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Figure 9. Results of extended analyses of the Paraiso section. Stratigraphic sketch includes general sampling points (yellow circles), positions 
of luminescence (red boxes) and heavy mineral samples (blue circles labeled SM), stratigraphic units (SU), and glacial and GS events. (A) 
Particle-size index (PSI; (fine sand + coarse silt)/(medium silt + fine silt + clay)), reflecting wind strength. Grey arrows indicate increasing/ 
decreasing wind strength. (B) Clay content (upper scale) with (red line) and without (blue line) prior decalcification. (C) Odd-over-even pre- 
dominance (OEP) of n-alkanes (light purple line and upper scale) as an indication of preservation (higher values imply better preservation). (D) 
Average chain length (ACL) of n-alkane homologues (black line and lower scale) (Schäfer et al., 2016a), with values > 30 indicating grass 
vegetation and < 30 pointing to tree and shrub vegetation, based on comparative studies on mid-European n-alkane patterns (e.g., Schäfer 
et al., 2016b). (E) 8'°C values of the most abundant n-alkane compounds n-C,9 (red) and n-C3, (blue) as indicator for environmental moisture 
availability. Solid red arrows indicate increase, dashed red arrow indicates decrease. (F-H) Results of heavy mineral analyses with relative 
proportions of apatite (F; in red, lower scale) indicating slope supply, relative proportions of garnet (G; in green, upper scale), and relative 
proportions of tourmaline and dolomite (H; in blue, lower scale), indicating contributions of deflated Tagus River sediments and thus, 
nigh weathering dynamics in the framing mountain ranges due to presumably cold temperatures (Wolf et al., 2019). (I-L) Results of rock 
nagnetic measurements with: mass-specific magnetic susceptibility (x300 Hz in 107% m’kg”') (D; absolute frequency dependence of 
mass-specific magnetic susceptibility (Xsa in 107% m’kg”') indicating presumably pedogenic enrichment of superparamagnetic particles 
SP) (J); the s-ratio [(IRM;9o/IRMo00o + 1)/2] (K); and IRM,000/x300 Hz in 103Am”' (L) as an indicator of relative hematite content. (For 
interpretation of references to color in this figure caption, the reader is referred to the web version of this article.) 
soil-forming processes. Therefore, micromorphological fea- 
ures of the main palaeo surfaces (PS) were analyzed. 
Micromorphological analyses of the loess sections in the 
Parafso and Fuentiduena sections show a general uniformity 
in the groundmass of the material, which consists of well- 
sorted silt with minor amounts of sand grains. The apedal 
material is characterized by a channel microstructure and a 
caleitic erystallitic b-fabric (Fig. 11), due to micrite produced 
as a product of weathering of sediment rich in calcite 
‚Boixadera et al., 2015). The soil formation processes related 
to the palaeo surfaces are minimal, mainly consisting of 
bioturbation and different degrees of carbonate/gypsum 
redistribution. 
Table 1 presents an overview of different types of calcite 
enrichment or depletion pedofeatures as well as gypsum 
pedofeatures that were detected in the thin sections. Gener- 
ally, the sequences can be divided into three parts. 
First, in the lowest part comprising units SU-4 to SU-6 
{PS-1 to PS-3), the occurrence and distribution of carbonate 
dissolution and accumulation features indicate the strongest 
phases of pedogenesis. Despite the dominance of micritic 
impregnation of the material in PS-1, a weak dissolution of 
carbonate took place, resulting in a formation of residual 
clay partly enveloping mineral grains without a complete 
decalcification of the material (MD, Table 1). This process 
did not impair the calcitic crystallitic b-fabric of the sedi- 
ment. Decalcification can be observed along some biogenic 
voids forming depletion hypocoatings (DH, Table 1) with a 
speckled b-fabric in PS-1, PS-2, and PS-3. These features are 
formed by removal of calcite in solution (Durand et al., 
2010). The decalcification tendency that can be observed 
n PS-1 indicates that some moist environmental conditions 
allowed subsequent weak carbonate dissolution following 
‚ts sedimentation. PS-2 lacks depletion pedofeatures but 
shows carbonate enrichment in the form of calcitic hypo- 
coatings (CH, Table 1) of voids and a strong micrite impreg- 
aation of the matrix. There are two main hypotheses 
concerning the formation of calcitic hypocoatings (Becze- 
Deäk et al., 1997; Barta, 2011): they form from soil solutions 
percolating along the pores and penetrating into the matrix 
‘Kemp, 1995; Durand et al., 2010); or they represent rapid 
accumulations in connection with root metabolism (water 
suction and desiccating effect, Wieder and Yaalon, 1982). 
Generally, calcitic hypocoatings are formed under arid and 
semiarid conditions (Durand et al., 2010) with a patchy veg- 
etation cover, probably during phases of loess accumulation 
(Barta, 2011). Although hypocoatings indicate dry formation 
conditions, some percolation during periodic moister 
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