Artificial Tracer Techniques for the Determination of the Structure of Conduit Aquifers

Abstract

ABSTRACT Fluorescent dye tracer technology now permits accurate determination of tracer breakthrough curves in karst hydrology. Such data may be evaluated in terms of hydraulic processes of dispersion, divergence, convergence, dilution, and storage. The breakthrough curve reflects the character of ground‐water flow and the structure of the ground‐water conduit network, so that within constraints of regional geology, geomorphology, and hydrology, it is possible to interpret tracer breakthrough curves to produce a structural model of a karst aquifer. Such structural models provide a basis for further field investigations and rational computer modeling. An example of such an approach is taken from a series of tracer tests on the Castleguard karst aquifer, Alberta, Canada, an alpine karst with rapid conduit flow, and a strongly seasonal flow regime. A dimensionless recovery index is developed to identify the relationship between springs, and this shows that the behavior and configuration of the active aquifer vary dramatically with discharge.