Well completion practices in high-temperature, high-pressure carbonates are challenging especially for long lateral horizontal wells intended for fracturing applications. An integrated approach involving intervention and fracturing design and reliable post-fracturing flow measurements is very critical to optimize the well performance.
After initial intervention complexities due to wellbore accessibility in a 6,250-ft cemented lateral initially planned with 13 fracturing stages resulting in the loss of many operational days, a revamped engineering workflow was planned for Well-A. As a first step, Coiled Tubing (CT) was used for abrasive jetting perforations, cleanout, and acid squeeze functionalities with a novel bottomhole assembly (BHA). The BHA was equipped with a real-time telemetry to optimize intervention to a single run. Having real-time bottomhole parameters helped in perforating the desired zones accurately and enhanced the injectivity by creating cleaner perforation tunnels.
Stages were reduced to five with an optimized perforation design based on rock typing approach, and short clusters were designed to divert the fracture fluids effectively using multimodal particulate diversion. Each fracturing stage was isolated with a mechanical plug. A novel high-frequency pressure monitoring technique that analyzes fluid entry points from water hammers was utilized during the fracturing treatments to analyze on-the-fly diversion efficiency and optimize further treatments.
A multiphase flowmeter was utilized to enhance milling and flowback to minimize losses and manage the choke schedule based on actual well performance leading to better fracture cleanup and recovery. The production performance of Well-A was compared with two offset horizontal wells drilled azimuthally parallel, intersecting the same carbonate sublayer. The post-fracturing absolute production enhancement analysis showed 11 to 15% improvement, and productivity index (PI) improvement was 40 to 63% when normalized by stage count. The effective integration of multiple technologies was applied successfully on the candidate well, yielding enhanced operational efficiency with optimized production performance.