( 1Instituto de Bio y Geociencias del NOA (CONICET-UNSa), Av. Bolivia 5150, A4400FVY Salta, Argentina

2CNR Istituto di Geologia Ambientale e Geoingegneria, sezione di Milano, Via Mario ( GEOLOGY OF THE TOCOMAR BASIN (PUNA PLATEAU, ARGENTINA) Bianco 9, 20131 Milan, Italy 3Università La Sapienza, Piazzale Aldo Moro, 5, 00185 Rome, Italy 1 1 2 1 3 1 4 3 5 1 4Università degli Studi di Roma Tre, Largo S. L. Murialdo 1, 00146 Rome, Italy Filipovich R. , Báez W. , Groppelli G. , Ahumada F. , Aldega L. , Becchio R. , Berardi G. , Bigi S. , Caricchi C. , Chiodi A. , 5Istituto Nazionale di Geofisica e Vulcanologia, 00143 Rome, Italy 4 5 4 6 2 4 7 1 2,4 6Università di Camerino, Piazza Cavour 19/f, 62032 Camerino (MC), Italy Corrado S. , De Astis G. , De Benedetti A.A. , Invernizzi C. , Norini G. , Soligo M. , Taviani S. , Viramonte J. and Giordano G. 7Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milan,

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Pozuelos Formation % % Crater rim 345 kV Power line 5a ê ê 1:20,000 Pastos Grandes 66°34'30"W 66°33'0"W 66°31'30"W 66°30'0"W Group LEGEND Cerro Aguas Calientes Caldera La Vega Formation : Thick heteropic epi-volcaniclastic succession made of pale green/light red alluvial terraced deposits of Unconsolidated deposits . Heterogeneous chaotic recent alluvial depostis covered by greyish eolian deposits (13). Present 9 poorly sorted conglomerates with volcanic sandstones and mudstones interbedded, and subordinate debris deposits Tajamar Ignimbrite. Homogeneous dacitic crystal-rich ignimbrites of red to pale pink colour. The thickness ranges from 570 m Geste Formation 12 13 b (a) alluvial and lacustrine deposits related to permanent and ephemeral water courses (14). subdivided into two members. The maximum outcropping thickness is about 90 m. (Middle Pleistocene). a 5 (intracaldera facies, 5a) up to less than 130 m (ouflow facies, 5b). Radiometric age 10.3 Ma .

