The lithostratigraphy, microlithofacies, and conodonts are described in a key section of the Wahoo Limestone (Middle Carboniferous); this unit forms a hydrocarbon reservoir at Prudhoe Bay. The Wahoo was deposited in a range of environments on the inner part of a high-energy carbonate ramp. Microfacies and conodont biofacies used together refine paleoenvironmental interpretations. Only 24 conodont species distributed among 14 genera were recognized in a section that spans about 10 million years. Significant conodont collections from the Wahoo across the Northeast Brooks Range are described in an appendix.