Geo-pedological contribution to the reconstruction of Holocene activity of Chaitén volcano (Patagonia, Chile)

Post–glacial tephrochronology record off the Chilean continental margin (∼41° S)

“…T7/100 is the oldest cryptotephra that occurs in the Early Holocene, which has an estimated age of ~9.6 cal ka BP (1σ: 9.7-9.5). Evidence on land for Michinmahuida activity around this time is presented by Casati et al (2019), who dated a deposit attributed to Michinmahuida at ~9.2 cal ka BP (1σ: 9.3-9.2), very similar to the estimated calendar age for T7/100 (Figure 6). Amigo et al (2013) identify one scoria deposit (5 th scoria in the Mallines section) from Michinmahuida and bracket this event between ~7.6 and 10.3 cal ka BP.…”

“…have a geochemical composition corresponding to Michinmahuida. A comparison of the element measurement for Pumalín-4 (Pum 4-7), the deposit (P16-5Csm) identified byCasati et al (2019) and the 5 th scoria, display La/Yb versus Zr/Nb values close to those know for Michinmahuida and to T7/100 (Figure7f). 5.1.4.5 T6/98 and T8/100 T6/98 and T8/100 correspond to the only visible tephras in cores MD07-3098 and MD07-3100, respectively.…”

“…Comparison of specific crytotephras belonging to Group 1 displaying a Michinmahuida signature with potential correlatives on land.In all cases all the available information from Michinmahuida is plotted as cyan symbols in the background(Alloway et al, 2017a;Amigo et al, 2013;López-Escobar et al, 1993;Naranjo and Stern, 2004) and specific correlatives are indicated in the legend. LTT-14, LTT-15, LTT-18 and LTT-20(Moreno et al, 2014), MIC1( Amigo et al, 2013;Naranjo and Stern, 2004), Pum 2-11 and Pum 4-7(Alloway et al, 2017b), P17-4CBd and P16-5Csm(Casati et al, 2019), 5th scoria(Amigo et al, 2013), Lepué(Alloway et al, 2017a;Amigo et al, 2013), Unknown correspond to products…”