Challenges and Successes in Horizontal Drilling Shallow 3D Unconventional Turbidite Reservoir,Mexico

摘要

Aggressive plans for exploiting vast oil resources within the Chicontepec basin(Mexico-Poza Rica)are currently underway.One of the most complex deposits in the world,this basin is qualified as an unconventional turbidite reservoir,and one of its characteristics is the existence of hydrocarbon resources in shallow regions.Horizontal wells within this basin are extended three-dimensional(3D)wells in parallel arrangement,suitable for termination techniques,such as simultaneous multi-fracturing. Commercially developing these resources requires the construction of wells that present major challenges.These challenges can be attributed to low depth,required dog leg severities close to 8°/30 m, 3D geometry necessary for construction and horizontal navigation uphill“boomerang”within the target unconsolidated sand formations(which are thin and unstable with mechanical hydraulic limitations), superficial limitation of space,the use of conventional drilling equipment,and required exhausting analysis. The successful exploitation of these wells was achieved with thorough planning simulation,detailed engineering analysis,and the selection of appropriate tools for each operational stage.Monitoring key factors during drilling was essential to helping prevent problems with uncompacted sands and gas migration. The use of advanced technology helped reduce deviation from the plan designed for the well and helped achieve a successful completion using a rotary steerable system(RSS),in some cases from the first casing, to prevent collapse and initiate the construction of the kickoff point(KOP).