The Tight oil reservoir has the characteristic of low porosity (average of 8%), ultra-low permeability (average of 0.1 mD), low abundance and high clay content. The conventional fracturing techniques in exploration area was not successful in some cases, a novel series of horizontal well energy-storage fracturing techniques is proposed to improve the conventional fracturing technique, which based on increasing modified volume and replenishing formation energy. This technology involves in spacing optimization along the horizontal well section, optimization of fracturing fluid parameter, and forming complex network cracks. Afterwards, well shut-in can store energy and contribute to oil/water replacement. A total of 6 horizontal wells with 73 sections were tested in the field with successfully oil testing up to 95% after the techniques, which produces a good industrial oil flow. Furthermore, the single-well production can approach 8-10 times higher than that from the straight wells and 2-3 times higher than that from other horizontal wells in the same well block. The energy-storage fracturing technique provides a technical support for prospection and development of tight oil reservoir.
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