Plejstocen doliny Panwi w rejonie Lublińca

Abstract

THE PLEISTOCENE OF THEMALAPANEWRIVERVALLEYOF THE LUBLINIEC AREASummaryThe depression of the Mala Panew river is surrounded on the south and north by tresholds represented by hills built of Middle and Upper Triassic limestones (Fig. 1). Less resistant substratum between these tresholds, built of Keuper and Rhaetian clays, predisposed formation of a depression in which river valleys were cut in the early Eopleistocene, and the Cromerian, Masovian and Eemian interglacials.During the Eopleistocene, sands and gravels were deposited in the ancient valley funning NE of Wielowieś (Fig. 2), In the Cromerian Interglacial, sands were deposited in a valley running beneath the recent river. The sands were covered by stagnant-lake deposits before the Cracow Glaciation. Deposits of that glaciations are represented here by a continuous till layer in SE part and by erosional patches of tills and residuum of glacial deposits in the remaining parts of the area studied.Solifluction deposits (Figs. 3, 6) originated under periglacial conditions prevailing at the end of the Cracow Glaciation and the beginning of the Masovian Interglacial.During the Masovian Interglacial a deep valley was eroded north of the recent river and subsequently buried. The highland area was subjected to an intense denudation, in places exposing Triassic substratum (Fig. 3). The icesheet of the maximum stage of the Mid-Polish Glaciation covered the entire Mala Panew river depression, whilst subsequent icesheets did not reach that area. Glacial relief was later obliterated except for kame hill in the vicinity of Wielowieś (Fig. 5). The highland was denuded and deep river valleys subparallel to the recent valley were formed during the Eemian Interglacial (Fig. 4). The ancient valleys were buried during accumulation cycle continuing till the maximum stage of the Baltic Glaciation. Fluvial deposits also buried the depressed part of the highland, forming the Baltic river terrace (Figs. 5, 6). Denudation of the highland proceeding under periglacial conditions exposed the bedrock in some places and it resulted in origin of solifluction covers. Solifluction flows sometimes interfinge with valley deposits.Peats dated at the end of the Eemian or the beginning of the Baltic Glaciation (T. Kuszel, M. Włodek, 1974), covered by deposits of such flow, are known from Potępa village. Peats and solifluction flows make possible rough delineation of the Eemian/Baltic Glaciation boundary in fluvial deposits.Two lower terraces of the Mała Panew valley originated in the Holocene.