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£- Niodzmtumska

The top senes ts finer, and it incłudes predominantly sandy dusi and dum sands. A fiat paralleł lamination dominates ihere. However, a great number of strata, but espedally the topmost ones do not show scdimentary structures ai all- In some cases this may be due to pedogenic processes. M: of the fine saod and dusi (up to 40%) is 3-3—4.0 0. This deposit is pooriy and very poorly sorted (er, = 1.5 — 2.9). Mz of the sandy dusts varies from 4.2 to 6.0 0. Tfaey aie poorly and very pooriy sorted (o, = 1.2—3.3). The Wo values (790—1020) of the coarse-grained strata point to a better abrasion than that of the fme-grained stratified strata (Wo = 830 — 990).

In the long profile the sequence of sediments is similar to that in the verticaJ profile, only strata decrease in thickness downstream (Fig. 9). In eadi of the profiies analysed, the diversity of extreme values of the grain size indkes ii greater than that in the long profile (Tab. 4). It appears that both grain size and sorting do not essentially change downstream. This is a typical feature of smali alluvial fans.

TabJe 4. Minimum and muimum valucs of both grain size indices and abrasion indkes of u Atlantic aDuvial fan at Podgrodzie site

Profiies	Mz [0]		Sfc,	Kg	Wo	*•
A	1.7—6.0	08-33	-03-06	03-24	790-1020	26-43
Al	1.2—5.7	06-24	-04-04	1.0-32	910-1050	29-43
AIV	2.2-6J	07-29	01-0.6	07-1.8	770-1030	28-42
AV	1.6—5.4	07-28	-04-0.6	07-21	850-1080	25—4.7
AVI	2.6—63	09-28	*>-02-05	08-1.7	830-1020	3 rn 1 iń ri

CLS.I.

Fig 11. Drogomyśl site — schematic geological scction across the (loodplain. Fxplanatimis« •

Figurę 4