Czwartorzęd dorzecza górnej Mierzawy

Abstract

Badania czwartorzędu w dorzeczu górnej Mierzawy wykazały, że bezpośrednio na osadach węglanowych kredy górnej występują resztki mułków i glin zwałowych zlodowacenia południowopolskiego. Doliny rzeczne wypełnione są mułkami i piaskami zlodowacenia środkowopolskiego. Osady kredowe i plejstoceńskie na wyniesieniach przykrywają częściowo lessy i deluwia zlodowacenia północnopolskiego, doliny zaś wypełniają piaski humusowe i torfy holoceńskie.

QUATERNARY OF UPPER MIERZAWA DRAINAGE BASIN

The studied area is situated in the Upper Mierzawa drainage basin, western part of the Jędrzejów plateau. Upper section of the Mierzawa valley was trending N-S until the South-Polish Glaciation. The flow of waters to the north was subsequently dammed by advancing icesheet and a gorge originated west of Mstyczów.

Loess silts, ice-dammed lake clays and bipartite tills originated at that time.

The Great Interglacial was characterized by erosion of glacial deposits resulting in excavation of pre-Pleistocene relief. This process still continues.

No traces of the stay of the Mid-Polish icesheet were found in the studied area. At these times originated silts and sands at present occurring in valleys and depressions situated about 270 m a.s.l. The Eemian Interglacial was characterized by the action of denudational processes on slopes and deepening of valleys. No deposits of that Interglacial were found here.

Sandy terrace 2.5 to 4 m high originated during the North-Polish Glaciation. Periglacial climate from that time was favourable for mass movements, the effects of which include solifluction flows and thick Cretaceous waste covers. The Holocene is characterized by development of denudation processes on slopes and accumulation of sands, silts and peats on valley floors.