Extended Data Fig. 4: Comparison of glacier fluctuations in Fiordland and western Patagonia.
From: Synchronous bipolar retreat of mid-latitude ice masses during Heinrich Stadials
a, Mass accumulation rates (MAR) of n-alkane (continuous line) and dry bulk density (DBD; dashed line) at site MR16-09 PC03 (Fig. 1), southeast Pacific (46°S), as marker for fluctuations of the southern Patagonian ice field (SPI)50. Based on these data and the original interpretation in ref. 50, we propose below a summary view of ice fluctuations (that is mass balance changes) in this region (ice growth for MAR n-alkanes > 3000 mg/ka.cm2 and DBD > 0.65 g/cm3). b, Glacier chronologies for eastern SPI (51-53°S) from 10Be moraine dating (probability plots with their age uncertainties generated with Chronomodel 2.0 Bayesian software113,114,115; y-axis on arbitrary scales)124,125,126. The Local LGM (LLGM) at these latitudes occurred ca. 47 ka (green triangle in a)37. The high preservation of moraines from ca. 30-25 ka onwards (n = 12) highlights the first-order net decrease in glacier extent in Patagonia37. All published 10Be exposure ages were homogenised using the CREp online calculator120 and the SH calibration sites121,122. c, Mean εNd values of the clay-silt fractions of the detrital sediment at TAN1106-28 (blue; ±2σ, blue shading), and the Fiordland GI (grey). A summary view of ice fluctuations in the Fiordland region from TAN1106-28 is shown ( = first-order changes in εNd values; see Fig. 2c). The timing of the Fiordland Otiran (FO) glacier maxima (including the Fiordland LLGM at ca. 45 ka, FO6) are also shown. Marine Isotope Stages (MIS) are numbered.
