lagerflöden

Lagerflöden, literally “layer flows,” is a term used in Swedish hydrology and geology to describe the movement of liquids through layered or stratified media, such as sedimentary rocks, soils, or aquifers. The concept emphasizes that flow properties vary between layers, leading to transport that is influenced by both in-layer flow and vertical exchange across interfaces. In a typical layered groundwater system, layers with high hydraulic conductivity conduct most of the horizontal flow, while low-permeability layers impede vertical movement; the result is often anisotropic and directionally dependent flow patterns. The arrangement and properties of the layers—thickness, conductivity contrast, and the presence of barriers or preferential paths—control the overall hydraulic response to pumping, recharge, or contaminant sources.

Modeling lagerflöden uses multi-layer representations where hydraulic conductivity is treated as piecewise constant or smoothly varying across layers. Vertical exchange terms or matrix-diffusion effects may be included in dual-porosity or dual-permeability formulations. Solutions can be analytical for simple configurations or numerical in finite-difference or finite-element schemes. Field investigations combine pumping tests, slug tests, tracer experiments, and borehole logging to estimate layer properties and validate models.

Applications of the concept include groundwater resource assessment, contaminant transport and remediation design, aquifer storage and recovery, and the planning of geothermal reservoirs. Challenges involve scaling from cores to aquifers, heterogeneity within layers, uncertainty in layer boundaries, and non-Darcian effects at high velocities or in coarse-grained settings. In Swedish literature, lagerflöden describes the layered flow phenomenon; in international terms, related concepts include stratified flow and anisotropic, layered aquifer models.