Charakter dróg krążenia wód podziemnych w utworach szczelinowych górnej kredy na Wyżynie Lubelskiej
Abstract
CHARACTER OF GROUND WATER PATHS IN FISSURE FORMATIONS OF THE UPPER CRETACEOUS LUBLIN UPLAND
Summary
On the basis of a long-lasting hydrogeological research of the Upper Cretaceous formations in the Lublin Upland area, the role of fissures, which are circulation paths for ground .water, has been determined. Fissures of various type and genesis make here a net of connected channels. The most important are here large, far-reaching fissures of tectonic origin, which drain the Cretaceous massif, transecting also some surface watersheds of lower order. These fissures carry considerable amounts of water. Apart from the fissure-like character of ground water, no turbulent water movement has been ascertained even in the case of an inflow into pumped wells. On account of the existing relation between the depressed zones and dislocation fissures, a possibility has been discussed of applying hydrogeological methods for studying tectonics of the area considered. The examinations have demonstrated that a close relation exists between the surface water and ground water. The most widespread is here the drainage character of rivers that in some areas supply also ground water. In the Upper Cretaceous formations, hydraulic conditions of ground water flow are highly differentiated. This is a result of a different tectonic development of the individual portions of the area, and depends on the lithofacial changes, and on the degree of infilling of the fissures with weathered material. In several regions of the Lublin Upland there occur at places fissure systems that do not disclose any hydraulic relations to each other. At places are found also series of feebly permeable formations that are responsible for the presence of perched water tables, or for the occurrence of perched waters. In addition to the horizontal arrangement of water-bearing Cretaceous formations, also a vertical arrangement exists, frequently observed during the construction of ground water intakes.
Summary
On the basis of a long-lasting hydrogeological research of the Upper Cretaceous formations in the Lublin Upland area, the role of fissures, which are circulation paths for ground .water, has been determined. Fissures of various type and genesis make here a net of connected channels. The most important are here large, far-reaching fissures of tectonic origin, which drain the Cretaceous massif, transecting also some surface watersheds of lower order. These fissures carry considerable amounts of water. Apart from the fissure-like character of ground water, no turbulent water movement has been ascertained even in the case of an inflow into pumped wells. On account of the existing relation between the depressed zones and dislocation fissures, a possibility has been discussed of applying hydrogeological methods for studying tectonics of the area considered. The examinations have demonstrated that a close relation exists between the surface water and ground water. The most widespread is here the drainage character of rivers that in some areas supply also ground water. In the Upper Cretaceous formations, hydraulic conditions of ground water flow are highly differentiated. This is a result of a different tectonic development of the individual portions of the area, and depends on the lithofacial changes, and on the degree of infilling of the fissures with weathered material. In several regions of the Lublin Upland there occur at places fissure systems that do not disclose any hydraulic relations to each other. At places are found also series of feebly permeable formations that are responsible for the presence of perched water tables, or for the occurrence of perched waters. In addition to the horizontal arrangement of water-bearing Cretaceous formations, also a vertical arrangement exists, frequently observed during the construction of ground water intakes.