The Choiyoi Silicic Large Igneous Province of Argentina and Chile and Its Possible Influence on Permian Environmental Degradation and Mass Extinction

Tracking voluminous Permian volcanism of the Choiyoi Province into central Antarctica

“…281-252 Ma; Fig. 6) and the mean age of all zircon from the three samples, 268 ± 1 Ma, is within uncertainty of a major peak in Choiyoi volcanic activity at 269-263 Ma (Rocha-Campos et al, 2011;Kimbrough et al, 2016). Distal tuffs from the Karoo Basin, South Africa, have a broad peak in zircon ages of ca.…”

“…1) is principally characterized by widespread Permian subduction-related andesitic to rhyolitic volcanic rocks (primarily ignimbrites) erupted over an area of ~1.7 Mkm 2 of Chile and Argentina, with an average thickness of 700 m emplaced between ca. 282 and 251 Ma with a major flare-up at 269-263 Ma (e.g., Rocha-Campos et al, 2011;Kimbrough et al, 2016;Spalletti and Limarino, 2017). The plutonic components of the Choiyoi are broadly defined as tonalitiesgranodiorites to granites emplaced between 286 and 247 Ma (e.g., Sato et al, 2015).…”

“…Definitive volume estimates for the Choiyoi Province, volcanic and plutonic, are lacking but there is broad consensus that the Choiyoi Province represents the largest silicic magmatic event in southwestern Gondwana (e.g., Rocha-Campos et al, 2011;Sato et al, 2015;Kimbrough et al, 2016;Spalletti and Limarino, 2017). The age of the Choiyoi Province (ca.…”

“…286-247 Ma) overlaps with the Permian-Triassic and End Guadalupian mass extinction events, carbon isotope excursions, and a shift from icehouse to greenhouse conditions associated with increases in atmospheric greenhouse gases (Spalletti and Limarino, 2017). For these reasons the Choiyoi Province has been proposed as a major source of volcanogenic greenhouse gases (e.g., CO 2 ) during volcanism and magmatism that heated organic-rich Paleozoic sedimentary rocks, releasing additional greenhouse gases and contributing to Permian global warming and environmental crises (Kimbrough et al, 2016;Spalletti and Limarino, 2017;Henry et al, 2009;Henry, 2013;Hermann et al, 2011;Luppo et al, 2018;Limarino et al, 2014).…”

“…1; Rocha-Campos et al, 2011;Sato et al, 2015;Castillo et al, 2016;Elliot et al, 2016Elliot et al, , 2017McKay et al, 2016). In South America, Permian arc volcanism resulted in exceptionally high volume silicic volcanism of the Choiyoi Province (estimated volume of ~1.3 Mkm 3 ) that may have contributed to global climate change, Permian mass extinctions and biotic crises (e.g., Henry et al, 2009;Hermann et al, 2011;Henry, 2013;Limarino et al, 2014;Kimbrough et al, 2016;Spalletti and Limarino, 2017;Luppo et al, 2018). Correctly correlating Permian volcanic deposits in southwestern Gondwana to the Choiyoi Province, therefore, is critical to determining the distribution and timing of one of the largest silicic provinces along the paleo-Pacific margin of Gondwana and its relationship to Permian global warming and environmental degradation.…”