Shale is 20% of U.S. oil production, and 80% of shale production comes from the Bakken and the Eagle Ford formations. But which formation should investors bet on?

Instead of arguing about formations, Aimee Duffy and Tyler Crowe decide to discuss a company that operates in both areas: EOG Resources (EOG 0.20%).

Despite its diversification, EOG ranks as the number three producer in the Bakken, right behind Bakken-centric Whiting Petroleum and Continental Resources.

EOG is a leader not only in production, but also in its operations. Moving Bakken crude via rail was pioneered by EOG Resources, allowing the company to move the product even before pipelines reach the formation. Valero, Tesoro, and Phillips 66 have subsequently announced their intention to buy rail cars.

Crowe is enthusiastic about EOG Resources, but Duffy is more reserved. Citing ConocoPhillips' lower-cost production, she encourages investors merely to keep an eye on EOG.