Early Production Decline Characteristics Main Controlling Factors and Development Insights for Horizontal Wells in the Wuping Block of Yanchang Oilfield

DOI: https://doi.org/10.62517/jes.202602123

Author(s)

Qiang Zang

Affiliation(s)

Karamay Vocational & Technical College, Xinjiang, China

Abstract

To address the issues of "rapid and complex production decline" observed in horizontal wells within the ultra-low permeability reservoirs of Yanchang Oilfield, this paper takes a typical well in the Wuping Block (Well Wuping-1) as a case study. By integrating production data analysis with multi-fracture numerical simulation, the early decline characteristics were systematically investigated. The results indicate that: 1) the early decline follows a harmonic decline model (R²>0.96), revealing a high initial decline rate post-fracturing. 2) Multi-fracture simulation demonstrates significant uneven production distribution, characterized by "shielding effects" and "dead oil zones" near the wellbore, with the main production contribution coming from fractures on both sides and distal fractures. 3) Comparison with the performance of adjacent wells clarifies that waterflooding effectiveness, water breakthrough risks, and capillary forces are key factors controlling the transition of decline patterns. Based on these findings, engineering recommendations for mitigating decline are proposed from three aspects: optimizing fracturing design, fine-tuning waterflooding management, and preventing water breakthrough. These insights provide guidance for efficient development of similar reservoirs.

Keywords

Horizontal Well; Production Decline; Harmonic Decline; Multi-Fracture Simulation; Shielding Effect; Water Breakthrough

References

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