Key Techniques for Deep Well Drilling Optimization in the Block Matambo,Colombia

The formation depth of the Block Matambo in Columbia is around 5 000.00 m.Situated in mountainous terrain,it has complex surface conditions with a large dip angle,multiple pressure systems,high in-situ stresses,frequent fault and fracture zones,multiple thick mudstone formations,massive gravel formations and abnormally high-pressure formations.Downhole problems like well collapse,drill pipe sticking,and circulation lost were frequently encountered in the drilling process in six well drillings resulting in slow drilling rate and long drilling cycle.In order to improve the oil and gas exploration and development benefits in this block,we conducted technical research from the aspects of casing program optimization,wellbore trajectory design and control,multi-parameter monitoring and analyzing while drilling,cementing technique optimization,drilling fluid system optimization,etc.by fully analyzing the geological conditions of this block and summarizing the experiences of previously drilled wells Based on the research,we developed key techniques in deep well drilling suitable for this block.Field tests have been conducted in the Well G10ST5 and it was drilled to the designed depth smoothly with wellbore quality and cementing quality up to design requirement.Compared with other six deep wells drilled within this block,the drilling cycle was reduced by 20.7 days and average ROP was increased from 3.00 m/h to 7.00 m/h,and loss time from downhole failure decreased from the original 15%-30% to 7%,and the comprehensive drilling cost was reduced by nearly 45%.The results of field tests illustrated that those key techniques in deep well drilling in the Block Matambo could meet the requirement of enhancing speed and efficiency in deep well drilling,and also provide a good analogy and reference points in the rapid drilling of complicated deep wells in similar formations.