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Flujo dependiente de la densidad, transporte de solutos y mezcla en el acuífero del delta del río Fraser
Yaguang Zhu1, Kun Jia2, Roger D Beckie1
1Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, BC, Canada.
Journal of contaminant hydrology
|December 20, 2025
Resumen
El flujo de aguas subterráneas en acuíferos costeros es complejo debido a la mezcla de agua dulce y salina. La estimación precisa de la dispersividad es clave para comprender las reacciones geoquímicas durante la intrusión salina.
Área de la Ciencia:
- Hidrogeología; Geoquímica; Procesos Costeros
Sus antecedentes:
- El flujo de aguas subterráneas en acuíferos costeros depende de la densidad, lo que crea zonas de mezcla con fuertes gradientes geoquímicos.; La comprensión de la dinámica de estas zonas de mezcla es fundamental para el estudio de las reacciones biogeoquímicas durante la intrusión salina.
Objetivo del estudio:
- Caracterizar el flujo y la mezcla dispersiva en un acuífero confinado de arena que experimenta intrusión salina.; Utilizar observaciones de campo y modelado numérico para estimar los coeficientes de dispersividad y difusión.
Principales métodos:
- Se utilizó una extensa red de monitoreo para observar una cuña salina que se extiende tierra adentro.; Se empleó MIN3P para simular el flujo dependiente de la densidad y PEST++ para el modelado inverso de la dispersividad y la difusión utilizando datos de salinidad.
Principales resultados:
- Dispersividad longitudinal calibrada en 0,1 m y dispersividad transversal en 0,001 m.; Se determinó que el coeficiente de difusión molecular es de 1,2 × 10-9 m2/s.; Los análisis de sensibilidad indicaron que la dispersividad transversal impacta significativamente las características de la zona de mezcla.
Conclusiones:
- La estimación precisa de la dispersividad es crucial para modelar el ancho de la zona de mezcla y las reacciones geoquímicas asociadas.; Los hallazgos ofrecen información sobre los procesos de mezcla de agua dulce y salina en acuíferos costeros.; Proporciona orientación para la modelización futura de la dinámica geoquímica durante la intrusión salina.
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