Burgos is the first major unassociated gas basin in Mexico. It covers an area of 50,000 km2 and contains complex, sandstone reservoirs, which are highly compartmentalized and made up of several small, independent blocks characterized by low permeability. This basin is considered a tight-gas reservoir. Sustaining a high production level in this area requires a large number of wells to be drilled and hydraulically fracture stimulated. Historically, the initial well productivity is high, but declines quickly. This phenomenon seems as if it could be associated with the loss of fracture conductivity shortly after the well is put on production.
Proppants that are factory coated with a partially cured resin, generally referred to as resin coated proppants (RCPs) have been used in the industry to reduce proppant flowback and to improve fracture conductivity. A more recent methodology is to coat proppants on location using liquid-resin systems (LRSs). This method uses a specific type of hydrophobic material to resin-coat proppants, and has often been used in the industry specifically to prevent post-frac proppant flowback. The proppant is coated on-the-fly on location with the LRS material. This technology has also proven to both initially increase and also to better sustain fracture conductivity over time. The use of liquid resins for proppant coating in the Burgos basin to enhance and maintain conductivity in several fields has shown to lead to better well performance than when using the factory-coated RCPs.
Production data from a LSR treated well after almost two years of production is presented and compared to a well with similar petrophysical characteristics completed in the same productive block in the same formation using the same volume of a RCP type proppant.
The similar conditions initially present in these wells will forcefully support the superior behavior of LRSs when compared to conventional RCPs when placed using identical treatment designs.