Aiming at the difficulties of ultra-shallow dense reservoir, involving complex artificial fracture morphology, difficult gel⁃out of fracture fluid, low producing energy and difficult fracturing, Chang 3 ultra-shallow reservoir in Weibei oilfield was taken as study object. Through theoretical research and field operation, fracture morphology recognition method for ultra-shallow dense res⁃ervoir was researched. The results show that, when buried depth is less than 450 m, the main fracture type is horizontal fracture, however, when buried depth is more than 550 m, vertical fracture form. According to the characteristics of the direction well, me⁃chanical differential pressure is regarded as overall fracturing leading technology. Combined with indoor tests, low concentration guar gum fracturing fluid formula system of Chang 3 ultra-shallow reservoir in Weibei oilfield was developed and ultra-low temper⁃ature compound gel breaking technology was as the key object. After applying new technologies to testing 69 wells, the transforma⁃tion efficiency is 100 %, thereby realizing technology breakthrough of overall fracturing development in this block and providing technical basis for other ultra-shallow reservoir development.%针对超浅层致密油藏人工裂缝形态复杂、压裂液破胶困难、地层能量低压裂难度大等难点，以渭北长3超浅层油藏为研究对象，利用理论研究及现场测试等方法，研究超浅层致密油藏裂缝形态识别方法。结果表明：埋深小于450 m主要形成水平裂缝，大于550 m时形成垂直缝，根据定向井特点优选了机械分压作为整体压裂主导工艺，结合室内实验，评价出渭北长3超浅层低浓度胍胶压裂液配方体系，并重点研究了超低温复合破胶技术。现场试验69口井，改造有效率100%，实现了区块整体压裂开发的技术突破，也为其它超浅层油藏开发提供了技术依据。
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