Figure 1

Study areas in the Argentinian Patagonia. Data are plotted on SRTM topography¹⁸ displayed in shaded relief. (a) Neuquén basin area. Blue circles represent epicentres of seismic events scaled by local magnitude (ML) occurred in the period November 2015 to November 2020, from the Instituto Nacional de Prevención Sísmica (INPRES) catalog. The red dashed circle indicates the 15 km radius area analysed in Fig. 3a. Black triangles indicate the ___location of fracking wells (where unconventional hydrocarbons are extracted after slickwater injection), orange triangles indicate the ___location of conventional wells and green triangles indicate the ___location of wastewater injection wells (locations from the Argentine Energy Secretariat). Black lines indicate the main faults from¹⁹. The Global Centroid Moment Tensor (GCMT, www.globalcmt.org/) focal mechanism of the 07/03/2019 earthquake (ML 4.9, Mw 5) is shown. (b) Golfo de San Jorge area. Green triangles represent production wells. Black lines indicate the main faults²⁰. The red dashed circle indicates the 5 km radius area analysed in Fig. 7a. The Global Centroid Moment Tensor (GCMT) focal mechanism of the 17/10/2019 earthquake (ML 5, Mw 4.9) is shown. (c) Inset map showing the region of South America with the two study areas delineated in blue (Neuquén basin) and red (GSJ basin).