METHODS FOR MINIMIZING FLUID LOSS TO AND DETERMINING THE LOCATIONS OF LOST CIRCULATION ZONES

摘要

A method for determining a location of a lost circulation zone in awellbore having a first wellbore fluid therein that includes allowing loss ofthefirst wellbore fluid to the lost circulation zone to stabilize; adding avolume of asecond wellbore fluid having a density less than the first wellbore fluid tothewellbore on top of the first wellbore fluid to a predetermined wellbore depth;determiningan average density of the combined first wellbore fluid and second wellborefluid; mixing the first wellbore fluid and the second wellbore fluid together;pumping a volume of a third wellbore fluid having a density greater theaveragedensity of the combined first and second wellbore fluid into the wellborebottomuntil fluid loss occurs; and determining the location of the lost circulationzone isdisclosed.