Studies focused on the Holocene series of deposits that fill dry valleys, especially common in the Łódz Plateau. The series are underlain by Vistulian complex filling dry valleys (Klatkowa 1965, 1989 a, b, 1990), Wartian fluvioglacial sands and sporadically Holocene sandy or mudy alluvia. As a rule, the Holocene sediments were directly laid down on Neoholocene fossil soils which contain charcoal in land occupation hohizons. Thickness of the studied series, approximately 1.5 m, in suitable conditions might have reached 2.8 m. Within the series, it is possible to distinguish three sedimentary members: 1. anthropogenic soil deluvia, which from the bottom, 2. deposits of gully erosion (proluvia), which cut or cover deluvia, 3. agricultural diamictons due to long-lasting ploughing, which create the top. Anthropogenic deluvia consist of two lithofacies: deluvial sands and deluvial sandy silts (Fig. 1, Fot. 1, 2). Deluvial sands (Mz = 1-3 φ, Sk₁ = 0.2-0.5, σ₁ = 0.5-2) lack of an organic admixture and from subhorizontal layers, up to a few cm thick. Organic deluvial sandy silts (Mz = 3-5 φ, Sk₁ to+ 0.6, σ₁ = 1.75-2.75) create layers of a similar thickness and reveal subtle internal lamination. Deluvial sands and sandy silts alternate, which gives a character of rhythmicallity. The rhythmicallity is additionally underlined by the variation of colours of the lithofacies, which occurs by the different content of an organic admixture. Rhythmical lamination is a general feature of deluvial sediments (Stochlak 1976, 1978, 1996, Teisseyre 1994) and is explained by variable activity of wash process in time and its modes (sheetwash, rillwash) . Deposits of gullying occasionally interlayer the deluvial member (Photo 1, 2). They are coarse-grained (Mz = - 6 to 1 φ), very poorly sorted ( σ₁ to 5.5) and contain an admixture of coarser (Sk₁ = -0.3 to -0.5) gravel and boulder particles. This sediment type must have been deposited under turbulent flow condition of episodic waters. The development of gullies took place after deluvial deposition between V/VI and XVI century AD (Twardy 1995), and often provided conditions for partial destruction of the older deluvial member. Development of agricultural diamictons (Niewiarowski et al. 1992, Sinkiewicz 1994, 1995) followed the introduction of a plough, and afterwards inccreased in XIX and XX century with the use of agricultural machinery. Vari-grained, structurless, compact and organic deposits originated, whose structure is due to soil mixing during ploughing (Photo 1, 2). In the Łódź region, the start of the deluvial deposition occurred at the turn of the Bronze and Iron Age and coincided with the settlement of farming tribes.
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