The Sea That Made the Basin

Three hundred million years ago, a shallow inland sea spread across what is now West Texas and southeastern New Mexico. The sea teemed with marine life. Coral reefs built up along its margins. Fish and shellfish and microscopic organisms lived, died, and sank into the sediment over tens of millions of years. The sea retreated. The organic matter compressed. Heat and pressure transformed it over geologic time into the substance that, in the twentieth century, would make this stretch of desert one of the most consequential pieces of land in American history.

The Permian Basin takes its name from the Permian geologic period, the final interval of the Paleozoic era. It contains some of the thickest deposits of Permian-aged rock anywhere on Earth, accumulated during the collision of ancient North America with the landmass that would become South America and Africa. The basin stretches more than eighty-six thousand square miles across West Texas and southeastern New Mexico, roughly two hundred fifty miles wide and three hundred miles long.

For most of recorded history, the surface gave no indication of what lay beneath it. The landscape was flat, dry, and featureless to an extent that disoriented European explorers. Francisco Coronado crossed part of it in fifteen forty-one and described it as a place with no more landmarks than if we had been swallowed up by the sea. He meant this as a complaint. He had no way of knowing that the sea, in a sense, was exactly what lay beneath his boots.

By two thousand nineteen, the Permian Basin was producing an average of four point two million barrels of crude oil per day, more than any oil field in the United States and more than most countries in the world. The ancient sea floor had become the engine of the modern American economy, and the cities of Midland and Odessa sit on top of it.