Determination of Loss Circulation Zones by Using Real-Time Temperature Logging While Drilling Petroleum Wells – Case Studies
The acquisition of temperature logs in drilling and evaluation operations is commonly applied as a support tool to determine rock formation geothermal gradient, environmental corrections used in electrical logs and to design cement jobs, among other applications. This article focuses on presenting the use of these temperature logs, with data acquired by the APWD (Annular Pressure While Drilling) tool, to identify potential loss circulation intervals during wellbore drilling, since the sensors are closely attached to the drill bit. Under normal wellbore drilling conditions, temperature increases as the well deepens, depending on variations of the geothermal gradient and on physical properties of the rock-fluid system. Changes in this behavior, which are emphasized by the signature of temperature logs, in association with zones of circulation losses, allowed the identification of these intervals. The magnitude of circulation loss is also reflected in the temperature log response, which is likely to be more affected where severe losses are detected. Determining these intervals is essential to better control wellbore conditions as this information helps it directing strategies to combat severe circulation losses, thus ensuring well safety and reductions in operational costs.
AAPG Datapages/Search and Discovery Article #90332 © 2018 AAPG International Conference and Exhibition, Cape Town, South Africa, November 4-11, 2018