An accumulation of glacial sediments is located near Písečná village in the depression between the Sokol Ridge
and Zlaté Hory Highlands NNE of Jeseník town (Eastern Sudetes). The accumulation lies at the lateral side
of the mountain valley of the Bělá River and fills a preglacial palaeovalley of this river. Research combining
facies analysis of outcrops, ground penetrating radar survey, interpretation drilling survey, and modelling of
the preglacial relief was undertaken at the site. According to the results obtained, the upper part of the sedimentary
accumulation represents a coarse-grained terminoglacial glaciofluvial delta of the Gilbert type. The
development of the accumulation has dominantly been driven by the preglacial morphology. Facies typical for
foresets of coarse-grained deltas represented mainly by high-density flows, cohesionless debris flows, debris
falls and less common low-density flows were found in the outcrops. The delta near Písečná prograded into
a lake dammed by the ice-sheet front in the north. The lake was bounded by the slopes of Sokol Ridge, Zlaté
Hory Highlands and Góry Parkowe on other sides. The lake level reached an altitude of up to 430 m a.s.l., as
the coarse-grained delta plain base lies at this level.