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The Las Minas area corresponds to an exhumed geothermal system considered a proxy for the deep part of the nearby Los Humeros active geothermal system. The stratigraphic succession is made up of: Palaeozoic-Miocene granitoids, a thick Jurassic- Cretaceous carbonate succession, Neogene lava flows and volcano-sedimentary deposits. Linked to a Miocene magma intrusion, marble and skarn rock-volumes developed by contact metamorphism and geothermal fluid flow. Faults are arranged in SW- and NNW-striking systems. These controlled the morphological evolution and favored Neogene-Quaternary dyke emplacement. Faulting gave rise to a tectonic depression where lacustrine sediments and pyroclastics deposited. Skarn rocks are mainly located at fault intersections and along pre-existing discontinuities, suggesting the role of bedding and/or fractures in channeling deep fluids. Results give inputs for exploration at depth of Los Humeros geothermal system.

This paper provides the first wide-area Interferometric Synthetic Aperture Radar (InSAR) survey of the whole eastern Trans-Mexican Volcanic Belt (42,200 km2). The aims are to identify ground deformation hotspots within major urbanized areas and rural valleys, establish baselines in geothermal exploration sites, and analyze deformation at geothermal exploitation sites and its relationship with energy production. The whole 2003−2010 ENVISAT C-band SAR archive available over the region was processed with the Small BAseline Subset (SBAS) InSAR method to retrieve over 840,000 coherent targets and estimate their ground displacement rates and time series. Land subsidence hotspots due to aquifer drawdown are found within the city of Puebla (up to −53 mm/year vertical rates, groundwater pumping for industrial use), Tlaxcala and Apizaco (−17 mm/year, industrial and public), the valley of Tecamachalco (−22 mm/year, agricultural), Tulancingo (−55 mm/year, public, industrial and agricultural), and in the eastern Mexico City metropolitan area (−44 mm/year, agricultural). The baseline for the Acoculco caldera complex shows widespread ground stability. Conversely, localized subsidence patterns of −5 to −10 mm/year exist around Las Derrumbadas and Cerro Pinto in the Serdán-Oriental basin, due to intense groundwater pumping for agriculture. A well-defined land subsidence area with −11 mm/year maximum rates is found at Los Humeros volcanic complex within Los Potreros collapse, correlating well with energy production infrastructure location and historical steam production rates. Field surveys carried out in Acoculco and Los Humeros in 2018 provide supporting evidence for the identification of hydrothermal manifestations, and understanding of the landscape and surface deformation patterns within the geothermal fields.

The geological map of the Tres Vírgenes Volcanic Complex (TVVC) Baja California Sur, México consists of three northeast-southwest aligned stratovolcanoes named from older to younger, El Viejo, El Azufre, and La Virgen. The map (scale 1:20,000) comprises an area of 856 km2 edited on an ArcMap data set. The map compiles previous studies combined with new mapping and stratigraphy supported by 5 new 230Th/U geochronology in zircons. The TVVC sits on top of Cretaceous granite, Cenozoic volcaniclastics, the Esperanza basalt (7.64 Ma), and the Aguajito ignimbrite (1.17 Ma). The TVVC commenced its activity around 300 ka by constructing El Viejo volcano, followed by El Azufre volcano (∼173–128 ka), la Virgen scoria cones (∼128–112 ka), and La Virgen stratovolcano (∼112–22 ka). The La Virgen volcano emplaced the La Virgen rhyolitic tephra (∼31 ka), and the Upper Andesite lavas (∼22 ka).