Schematic diagram of CATHERINE. The piezometer is located in an aquifer adjacent to a river, lake or sea.
Influence of tides on the aquifer level in Martinique. Sea levels and piezometer levels observed at hourly intervals.
Application example n° 2: Influence of air temperature on temperature in a chalky soil. Variation in temperatures measured at depths of 20, 200, 400 and 650 cm, from 2006 to 2010.
CATHERINE is an acronym of "CAlcul THEorique de l’influence d’une RIvière sur des NIveaux de nappe" (Theoretical calculation of river influence on groundwater levels).
CATHERINE offers a simple means of performing the following operations:
For an aquifer with a rectilinear boundary (river, lake or sea) whose level varies over time:
- To calculate the hydraulic diffusivity of an aquifer from monitoring of simultaneous variations over time of the piezometric level at a given point in the water table and the water level in a river, lake or sea. If the storage coefficient is known, transmissivity (and permeability) can be deduced. Conversely, if the transmissivity is known, the storage coefficient can be deduced.
- To calculate variations in the piezometric level at a given point in an aquifer with known diffusivity and bounded by a river, lake or sea where the variations in height over time are known.
- To correct a piezometric level for water level variations due to tides, to the passage of a flood or to a dam release. The corrected piezometric level can then be used to interpret a pumping test or to model the relationship between rainfall and water level.
For energy transfer calculations, the following operations can be performed:
For an aquifer or soil area with a rectilinear boundary (river, lake or sea) whose temperature varies over time:
- To calculate the thermal diffusivity of an aquifer from monitoring of the simultaneous variations over time of the temperature at a given point in a heat-conducting medium (e.g. soil or immobile groundwater) and the temperature at a boundary. If the thermal conductivity is known, the calorific capacity can be deduced. Conversely, if the calorific capacity is known, the thermal conductivity can be deduced.
- To calculate temperature variations at a given point with known thermal diffusivity and where the temperature variations of the boundary are known. Thermal variations in a soil area can then be worked out from changes in the surface (or air) temperature.
- Correction of temperature variations due to temperature variations on a soil surface. The corrected temperatures can then be used to analyse the efficiency of a heat storage facility.
The analytical solution method is very easy to apply.
CATHERINE can determine the parameters to be used with the MARTHE application.
Free licensing available
CATHERINE is available for downloading for Windows 8 ou 10.