The Eagle Ford Shale is Texas's second major shale play. It stretches across South Texas in a long crescent shape. The formation runs from the Mexican border in the southwest to East Texas in the northeast. It is about 50 miles wide and nearly 400 miles long. The Eagle Ford sits underneath some of the most active oil country in America.
What Is the Eagle Ford Shale?
The Eagle Ford is a rock layer that formed about 95 million years ago. At that time, a shallow sea covered much of what is now Texas. Sea creatures died and sank to the bottom. Over millions of years, the sediment built up, heated up, and turned into shale rock. The organic material from those sea creatures became oil and natural gas. That oil and gas is still trapped in the Eagle Ford today.
The word shale describes a rock made of compressed mud, clay, and silt. Shale is very dense. Oil doesn't flow through it easily on its own. That's why hydraulic fracturing — cracking the rock with high-pressure fluid — is needed to produce oil from shale formations.
What Does the Eagle Ford Produce?
The Eagle Ford produces three different hydrocarbons depending on where you are in the formation. Hydrocarbons are molecules made of hydrogen and carbon. Oil and natural gas are both hydrocarbons. Here is how the Eagle Ford breaks down by zone:
- Oil window — The southwestern part of the play produces mostly crude oil. This is the most valuable product. Counties like Webb, LaSalle, and Dimmit sit in this zone.
- Condensate window — The middle section produces natural gas condensate. Condensate is a very light liquid — almost like a very thin oil. It forms a clear or light yellow liquid at surface conditions.
- Dry gas window — The northeastern part of the play produces mostly dry natural gas. This is the least valuable zone for liquid production but still significant for gas output.
How Much Has It Produced?
The Eagle Ford shale boom started around 2008 and took off quickly. Production grew from almost nothing to over 1.7 million barrels per day at its peak in 2015. That peak made the Eagle Ford one of the fastest-growing oil plays in history. After 2015, production declined as oil prices fell and drilling slowed. It bottomed out around 2016 at about 1 million barrels per day. Since then it has stabilized. Today the Eagle Ford produces roughly 1.1 million barrels of oil per day, plus significant natural gas and condensate.
What Counties Are Most Active?
The most active counties for Eagle Ford drilling are:
- Karnes County — One of the highest per-well production rates in the play. Many of the best Eagle Ford wells ever drilled are in Karnes.
- DeWitt County — Another top-tier county in the oil window. Dense drilling activity.
- Gonzales County — Strong oil production and good well results.
- La Salle County — In the oil and condensate window. Very active area.
- Webb County — In the deep oil window near Laredo. Significant production.
How Deep Is the Eagle Ford?
Depth varies across the play. In the oil window, the Eagle Ford typically sits between 6,000 and 12,000 feet below the surface. In the gas window to the northeast, it can be shallower — around 4,000 to 6,000 feet. The thickness of the Eagle Ford also varies. It can be as thin as 50 feet or as thick as 300 feet, depending on location. Thicker sections generally hold more oil.
Who Operates in the Eagle Ford?
Major operators in the Eagle Ford include EOG Resources, ConocoPhillips, Marathon Oil, Devon Energy, and Murphy Oil. EOG was an early pioneer in the play and still holds large acreage. Smaller independent companies also have meaningful positions. The Texas Railroad Commission's records show every operator, every permit, and every well — going back to the very first Eagle Ford wells drilled in the late 2000s.
What Can Historical Data Tell You?
Scout tickets and production records from the Railroad Commission are invaluable in the Eagle Ford. Early wells in a new area often had poor results because drillers were still learning the best techniques. Later wells using better completions — longer horizontal laterals, more fracture stages — often performed far better. Understanding where the best wells are, and why, helps you evaluate any Eagle Ford prospect. ScoutTickets.io makes that historical data accessible and easy to understand.