First Time Application in Mexico's Burgos Basin of a New Technology Multi tageCompletion Process A Successful Case History

摘要

The Burgos Basin, located in Northern Mexico, is consideredby PEMEX to be one of Mexico's major natural gas reserves,and contributes a large portion of the country's current gasproduction. The basin's gas production comes from a series ofsandstone intervals, which are primarily characterized as verylow permeability. Consequently, the only way to obtainoptimum production rates is using hydraulic fracturingtechniques.Given that all the wells of the basin offer multiple potentialproductive zones, PEMEX was driven to look for alternativemethods and technologies, focusing their efforts on finding themost cost effective completion processes while maximizingthe production and returns in the field development.For years, the conventional completion process used byPEMEX has been PFFP (perforate-fracturing-flowing-plugging),then moving up hole to the next interval andrepeating the process. This process was strongly debatedinternally for quite some time due to considerable concerns offormation damage caused by fracturing fluids remaining information for extended periods of time prior to beingrecovered. Thus the focus became to modify and optimizeeach step of PFFP in order to reduce these concerns and theirimpact on the well's production.In 2003, a fairly new technology in multi-stage treatmentcompletion process was used. This technique, known as'External Casing Perforating' allowed PEMEX to perforateand isolate individual zones in as little as minutes betweenstages. As many as 5 zones have been completed within a 30hour period. The time from completion to production has beenreduced from days to hours.This paper will describe the implementation of this techniquein the Cuitlahuac Field, Burgos basin. Most importantly, thecase history is substantiated by a comparison with offset wells.The analysis includes the completion processes used, early and normalized gas production and an economical analysis madeusing both the conventional and the multi-stage processes. Inconclusion, the Production Company's perspective aboutimplementing this technology in a massive operation will alsobe presented.