Abstract:Ashele copper mine in Xinjiang Altay region is in typical altered water sensitive formation mainly with tuff, amphibolite, large stratigraphic dip and obvious rock anisotropy, borehole is easily deviated in drilling process. The frequent accidents of hole shrinkage, collapse, block falling and sticking restricted the selection of deviation prevention and correction technologies, which makes it difficult for the field drilling construction to meet the requirements of fast and economic geological prospecting. By the analysis on deviation prevention and correction technologies in the constructed water sensitive formation, a series of technical measures of deviation prevention and correction in water sensitive formation is presented to improve the quality of drilling hole.