STUDY AND APPLICATION OF WELLBORE STABILITY FOR THE SANDSTONE LAYER IN THE SOUTH CHINA SEA
Put text here. The problems such as borehole collapse, leakage occurred frequently in directional drilling in sandstone reservoir of a certain block in theSouth China Sea. Relevant research reveal that due to the characteristics of Ingh porosity, high permeability, weak cementation and low strength, the sandstone reservoirs are subject to deformation under the effects of earth stress. It is the dominant of the wellbore instability. And practices demonstrate that it is an effectual means to keep wellbore stability through pressure come from mud, the key to prevent the instability of this block is proper drilling fluid density.This paper Applied structural gsological analysts to study the relative magnitude and appromate azimuth of the area firstly, then use wellbore breakout method to determine the orientation of the maximal earth stress. Analysis directional well circumferential stress distribution law base on mechanics mechanism and then established hole stability mechanical model. Confirm the intensive parameter and elastic parameter of the rock from laboratory experiment, earth stress and pore pressure, calculate and analysis the caving pressure and fracture pressure distribution law with deviation and azimuth. The conclusion is that under certain azimuth the e-quivalent mud density of caving pressure should increase with the increase of deviation; along direction of the minimal earth stress the fracture pressure should increase with the increase of deviation, while decrease with the increase of deviation along direction of the maximal earth stress, at the same time give the proper drilling fluid density in the horizontal section and concluded the optimum drilling azimuth is along the direction of the minimal earth stress.
Lou Yishan Li Zhonghui Xing Xuesong
Yangtz University Jingzhou,Hubei,China Yangiz University Jingzhou,Hubei,China CNOOC Beijing,China
国际会议
The 3rd World Conference on Safety of Oil and Gas Industry(第三届世界石油天然气工业安全会议 WCOGI 2010)
北京
英文
623-627
2010-09-27（万方平台首次上网日期，不代表论文的发表时间）