Recently both EOG Resources and Carrizo Oil & Gas announced new down-spacing programs designed to maximize exposure to the lower Eagle Ford shale. In their latest report, Carrizo announced that they are testing a “Stagger Stack” with spacing as low as 165′ between wells. Similarly EOG has announced a “W” drilling pattern which also involves staggered wells higher or lower in the formation between laterals of the same depth. EOG’s CEO William Thomas described their Eagle Ford Shale down-spacing plans recently:
“The W patterns; we will do multiple pilots, patterns, on that and it really will apply to the bulk of our Eagle Ford acreage. What we are doing is we are bringing the wells in. We have been drilling wells anywhere from 300′ to 500′ apart in our typical patterns. But we are bringing those closer and we will be doing that at various spacing, closer than 300 feet to 500 feet. And it really will vary a bit on the spacing, depending on the area. But the general concept of picking out multiple targets within the Lower Eagle Ford using these advanced techniques to identify the best rock will be applicable across the bulk of our acreage.”
Below is an illustration of Carrizo’s down-spacing test in the Western Eagle Ford Shale.
Last year Pioneer Natural Resources also announced a staggered spacing program to target both the upper and lower Eagle Ford Shale, prospective to approximately 25% of their acreage. EOG and Carrizo seem to be applying a similar approach to areas prospective to both upper and lower, as well as lower EFS only.
It will be interesting to see how much interference to adjacent wells is a factor as well as how the new “Stagger Stack” and “W” pattern down-spacing model will affect overall well EUR numbers. Also one wonders if EOG Resources and Carrizo Oil & Gas plan on increasing overall Eagle Ford Shale reserve numbers in the near future as a result of these downspacing programs.