Methane emissions from non-producing oil and gas wells in Argentina

Non-producing oil and gas wells are a poorly quantified source of anthropogenic methane emissions worldwide, posing a significant risk to the environment and contributing to climate change. In Argentina, a country with a long history of oil and gas production, methane emissions from non-producing wells remain largely uncharacterized. Here, we combine a national well database analysis with ground-based methane measurements to assess emissions from non-producing oil and gas wells across Argentina. By analyzing well databases from the government, we found 85,260 wells in Argentina, of which 53,292 (62%) are non-producing, with the largest number of wells in the provinces of Santa Cruz, Chubut and Neuquén. We analyze key well attributes, including well depth, well type (e.g., oil and gas), location, well age and well abandonment date. These attributes are essential to perform a spatial analysis and identify the regions in Argentina that should be prioritized for field measurements.

We conducted ground-based methane flow rates measurements at 75 non-producing oil and gas wells in Chubut province. Unplugged wells exhibited the highest emissions, with a maximum measured methane flow rate of 41g/h. We further analyzed the influence of categorical well attributes, such as operator, well status, plugging status, well type, and lift system on measured methane emissions, identifying attributes associated with higher or lower emission rates.

Using the field measurement results combined with the national well database, we provide an estimate of methane emissions from non-producing oil and gas wells in Argentina. Overall, our findings contribute to improving the characterization of existing non-producing oil and gas wells, to including methane emission estimates in Argentina’s national greenhouse gas inventory, and to identifying the regions that should be prioritized for continued monitoring of methane emissions.