Implications of the geochemistry of L1LL1 (MIS2) loess in Poland for paleoenvironment and new normalizing values for loess-focused multi-elemental analyses

Abstract

Loess paleoenvironmental reconstructions on regional to supra-regional scales have recently gained much attention. Geochemistry comparisons in relation to reference datasets, such as the Upper Continental Crust (UCC) data, have furthered our understanding of the climatic and geomorphological conditions under which terrestrial sites have developed. However, UCC data differs from loess, thereby obscuring important features, and the existing “average loess” datasets also are not sufficient for modern investigations. In this study, we examine the youngest Polish loess (L1LL1 = MIS 2, ca. 26–15 ka) for its suitability as a new, loess-focused reference dataset. Eighty-nine samples from seven sites were analyzed, using inductively coupled plasma spectrometry. The loess had assumedly been homogenized during transportation and/or sedimentary recycling (LaN/SmN = 3.34–4.06, median 3.78; Eu/Eu* = 0.46–0.66, median 0.55; GdN/YbN = 1.08–1.49, median 1.26), and weakly affected by pre- or post-depositional weathering (CIA = 53.64–69.12, median 57.69). The statistically significant differences between sites in elemental medians were mostly conditioned by variations in grain size and in the “fresh” to “re-deposited” sediment ratio. Nonetheless, the overall geochemical composition homogeneity provided a basis for the estimation of Polish Median Loess (PML) data, as determined for 41 chemical elements. When used, PML data highlight differences between loess regions in Europe, thereby providing a tool for cross-continental comparisons.

Electrical resistivity tomography as a modern tool for identifying loess covers – case study the Magdalenian site Wilczyce 10 (Sandomierz Upland, Poland)

“…These thick nesses are also typ ical for periglacial loess of the Weichselian age in Eu rope and fall within the av er age val ues be tween the "oce anic" thin loesses of the west ern part of the con ti nent and the several-metre or over 20 m thick ness doc u mented in the con ti nental east (e.g., £anczont et al, 2022). The thick ness of the L1 loess here is sim i lar to that of loesses of this age de scribed in the nearby, key-site of Z³ota (also known as Polanów Samborzecki; e.g., Dolecki and £anczont, 1998;Jary, 2007;Mroczek, 2013;Moska et al, 2015;Skurzyñski et al, 2024). These sites dif fer geomorphologically: Wilczyce is sit u ated on a loess pla teau, whereas Z³ota lies at the edge of a loess patch, ad ja cent to the Vistula River Val ley.…”

“…Pol ish periglacial loess typ i cally com prises quartz (60-80%), aluminosilicates (10-20%), iron ox ides (sev eral percent), and cal cium car bon ate (up to 15%; Skurzyñski et al, 2019Skurzyñski et al, , 2024Skurzyñski, 2020). Mi nor quan ti ties of micas, glauconite, phos phate rock, and heavy min er als are also present (Malinowski, 1971;Racinowski, 1976;Chlebowski and Lindner, 1991;£anczont and Wilgat, 1994;Maruszczak and Wilgat, 1995).…”