0
Research Papers: Petroleum Engineering

Borehole Stability Analysis in Deepwater Shallow Sediments

[+] Author and Article Information
Yan Chuanliang

School of Petroleum Engineering,
China University of Petroleum, Huadong,
Qingdao 266580, China;
State Key Laboratory of Petroleum Resources and Prospecting,
China University of Petroleum,
Beijing 102249, China
e-mail: yanchuanliang@163.com

Deng Jingen, Li Xiaorong

State Key Laboratory of Petroleum Resources and Prospecting,
China University of Petroleum,
Beijing 102249, China

Lai Xiangdong

Drilling Engineering Technology Research Institute,
CNPC Chuanqing Drilling Engineering Co., Ltd.
Guanghan 618300, China

Feng Yongcun

The University of Texas at Austin,
Austin, TX 78741

1Corresponding author.

Contributed by the Petroleum Division of ASME for publication in the JOURNAL OF ENERGY RESOURCES TECHNOLOGY. Manuscript received April 23, 2013; final manuscript received April 12, 2014; published online July 9, 2014. Assoc. Editor: G. Robello Samuel.

J. Energy Resour. Technol 137(1), 012901 (Jul 09, 2014) (7 pages) Paper No: JERT-13-1136; doi: 10.1115/1.4027564 History: Received April 23, 2013; Revised April 12, 2014

Deepwater shallow sediment is less-consolidated, with a rock mechanical behavior similar to saturated soil. It is prone to borehole shrinkage and downhole leakage. Assume the deepwater shallow sediments are homogeneous, isotropic, and ideally elastoplastic materials, and formation around the borehole is divided into elastic and plastic zone. The theories of small deformation and large deformation are, respectively, adopted in the elastic and plastic zone. In the plastic zone, Mohr–Coulomb strength criterion is selected. The stress and deformation distributions in these two zones, and the radius of plastic zone are derived. The collapse pressure calculation formula of deepwater shallow sediments under the control of different shrinkage rates is obtained. With the introduction of excess pore pressure theory in soil mechanics, the distribution rule of excess pore pressure in these two zones is obtained. Combined with hydraulic fracturing theory, the fracture mechanism of shallow sediments is analyzed and the theoretical formula of fracture pressure is given. The calculation results are quite close to the practically measured results. So the reliability of the theory is confirmed.

FIGURES IN THIS ARTICLE
<>
Copyright © 2015 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

The mechanical model of a borehole

Grahic Jump Location
Fig. 2

Variation of borehole shrinkage rate with the borehole pressure

Grahic Jump Location
Fig. 3

Total stress around the borehole

Grahic Jump Location
Fig. 4

Excess pore pressure around the borehole

Grahic Jump Location
Fig. 5

Effective stress around the borehole

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In