Triangle USA Petroleum Corporation is a Denver-based independent oil and gas exploration and production company and a subsidiary of Triangle Petroleum Corporation. The company focuses on developing unconventional shale resources in the Williston Basin across North Dakota and Montana. As of 2016, it held approximately 100,000 net acres, operated 144 producing wells, and reported proved reserves of 47,707 Mboe. The firm employs 59 people and utilizes midstream services for crude oil, natural gas, and water gathering.