Lucas W. Bazan, Bazan Consulting, Inc., Michael G. Lattibeaudiere, Rosetta
Resources Inc., and Terry T. Palisch, CARBO Ceramics
Multiple stage hydraulic fracturing is a key technology driving the development
of unconventional resources in North America. This technique began in the
Barnett shale and its application has opened the door for the successful
development of nearly every shale play in the world, including the Eagle Ford
shale. Given the relatively new application of this technique, and the number
of fracture treatments completed, initial fracture treatment designs in a given
play are often transferred from other North American shale plays to serve as
baseline treatments. Given the rapid pace of development in a new play, as well
as the desire to get to a standardized completion program, many operators
continue to use these baseline designs and fail to evaluate current designs to
develop more optimal treatments.
This paper will discuss the successful evolution of hydraulic fracture designs
in the Eagle Ford shale from one operator’s perspective. It will detail the
development from the traditional low conductivity slick water fracture
treatments used initially in the play, to the use of higher conductivity hybrid
fracture designs. In addition to detailing the theory and workflow of these
design changes, this paper will also evaluate production data from multiple
wells and evaluate production results for the hydraulic fracture designs.
Discussion of enhanced conductivity will be presented along with the economic
benefit of these changes.
Those working the Eagle Ford shale can directly apply the principles presented
in this paper to enhance the productivity and economics of their completions.
In addition, engineers working other resource developments can use the
principles from this paper to compare their current fracture design methodology
and develop best practice approaches for hydraulic fracture design optimization
in their respective plays.
Unconventional resources require fracture stimulation to achieve hydrocarbon
production at economic rates, and advancements in hydraulic fracturing
techniques and horizontal drilling in the past fifteen years have greatly aided
in the exploitation of these formations. Multiple stages and multiple clusters
per stage along the horizontal wellbore are routinely used to create multiple
transverse fractures which influence both initial production (IP) rate and
decline, and create large contacted reservoir volumes (CRV). The use of these
hydraulic fracturing and completion technologies, along with favorable market
conditions of natural gas liquids, has made field development economic for
Eagle Ford shale. Operators typically desire to identify a standardized
completion design as soon as possible. Given the relatively new application of
these hydraulic fracture techniques, treatment designs in the Eagle Ford shale
often originate from designs in other North American shale plays. Given the
rapid pace of development in the Eagle Ford shale, many operators continue to
use these baseline designs and fail to develop and evaluate more rigorous
engineering based treatments and evaluations.
The Eagle Ford shale play has had significant growth since 2009, with strong
well performance in the condensate window. The gas, condensate and oil
production from January – November 2011 was 221 Bcf, 18.7 MMbbl and 21.8 MMbbl
respectively (Figure 1) [Tx RRC]. Horizontal drilling activity continues to
grow throughout the field, with total rig count exceeding 200 rigs as of
February 2012 (Figure 2).