模小、增产效果差。通过对深层火山岩地质特征的研究,建立了火山岩压裂破裂和延伸模型,引入了与时间相关的漏失因子、尖端因子和模量因子,描述了特殊岩性地层主裂缝与微裂缝的开启与延伸过程,在此基础上,探讨了压裂过程中存在的"三高"现象(即停泵压力梯度高,近井摩阻高和滤失系数高)的评价方法,并通过现场实践,形成了以胶塞处理近井高摩阻、粉砂封堵天然裂缝以及调整前置液比例、多段粉砂段塞注入为主的综合处理措施,使火山岩气藏压裂成功率由以往的36.0%提高到目前的90.0%以上,提高了火山岩气藏的压裂增产效果。
Pores, cavities and fractures are well-developed in deep volcanic reservoirs. The simultaneous break and extension of multi-fractures in treatment caused early stage sand-block, low fracturing success ratios, small treatment scales, and bad stimulation results. Based on the geologic characteristics of the deep volcanic rocks, this paper establishes a fracturing break and extension model of volcanic rocks, introducing with time-relevant leaking factor, peak factor and modulus factor. The model is used to better describe the process of initiation and extension of major fractures and micro-fractures. On this basis, the evaluating method for the ＂three highs＂ of pump off pressure gradient, near well friction resistance and leakoff coefficient is studied, and through field practices, integrated processing measures are formed; use rubber plugging to deal with near-well high friction resistances, use silts to seal natural fractures, adjust prepad fluid ratios, and inject multisection silt slugs. The success ratio of volcanic rock gas reservoir fracturing is raised to 90.0% from the past 36.0%.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2009年第4期529-534,共6页
Petroleum Exploration and Development
基金
中国石油勘探与生产分公司项目"火成岩等特殊储集层试油(含措施改造)配套技术研究"
