Creep Property Experimental Research of Offshore Unconsolidated Sand Reservoir

Abstract:

Unconsolidated sandstone is a kind of formation with low strength and large deformation property. Deeper unconsolidated sand formations have larger geostress and perform the plastic and rheological characteristics. After the borehole has been drilled into, this kind of sandstone will creep, which will cause some problems such as pipe stuck and casing deformation failure etc. Therefore, creep parameters of unconsolidated sandstone are critical for designing drilling fluid density and choosing casing material. Through indoor experiments, creep data of unconsolidated sandstone from Zhujiang group of X oil field in the west of South China Sea was get. The experiments results indicate that creep law of this sandstone conforms to Nishihara’s model, and the creep parameters were calculated based on experiments data. According to Nishihara’s model, using numerical simulation method, this paper analyzes the relationship of sandstone creep shrinkage rate with time of Zhujiang group reservoir sandstone and determines the drilling fluid density that ensures the safety of horizontal wells drilling, which has guiding significance for well design and drilling.

• Periodical: Applied Mechanics and Materials (Volumes 638-640)
• Pages: 422-426
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.638-640.422
• Online since: September 2014
• Authors: Ji Wen Liang*, Chuan Shi Lu, Chong Zhang, Yi Long Xu, Chao Zhang, Jian Guo Chen
• Keywords: Creep Rate, Drilling Fluid Density, Safe Drilling, Unconsolidated Sandstone

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