TECHNICAL ANALYSIS OF XIANG 1 WELL DRILLED THROUGH THE HALITE FORMATION

XING 1 well in Tarim Basin is a deep exploration well. While drilling through the Permo-Caboniferous formation,a composite salt formation was encounted from 5 166m to 5 331.38m,and then lost circulation and drill pipe sticking occured many times and the down hole condition was very complex. Drilling fluid types and properties were optimized,by analyalng the creep properties of the composite salt formation. Formation breakdown pressure was thought to be rather low (1.61~1.65g/cm3 ),so only low density drilling fluid and undersaturated salt-water drilling fluid system (chlorion content of 180 000~185 000ppm) could be used to control the creep rate of the salt formation. The result proved to be successful. This paper recommened the experience and lessons got from drilling XING 1 well through the composite salt formation.