Procesy rzeźbotwórcze w okolicy Kazimierzy Wielkiej

Obszar Kazimierzy Wielkiej zbudowany jest z ilow krakowieckich, na ktorych lezą rezydua morenowe i lessy plejstocenskie. Dzialalnośc procesow rzeźbotworczych i ich wyniki ujeto w piec cyklow. Pierwszy cykl doprowadza do powstania dolnopliocenskiej powierzchni zrownania, w drugim procesy endogeniczne, silniej dzialające w polnocno-zachodniej niz w poludniowo-wschodniej cześci, i zwilgotnienie klimatu ozywiają erozje i doprowadzają do powstania gornopliocenskiej powierzchni tektoniczno-erozyjnej, w trzecim wymieniona powierzchnia zostaje przykryta osadami glacjalnymi i tworzy sie plejstocenska powierzchnia denudacyjna. W czwartym cyklu procesy eoliczne, w tym lessotworcze, powodują powstanie pol deflacyjnych z wielograncami i akumulacyjnej, plejstocenskiej powierzchni lessowej. W piątym cyklu erozja, denudacja i akumulacja, zywe i trwające nadal, tworzą holocenską powierzchnie erozyjno-denudacyjno-akumulacyjną.· RELIEF-FORMING PROCESSES IN THE KAZIMIERZA WIELKA REGION The paper presents reconstruction of five cycles in development of relief-forming processes in the Kazimierza Wielka region (Fig. 1) and their effects. First of these cycles began with uplifting movements responsible for regression of the Early Sarmatian sea and resulting erosion. This cycle was continuing till the Early Pliocene, being responsible for origin of Early Pliocene peneplain (Fig. 2a). The second cycle began with tectonic disturbances connected with Late Pliocene orogenic movements (Figs. 3, 12, 13). The disturbances and accompanying increase in humidity of climate resulted in advancement of erosion and origin of Late Pliocene erosional surface (Fig. 2b). The third cycle began with cooling of the climate and advance of icesheet, leading to glacial accumulation and interglacial erosion and, therefore, to origin of Pleistoeene denudational gravel surface (and, locally, some remains of morains). The fourth cycle began with an onset of eolian processes, related to periglacial climate from lime of the North·Polish Glaciation. It resulted in reshaping of erratic boulders present on erosional terraces in valleys into ventifacts (Table I, Figs. 1 -5) and covering of plateau with loesses. The final result of it is the formation of Pleistocene loess accumulational surface. The fifth cycle began in the Early Holocene with downward and lateral erosion, initiating formation of floodplains exposing Late Pleistocene erosional terraces (Figs. 4, 5, 6). The phenomena of exposition of the erosional terraces were mainly due to suffosion (Figs. 9, 14). Exposition of clay surface above the terraces was connected with origin of loess escarpments as well as marshy grounds and ponds at their foot (Figs. 7, 8). In comparison with south-eastern part of the studied area, north-western part was not characterized by development of erosional terraces at valley slopes but erosional-karst ridges. In some places, for example at Wrocimowice, suffosion processes acting at valley slopes resulted in subsidence of terrain surface (Fig. 9), reflected by fracturing of walls in some buildings (Figs. 10, 11). It may be concluded that the relief-forming processes active in the Holocene resulted in origin of erosional-accumulational peneplain here (Fig. 2c).