文摘
In recent years, with the advancement of exploitation for domestic tight gas reservoir, more and more attention has been paid to the borehole stability based on the quantitative prediction of ground stress. In this paper, related research has been made in a tight sandstone gas reservoir in eighth segment of Shihezi group (P1x) and first segment of Shanxi group (P1s) in Eastern Sulige of Inner Mongolia; limitation of application of Huang model in the area has been discussed on the basis of an in-depth analysis of the geological character according to the logging information, and a new optimized Newberry model has been obtained. By using this model, the horizontal ground stress of this region was quantitatively forecasted with minor error and the results prove that the Newberry model can perfectly fit the quantitative calculation of horizontal ground stress. In the meantime, according to borehole collapsed technique and the analysis of the trend of induced slot, the horizontal ground stress direction has been determined. The study shows that the maximum horizontal principal stress direction in eastern Sulige is close to east-west and the minimum horizontal principal stress direction is close to north-south. The elaborate research about the horizontal stress for the tight sandstone formation in eastern Sulige in this paper can meet the need of judgment of ground stress better in this area and it is of great significance to the safety of drilling of profitable reservoir in this area, reservoir fracturing and stimulating, and the safety of production in the subsequent process of development.
