大庆油田深层天然气井（含CO2）增产改造技术的新进展

THE NEW PROGRESS OF STIMULATION TECHNOLOGY IN DEEP GAS WELL （CO2-BEARING） IN DAQING OILFIELD

火山岩储层一般都具有低孔、低渗的特点，自然产能低，需压裂改造才能获得工业油气流。常规的压裂增产技术不能适应火山岩储层，主要表现为人工压裂裂缝启裂和延伸机理难于认识，部分储层高压下仍无法破裂与延伸，裂缝复杂、裂缝窄，无法加入支撑剂，压裂优化设计缺乏针对性；没有耐高温的压裂液体系。为提高压裂优化设计的针对性和提高压裂液携砂性能，建立了火山岩压裂破裂与延伸物理、数学模型，形成了火山岩天然裂缝储层压裂设计基础理论；配套了超高温压裂液体系，满足了压裂施工的需要；形成了测试压裂现场快速解释诊断技术、火山岩人造裂缝延伸控制技术，有效地保证了主裂缝的形成，大大提高了施工成功率。为徐深气田提交火山岩天然气2457．45×10^8m^3探明储量提供了强有力的技术保障。

Volcanic reservoirs, generally with low porosity, low permeability and low natural productivity, need fracturing stimulation to obtain commercial oil and gas flow. Conventional fracturing stimulation technology is not suitable to volcanic reservoir, because the fracture open mechanism and fracture extension mechanism under artificial fracturing are difficult to understand, breakdown and extension in partial reservoirs are still incapable under high pressure, fractures are complex and narrow, it is unable to add proppant, the design for fracturing optimization is lacking of directivity, and there is no fire-resistant fracturing fluid system. In order to improve the directivity of the design for fracture optimization and the carrying capacity of fracture fluid, the physical model and mathematical model for the artificial fracturing and extension in volcanic were established, and the basic theory of fracturing design for naturally fractured volcanic reservoir was formed. Ultra-temperature fracturing fluid system was established,which meets the requirement of fracturing implementation. The minifrac on-site rapid interpretation and diagnosis technology and the artificial fracture extension control technology were formed, which effectively ensure the generation of major fracture, significantly improve the success rate of fracturing, and provide strong technical support for Xushen gas field to submit 2457.45 × 10^8m^3 proven gas reserve from volcanic.