Geology and conceptual model of the Domuyo geothermal area, northern Patagonia, Argentina
Por:
Silva-Fragoso, Argelia, Ferrari, Luca, Norini, Gianluca, Orozco-Esquivel, Teresa, Corbo-Camargo, Fernando, Pablo Bernal, Juan, Castro, Cesar, Arrubarrena-Moreno, Manuel
Publicada:
1 dic 2021
Resumen:
The western slope of Cerro Domuyo in northern Patagonia is characterized
by thermal springs with boiling waters, Quaternary silicic domes, and
pyroclastic deposits that suggest the existence of a geothermal
reservoir. According to geochemical studies, the reservoir may have a
temperature of 220 degrees C and one of the largest advective heat
fluxes reported for a continental volcanic center. In this paper, we
propose a more refined conceptual model for the Domuyo geothermal area,
based on a geological survey supported by U-Pb, U-Th, and Ar-Ar
geochronology and by magnetotelluric and gravity surveys. Our study
indicates that the Domuyo Volcanic Complex (DVC) is a Middle Pleistocene
dome complex overlying middle Miocene to Pliocene volcanic sequences,
which in turn cover: 1) the Jurassic-Early Cretaceous Neuquen marine
sedimentary succession, 2) silicic ignimbrites dated at similar to
186.7Ma, and 3) the Paleozoicmetamorphic basement intruded by similar to
288 Ma granite bodies. The volcanic cycle in the DVC is distinctly
bimodal, characterized by the emplacement of massive silicic domes and
less voluminous olivine basalts on its southern slope. A major collapse
of the central dome at similar to 600 ka produced a voluminous (19.4
km(3) and 133 km(2)) block-and-ash flow, and associated pyroclastic
flows, that filled a valley to the southwest at distances up to similar
to 30 km fromCerro Domuyo summit. This was followed by a period of
intense effusive activity that formed the Cerro Guitarra, Cerro Las
Pampas, Cerro Domo, and Cerro Covunco silicic domes. The last twodomes
are the youngest and largest edifices, dated at 0.50Ma (Ar-Ar age) and
0.25Ma (U-Th age). Pre-Cenozoic successions were affected by N-S reverse
and thrust faults that were later displaced by an ENE-WSW-trending
transtensional belt. The basement rocks at the northern termination of
the Cordillera del Viento anticlinorium were also displaced towards the
east-northeast by this belt, which is observed NNW of Cerro Domuyo. The
DVC was emplaced within this zone of crustal weakness. The integration
of geologic observations with magnetotelluric and gravity data, allowed
us to develop an updated conceptual model of the geothermal system. The
geothermal reservoir is inferred at a depth of less than 2 km within
pre-Pliocene fractured rocks, bounded by similar to WSW-ENE trending
faults and sealed by the pyroclastic deposits and rhyolitic lavas of the
DVC. The location of most thermal springs is not directly controlled by
faults. Instead, flows emerge at the contact between the fractured and
faulted basement and the caprock. (C) 2021 Elsevier B.V. All rights
reserved.
Filiaciones:
Silva-Fragoso, Argelia:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Posgrad Ciencias Tierra, Campus Juriquilla,Blvd Juriquilla 3001, Queretaro 76230, Mexico
Ferrari, Luca:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Campus Juriquilla,Blvd Juriquilla 3001, Queretaro 76230, Mexico
Norini, Gianluca:
CNR, Area Ric CNR ARM3, Ist Geol Ambientale & Geoingn, Via Roberto Cozzi 53, I-20125 Milan, Italy
Orozco-Esquivel, Teresa:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Campus Juriquilla,Blvd Juriquilla 3001, Queretaro 76230, Mexico
Corbo-Camargo, Fernando:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Campus Juriquilla,Blvd Juriquilla 3001, Queretaro 76230, Mexico
Pablo Bernal, Juan:
Univ Nacl Autonoma Mexico, Ctr Geociencias, Campus Juriquilla,Blvd Juriquilla 3001, Queretaro 76230, Mexico
Castro, Cesar:
Goethe Univ Frankfurt, Inst Geowissensch, Altenhoeferallee 1, D-60438 Frankfurt, Germany
Arrubarrena-Moreno, Manuel:
Waldo Fresnos 7027, Zapopan 45010, Jalisco, Mexico
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