Failure to manage and minimize lost circulation can greatly increase the cost of drilling and the risk of well abandonment.Many lost circulation remedial procedures are not working as planned because the locations of ...Failure to manage and minimize lost circulation can greatly increase the cost of drilling and the risk of well abandonment.Many lost circulation remedial procedures are not working as planned because the locations of loss zones are incorrectly estimated.The lack of this critical piece of information prevents treatments from being applied directly to the points of losses and, thus,resulting in low efficiency and extended NPT （non-productive time）. This paper presents an integrated method for identifying thelocations of loss zones with continuous temperature measurement data enabled by drilling microchip technology. A transient thermalmodel in predicting the temperature profiles in the wellbore and formation during mud loss is developed as a forward calculationprocedure of the loss zone mapping method. For a deep well with moderate to severe loss, there are significant changes in the mudcirculating temperature profiles as mud loss persists. Certain characteristics ofwellbore thermal behavior are evaluated and identifiedas good indicators of loss zones. Case studies are conducted to demonstrate the practical applications of the method in both onshoreand offshore drilling applications. The results from these case studies are important in setting cement plugs, applying expandabletubular systems, and spotting LCM （lost circulation material） pills. Additional uses of this method include identifying highlypermeable zones for reservoir or formation evaluation purposes. This method can be used as a routine monitoring process performedregularly without any interference of the drilling operations at the time.展开更多
文摘Failure to manage and minimize lost circulation can greatly increase the cost of drilling and the risk of well abandonment.Many lost circulation remedial procedures are not working as planned because the locations of loss zones are incorrectly estimated.The lack of this critical piece of information prevents treatments from being applied directly to the points of losses and, thus,resulting in low efficiency and extended NPT （non-productive time）. This paper presents an integrated method for identifying thelocations of loss zones with continuous temperature measurement data enabled by drilling microchip technology. A transient thermalmodel in predicting the temperature profiles in the wellbore and formation during mud loss is developed as a forward calculationprocedure of the loss zone mapping method. For a deep well with moderate to severe loss, there are significant changes in the mudcirculating temperature profiles as mud loss persists. Certain characteristics ofwellbore thermal behavior are evaluated and identifiedas good indicators of loss zones. Case studies are conducted to demonstrate the practical applications of the method in both onshoreand offshore drilling applications. The results from these case studies are important in setting cement plugs, applying expandabletubular systems, and spotting LCM （lost circulation material） pills. Additional uses of this method include identifying highlypermeable zones for reservoir or formation evaluation purposes. This method can be used as a routine monitoring process performedregularly without any interference of the drilling operations at the time.
