Volcanic ash dating what rhymes with intimidating
The shards of AUC1 were all transparent and vesicular, with a mean size of 53 μm, median = 50 μm, maximum = 125 μm, and minimum 25 μm or less (n = 40).
There is no clear event in the core properties (moisture content, loss-on-ignition or peat humification) that corresponds with the tephra layer.
Total Alkali-Silica (TAS) and geochemical bi-plots were constructed for comparison of the published tephra geochemical data with geochemical data from the AUC1 tephra.
Figure 1 shows the location of Aucayacu peatland in Amazonia and volcanoes discussed in the text.
However, tropical peats are notoriously difficult to date due to the presence of large roots leading to deep biological alteration.
Tephra layers which transgress continental boundaries provide the opportunity for the correlation of palaeoenvironmental records over large distances.
Geochemical data is provided in supplementary table 1.
Only one of these volcanoes, Chacana (Ecuador) is described as having a rhyolitic dominant rock type.
This (layer) is merely a trace of (volcanic) material and would not have been detected through visual means or analysis of basic core properties.
Aucayacu peatland is within cryptotephra fallout range for a moderate to large eruption from volcanoes in Peru, Ecuador and Colombia.