A review of Devonian–Carboniferous magmatism in the central region of Argentina, pre-Andean margin of SW Gondwana

Palaeozoic – Early Mesozoic geological history of the Antarctic Peninsula and correlations with Patagonia: Kinematic reconstructions of the proto-Pacific margin of Gondwana

“…2), although at least part of the detrital zircon record indicates a more significant localised source region for the northern Antarctic Peninsula. Late Devonian magmatism in southern Patagonia developed in two contemporaneous belts, possibly reflecting double subduction along both a continental margin and island arc setting (Hervé et al, 2013) or a function of subduction slab dynamics (Dahlquist et al, 2021), which is favoured here based on our GPlates kinematic reconstructions. The evolution of the Devonian-Carboniferous magmatism between 27 • and 35 • S is best explained by a segmented tectonic subduction and switch-off and switch-on geodynamic model (push-pull tectonics), including the transition from flatslab to roll-back subduction involving delamination of the upper plate and break-off of the oceanic slab (Dahlquist et al, 2021).…”

“…Late Devonian magmatism in southern Patagonia developed in two contemporaneous belts, possibly reflecting double subduction along both a continental margin and island arc setting (Hervé et al, 2013) or a function of subduction slab dynamics (Dahlquist et al, 2021), which is favoured here based on our GPlates kinematic reconstructions. The evolution of the Devonian-Carboniferous magmatism between 27 • and 35 • S is best explained by a segmented tectonic subduction and switch-off and switch-on geodynamic model (push-pull tectonics), including the transition from flatslab to roll-back subduction involving delamination of the upper plate and break-off of the oceanic slab (Dahlquist et al, 2021). Ramos (2008) suggested that two coeval magmatic arcs; a western belt broadly parallel to the present continental margin that was active from the Late Silurian to the mid-Carboniferous and a southern magmatic arc that eventually led to the collision of Patagonia with southwest Gondwana.…”

“…This paired subduction tectonic setting was interpreted to be active throughout the mid-Devonian, with island arc magmatism recorded in the interval 385-360 Ma and continental margin arc magmatism (2002) continuous from at least 400-350 Ma (Hervé et al, 2016). Dahlquist et al (2021) examined occurrences of Devonian -Carboniferous magmatism from the Sierras Pampeanas and Frontal Cordillera region (Fig. 6) and identified an almost continuous magmatic episode from 395 to 320 Ma, but with significant compositional variations both spatially and chronologically.…”

“…393-366 Ma) foreland magmatism was attributed to resubduction >800 km inland from the trench. In this configuration, Devonian arc magmatism was absent, but voluminous foreland magmatism developed, including small-scale high silica-adakite mostly derived by the partial melting of the resubducted oceanic slab (Dahlquist et al, 2021).…”

Silurian inverted Barrovian-type metamorphism in the Western Sierras Pampeanas (Argentina): a case of top to bottom heating?

“…The term Famatinian orogeny was coined by Aceñolaza & Toselli (1976) and is retained here because it is rooted in the geological literature (e.g. Astini & Dávila, 2004; Ramos, 2018; Rapela et al 2018; Weinberg et al 2018; Otamendi et al 2020; Dahlquist et al 2021; Alasino et al 2022). However, the timespan of the Famatinian orogeny has been progressively restricted (e.g.…”