Revisiting Cent-Fonts Fluviokarst Hydrological Properties with Conservative Temperature Approximation

Bibliographic Details
Title: Revisiting Cent-Fonts Fluviokarst Hydrological Properties with Conservative Temperature Approximation
Authors: Philippe Machetel, David A. Yuen
Source: Hydrology, Vol 4, Iss 1, p 6 (2017)
Publisher Information: MDPI AG, 2017.
Publication Year: 2017
Collection: LCC:Science
Subject Terms: groundwater hydrology, karstic hydrology, energy budget, water energy interactions, water resource, modeling, conservative tracer, temperature, mixing, Science
More Details: We assess the errors produced by considering temperature as a conservative tracer in fluviokarst studies. Heat transfer that occurs between karstic Conduit System (CS) and Porous Fractured Matrix (PFM) is the reason why one should be careful in making this assumption without caution. We consider the karstic aquifer as an Open Thermodynamic System (OTS), which boundaries are permeable to thermal energy and water. The first principle of thermodynamics allows considering the enthalpy balance between the input and output flows. Combined with a continuity equation this leads to a two-equation system involving flows and temperatures. Steady conditions are approached during the recession period or during particular phases of pumping test experiments. After a theoretical study of the error induced by the conservative assumption in karst, we have applied the method to revisit the data collected during a complete campaign of pumping test. The method, restricted to selected data allowed retrieving values of base flow, mixing of flow, intrusions of streams, and aquifer answer to drawdown. The applicability of the method has been assessed in terms of propagation of the temporal fluctuations trough the solving but also in terms of conservative assumption itself. Our results allow retrieving the main hydrological properties of the karst as observed on field (timed volumetric samplings, geochemical analyses, step pumping test and allogenic intrusion of streams). This consistency argues in favor of the applicability of the conservative temperature method to investigating fluviokarst systems under controlled conditions.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2306-5338
Relation: http://www.mdpi.com/2306-5338/4/1/6; https://doaj.org/toc/2306-5338
DOI: 10.3390/hydrology4010006
Access URL: https://doaj.org/article/ab26b2ec8347413b9f1044159270f68c
Accession Number: edsdoj.b26b2ec8347413b9f1044159270f68c
Database: Directory of Open Access Journals