Operator successfully deploys four-zone multizone completion

Overview

A major operator in the Gulf of Mexico Lower Tertiary selected the XSTMZ™ Xtreme single-trip multizone system to complete multiple reservoirs with high pressure differentials. Due to reservoir pressure uncertainty, the four-zone multizone completion, originally configured as a single-trip installation, was ultimately installed in two trips. 

Challenges

Significant pressure differentials between zones necessitated a reconfigured design that allowed for a two × two-zone stacked XSTMZ system installation. This configuration allows for commingled production of all zones simultaneously. 

Solution

The XSTMZ system was designed for ultra-deepwater offshore completions. It evolved from the highly reliable, field-proven ESTMZ™ enhanced single-trip multizone system, which features a system rating of 3,750,000 pounds of proppant with a treating rate of 45 bbl/min. Fully rated to 15,000-psi working pressure, the XSTMZ system provides higher pump rate and proppant volume capability, which is crucial for managing and effectively developing depleted reservors in the  Lower Tertiary. 

Results

The XSTMZ system was deployed and all packers were set simultaneously. This  approach served two critical purposes: mitigate hydrostatic losses and reduce costs related to installation time. After setting the packers and displacing to completion fluid, the lower two-zone section was treated without tripping the work string.

Following the successful completion of the lower zones, the completion fluid was displaced to a higher-density fluid, the upper two zones were perforated, and a cleanout trip was performed. The upper two-zone XSTMZ system was then installed, and the upper two zones were treated as designed, without tripping the work string.

The proven strength, reliability, and innovative design of the XSTMZ system is crucial to our customer's continued deepwater and ultra-deepwater successes. The single-trip multizone capabilities with proven reliability represent a step change in the commercial viability of many such fields, helping operators maximize asset value.