Analysis and Application of Multi-Stage Fracture Stimulation in Yanchang Oilfield

Abstract:

The continental shale of Yanchang Formation in Ordos Basin is in complex facies. Being high in mud and low in brittle mineral, the reservoir quality is poor. Therefore multi-stage fracture stimulation has been applied there in horizontal wells. The fracture interval in horizontal well is a critical parameter and it has a great influence on the fracture interaction. Since the fracture interaction can directly determine the extent to which the stimulated reservoir volume (SRV) expands, its most necessary to study the mechanism of the effect. For this, a mathematical model based on elastic mechanics would be given. By using this model, we analyzed the influences on the fracturing work. An analysis of field data from Yanchang Oilfield shows that proper fracture interval can take good advantage of the fracture interaction so as to reduce the horizontal differential principal stress. However, exceeded fracture interaction may raise the fracture pressure. So the effect must be controlled by optimizing the fracture interval. To optimize the fracture interval, the results can be used to instruct the application of multi-stage fracture stimulation.

• Periodical: Applied Mechanics and Materials (Volumes 513-517)
• Pages: 4012-4015
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.513-517.4012
• Online since: February 2014
• Authors: Feng Shen*, Xi Yu Chen, Zhi Huang, Hong Jun Qiao
• Keywords: Fracture Pressure, Horizontal Well Fracturing, Induced Stress, Ordos Basin

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