C - Lublin

Fig.1. Micromorphology of quartz grains from the Pleistocene sediments in the Upper
Oka River Basin: А – grains formed as a result of glacial transport; B – grains with the
traces of water reworking; C – grains with the traces of wind reworking; D – adhering
clays particles as a result of diagenesis; E – traces of cryogenetic weathering.
D
Commonly present on the majority of studied grains, are adhering clays
particles forming accumulations of different thickness both on the exposed grain
surfaces and within the fracture planes and depressions (Fig. 1-D). They are
perhaps the result of diagenesis (Krinsley, Doornkamp, 1973). Solution pits and
crevasses are probably the result of in situ chemical weathering. The content of
grains with such surface features increases in cover loams deposits and can be
explained by the activity of soil processes. Many grains carry the traces of
cryogenic weathering, which is reflected in the presence of fresh conchoidal
fractures on the grains surface (Rogov, 2000; Fig. 1-E).
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