Relative and radiocarbon chronology of two former glaciers in the Chilean Lake District

Detailed seismic stratigraphy of Lago Puyehue: implications for the mode and timing of glacier retreat in the Chilean Lake District

“…Thus, the positions of the deltas described by Bentley (1997) indicate that the Puyehue glacier had retreated beyond these deposits and that again Rupanco meltwater was responsible for sediment deposition in the western sub‐basin of Lago Puyehue. The position of the depocentres at that time is best correlated with a possible advance of a Rupanco ice lobe south of Bahía Futacullín, as also proposed by Bentley (1997) based on onshore morphological and sedimentological observations.…”

“…Bentley, 1996, 1997) and the dates of the Puyehue glacier retreat based on the continuous sedimentary record of the PU‐II core. Both chronologies, the PU‐II core (Bertrand et al ., 2008) and the dated moraines (Bentley, 1997), have their flaws, but this timing conundrum does point towards some imperfections in the current deglaciation history of the Chilean Lake District. More in‐lake core studies should be performed to see if these age discrepancies also exist in other Chilean lakes.…”

“…Subsequently, the lake level must have risen to allow the creation of the delta deposits, currently exposed on land, which correlate well with the depocentres of unit V and which Bentley (1997) links to meltwater streams from the Rupanco glacier. Thus, the positions of the deltas described by Bentley (1997) indicate that the Puyehue glacier had retreated beyond these deposits and that again Rupanco meltwater was responsible for sediment deposition in the western sub‐basin of Lago Puyehue. The position of the depocentres at that time is best correlated with a possible advance of a Rupanco ice lobe south of Bahía Futacullín, as also proposed by Bentley (1997) based on onshore morphological and sedimentological observations.…”

A composite 10Be, IR-50 and 14C chronology of the pre-Last Glacial Maximum (LGM) full ice extent of the western Patagonian Ice Sheet on the Isla de Chiloé, south Chile (42° S)

“…These outwash terraces can be traced to ice-contact slopes on the east side of the Cordillera de la Costa as they have been previously mapped (García, 2012). Thus, the dating of the Cucao_T1 and Cucao_T2 terraces can help reconstruct the lLGM of the PIS and the overall glacier and climate history that preceded the wellknown LGM (MIS 2) in the region (Mercer, 1976;Laugénie, 1982;Porter, 1981;Bentley, 1997;Denton et al, 1999b). Our record builds on previous work in the Chilean Lake District (CLD) by dating glacially derived sediments that can be directly related to a landform, thereby determining the extent of glacier advances during the last glacial period.…”

Modeling the timing of Patagonian Ice Sheet retreat in the Chilean Lake District from 22–10 ka

“…Across most of our domain, moraines formed from glaciotectonized outwash (Bentley, 1996) provide evidence for an advance of piedmont glaciers across glacial outwash during the LGM, which formed the physical boundary for some of the existing terminal moraines around the lakes within the CLD (Bentley, 1996(Bentley, , 1997. The formation of ice-contact proglacial lakes likely occurred as a function of deglacial warming as ice retreated into overdeepenings in the bedrock topography and filled with meltwater (Bentley, 1996).…”