Aerial photos of drilling at Pawnee grassland

When geologist Evan Anderman began taking photographs full-time 10 years ago, he was drawn to disrupted landscapes. These aerial images show oil and gas development in the Pawnee National Grassland in northeastern Colorado. The geology was intriguing, he says, particularly its alteration by the oil companies. “Look at the layers in the photographs,” he says: “The geology forms the lowest layer, with cattle grazing draped on top of that, and both of those in turn disrupted by drilling.” The landscape continues to shift with ebbs and flows of energy development. On Dec. 2, the U.S. Forest Service proposed an updated plan to keep 100,000 still-unleased acres in the area open to leasing, while requiring companies to drill horizontally from private land to avoid surface disturbance. The grassland currently has 62 active wells, with 234 more predicted for the long term, which tap the Niobrara shale. —Tay Wiles, online editor of High Country News.