Periglacial morphogenesis in the Paris basin: insight from geophysical survey and consequences for the fate of soil pollution

The evolution of periglacial patterned ground in East Anglia, UK

“…The lack of older wedges Buylaert attributed to sampling bias and/or erosion and/or less favourable conditions. North‐west of Paris, France, sand‐filled polygonal patterns about 20–30 m in diameter (twice that of the features described in the present study and apparently lacking stripes) are thought to have initiated by thermal contraction cracking during the Saalian glaciation (∼160 ka), with repeated episodes of periglacial activity and aeolian deposition during the Saalian and Weichselian, although these features have not been dated (Thiry et al ., ). We know of no relict patterned ground features directly comparable in size and morphology in northern and central Europe to those in East Anglia.…”

“…The utility of relict periglacial landforms in understanding palaeoenvironments has often been hampered by age uncertainties and the potential for near-surface features to be a palimpsest formed by multiple phases of activity (e.g. Paris basin, Thiry et al, 2013). Despite its complex glaciological history, the East Anglia region of the UK (Fig.…”

Soil Processes, Pedofeatures and Microscale Metal Distributions: Relevant Study of Contaminant-Dynamics Calls for Pedology-Based Soil-Depth Sampling Strategies

“…Metal-concentration profiles point to the migration of Zn, Cd and Cu towards depth, and Zn-interception in the Bt horizon. The geological substratum and the soil cover underwent strong cryoturbation during the late Pleistocene [32]. In such polygonal soils, additional soil survey was performed in deep trenches giving access to the morphology and thickness of soil horizons [32], and revealed deep bending of the clay-rich Bt horizon into the carbonated substrate, until 1.5-2-m depth.…”

“…The geological substratum and the soil cover underwent strong cryoturbation during the late Pleistocene [32]. In such polygonal soils, additional soil survey was performed in deep trenches giving access to the morphology and thickness of soil horizons [32], and revealed deep bending of the clay-rich Bt horizon into the carbonated substrate, until 1.5-2-m depth. In these soil trenches additional bulk sampling and collecting of about 50 undisturbed samples guaranteed the representativeness of samples.…”

“…Many allochthonous particles, such as charcoal, plastic fragments, and occasionally industrial slag (Figure 4a, 2-4) were observed, as well as phosphates and fishbone fragments. The upper part of the E horizon displayed very little fine plasma between the sand grains (Figure 4c), but locally, fine dark-brown fibers were observed ( Figure 4d) and ascribed to capillary rising of suspended fine soil particles from the clay-rich Bt horizons, issued by strong drying of the sandy surface after repetitive irrigation events [18,32]. In addition, silty-clay textured, non-translucent dusty coatings were frequently observed (Figure 4e), illustrating the downward moving of fine material out of the Ap horizon during fast rewetting after wastewater flooding.…”