Tracey J. Mercier Phuong A. Le Andrea D. Cicero Sarah E. Gelman Jane S. Hearon Benjamin G. Johnson Jenny H. Lagesse Heidi M. Leathers-Miller Christopher J. Schenk 2026 <p class="MsoNormal">Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean conventional resources of 208 million barrels of oil and 4.1 trillion cubic feet of gas in the greater Carpathian area.</p> application/pdf 10.3133/fs20263060 en U.S. Geological Survey Assessment of undiscovered conventional oil and gas resources in the Greater Carpathian area, 2024 reports