A Collaborative Approach to Optimizing Well Placement in A Highly Faulted Carbonate Field

The trajectories of the A1, A2 and A3 proposed development wells had been planned to avoid both faults and possible karsts features. A field development plan was implemented, including proposed well locations which were considered “safe” based on pre-drill seismic analysis. During the drilling operation of the A1 well encountered total losses 24m above the Top of Carbonate horizon, in the 12.25” section. These drilling losses of 100 barrel per hour triggered a subsequent well control event, causing the lower section of the well to be plugged and abandoned. The immediate efforts were taken in re-evaluating the drilling and seismic data post well control incident at Well A1 to optimize the well trajectories for the subsequent wells (Well A2 and Well A3). These efforts were taken to avoid hitting the similar fault zone. With detailed seismic attribute analysis and integrate the enhanced geologic understanding, well placement and well trajectories were further improved. The considerable time spent on the optimization efforts proved to be crucial as it prevented the recurrence of similar total losses event in Well A1 and resulted in safe and successful delivery of the remaining wells (Well A2 and Well A3).