THE MODERN MORPHODYNAMICS IN THE QUARRIES OF LVIV AND ITS SUBURBS

Abstract

The seven big quarries have been explored in and around Lviv. All quarries are sandy and most of them are inactive now. There are 3 quarries located directly in the city: two – within the Znesinnia Regional Landscape Park (western and eastern) and Kryvchytskyi. The four quarries are located in the southeastern outskirt of Lviv within the Davydivskyi Chain near the villages of Davydiv (3 quarries) and Vynnychky. The processes of water erosion (sheet, rill and gully erosion), suffosion, falls, scree formation processes, slides, physical and chemical weathering are widespread in the explored quarries. The specific azonal processes such as aeolian processes (deflation and accumulation of sandy material) and formation of takyrs are also common. The most common are water erosion processes (sheet, rill and gully erosion). They are present in almost all quarries (except of Western Znesinskyi and Kryvchytskyi Quarries). These processes occur in the lower parts of quarry benches and on the slopes of dumps. They are represented by small and medium-sized erosive pre-rills and rills (width 5–30 cm, depth up to 45 cm), small gullies (depth up to 2.2 m), debris cones, deluvial cones. The sheet, rill and gully erosions mainly occur together. The suffosion processes develop in the sandy-loam deposits with low density (the Davydivskyi Quarry № 2, the Vynnychkivskyi Quarry). The result of these processes is the formation of suffosion sinkholes (35–60 cm in diameter) and suffosion “wells”. The processes of rockfalls are locally widespread on steep denudation benches of quarries, where beds of limestone or sandstone are cropped out (the Davydivskyi Quarry № 1, № 3). The scree formation processes are also common in gravitational processes and mainly occur in sandy deposits and are represented by scree cones. Slides occur rarely having small main bodies and are located on the quarry walls and dump slopes. A special type of processes in the studied quarries is the formation of takyrs, which occurs in closed watered areas of the pit floors. After the takyrs dry up, the so-called "desert papyrus" is created. Key words: modern morphodynamics, quarry, water erosion processes, falls, scree formation processes, Lviv.