Paleogene Upper member (9b): crudely stratified heterolithologic conglomerates widely varying in clast size and TOCOMAR BASIN UNITS composition in a greenish sandy-silty matrix. Locally interbedded with sandstones and gravelly sandstones with b Verde Ignimbrite. Pale green colour, pumice-rich ingnimbrite with variable grade of welding. The thickness ranges from 520 m 4 (a) Metamorphic and (Lower (?) - Upper Pleistocene) b minor mudstones and dark cross-bedded volcanic sandstones towards the top of the upper section. Internally a (intracaldera facies, 4a) to 80 m thick (outflow facies, 4b). Radiometric age 17.15 Ma . Ordovician Eastern Magmatic belt shows a basal fining-up section and an upper coarsening-up section. The maximum thickness exposed is about a 40 m. Pastos Grandes Group igneous basement La Cantera Formation . Terraced deposits of finely laminated and coarsely fibrous travertines interbedded with lithoclast 11 travertine. At the base, lenticular (1 m) alluvial deposits grades laterally into hardened heterometric conglomerates, formed by Lower member (9a) : terraced alluvial deposits made of crudely stratified, polimictic, matrix-supported, poorly Pozuelos Formation . It consists of a thick reddish/greyish continental succession of alluvial/fluvial deposits formed by (c) cobbles and pebbles of volcanic rocks (11a). The thickness is about 20 m. Radiometric ages 161±30 ka and 126±15 ka . sorted conglomerate with angular to subrounded, irregularly sized, clasts. Clasts mainly consists of granitoids 3 conglomerates, fine-grained sandstones, and siltstones with minor limestones and pyroclastic beds intercalated. Radiometric ai and volcanic cobbles and boulders, subordinate sedimentary pebbles and cobbles, in a hardened greyish sandy age 14.8 Ma(d). Countour interval 50 m a to granule-size matrix. The base of the sequence shows a 40 m structureless conglomerate interbedded with Alto Tocomar Formation . Complex volcanic succession subdivided into three members made of ignimbrites, pyroclastic Geste Formation. Red-purple to bright red color upward coarsening sequence formed mainly by fluvial and alluvial deposits. Project coordinators: Giordano G., Viramonte J.G. 10 surge, and fall deposits of rhyolitic composition. The maximum outcropping thickness is 120 m. Radiometric age 0.55±0.1 Ma (b) sandstone lenses (9a) that grades laterally and upward into a tabular thinly stratified fine to coarse sandstone Field survey coordinators: Baez W., Groppelli G. along with fine-grained homogeneous deposits (9ai). At the base prevails massive siltstone with lens of fine- to medium-grained sandstone interbedded grading upward into fine- to 2 coarse-grained sandstones, locally gravelly, intercalated with lens of pebble to cobble, clast-supported, conglomerates. The Geological survey : Filipovich R., Baez W., Becchio R., Ahumada F., Viramonte J.G., Aldega L., De Astis G., De Benedetti, El Puesto member (10c) : poorly-sorted pyroclastic well-stratified surge deposits. This unit crops out at Alto uppermost part of the succession shows coarser sediments made of thick beds of cobble to boulder, clast- to matrix-supported, Groppelli G., Giordano G. Tocomar distributed following a horseshoe geometry characterized by a well-developed stratification defined by San Jerónimo Formation : Blocky lava flows issued from the San Jerónimo scoria cone. These lava flows are shoshonitic 8 (b) conglomerates (Middle - Late Eocene). Structural survey: Bigi S., Caricchi C., Corrado S., Filipovich. R., Invernizzi C., Norini G., c an alternation of fines-depleted and lapilli-rich layers, with parallel to low-angle cross-stratified bedforms, and basaltic andesites. Radiometric age 0.78±0.1 Ma . Hydrogeology and Geochemistry of fluids : Chiodi A., Tassi F., Taviani S. bomb sags. Ordovician metamorphic and igneous basement U/Th age determinations: Berardi. G, Soligo M. PRE-TOCOMAR BASIN UNITS Quebrada Largadero member (10b) . At the base well-stratified pyroclastic surge deposit grades upward into a Editing and digital cartography: Filipovich R. Eastern magmatic belt . Porphyric and equigranular granites and granodiorites (1a) with scattered mylonites and mafic dike massive, often hardened, clast-supported fines-rich primary volcanic breccia. It is made of ~80% lava blocks and (Ordovician - Late Miocene) b a b 1 intrusion (1b) (Middle - Upper Ordovician). This work has been funded by the Italian Ministry of Foregn Affairs Progetto AR00197 di Grande Rilevanza “Sviluppo sostenibile lithic basement block in a yellowish ashy matrix. The maximum thickness is 45 m. Quevar Volcanic Complex . In the mapped area consists of a serie of higlhy fractured and disected andesitic lava flows on the 7 dei sistemi geotermici associati ai sistemi vulcanici della Puna nelle Province di Salta e Jujuy (2014-2016)”, directed by Giordano, El Apeadero member (10a) : pyroclastic flow deposits with thinly bedded pyroclastic-surge deposits with eastern caldera flank of Cerro Aguas Calientes Caldera G. and Viramonte J. G., and by PIO No. 3320140100015CO “Caracterización del Sistema Geotermal Tocomar y evaluación de References: (a) Petrinovic et al. (1999); (b) Aquater (1980); (c) This study; (d) Seggiaro et al. (2015) accretionary lapilli, and pyroclastic fall deposits composed of lapilli and coarse ash. Juvenile clasts made of su potencial como recurso energético no convencional sustentable para la Puna Argentina (2015-2017)” , financed by CONICET ai El Oculto Formation . Porphyric dacitic dike intrusions often hydrothermally altered and weathered. The dacitic intrusions have a pumice and dense glassy clasts. Due to pre-eruption topography the ignimbrite shows massive valley-pond and YPF S.A., Y-TEC 6 thicknesses ranging 1.5m to 15 m and an N60 main orientation probably related to the Punta del Viento domes of 11.8±0.4 Ma. DATA SOURCE: Information generated from satellite images interpretation and field field surveys. Geological mapping performed by the authors from 2014 to facies (10a) and thinner stratified veneer facies (10ai). The maximum thickness is greater than 45 m. 2016. Topographic base derived from © JAXA/METI ALOS PALSAR L1.0 2007. Accessed through ASF DAAC 11 November 2017. Coordinate system: WGS84