Relation Between Topography and Well Yield in Boreholes in Crystalline Rocks, Sogn og Fjordane, Norway

Abstract

Abstract Well data from about 760 wells drilled in lower Paleozoic and Precambrian hard rocks have been integrated in a database with topographic and lithologic data thought to be of importance for well yield. The database is mainly based on already existing well records supplemented by desk studies of maps. The wells were initially assigned to nine hydrogeological settings determined by rock type, and into five hydrogeological settings according to their topographic position. Statistical tests were performed to determine whether the median well yields of these groups were significantly different. Boreholes in valley bottoms and flatlands had higher well yields. The data analysis suggests that the lithologic effect on well yield may be of less importance than topography.