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El desgaste de guijarros no sólidos en las cabeceras de los ríos
Science (New York, N.Y.)
|January 12, 1979
Resumen
La ley de Sternberg predice con precisión el desgaste de las piedras sólidas, pero falla para las no sólidas. Se propone un nuevo modelo donde el coeficiente de desgaste cambia con la distancia, mejorando las predicciones para el transporte de guijarros no sólidos.
Área de la Ciencia:
- Geomorfología Geomorfología.
- La sedimentología sedimentológica.
- Ciencias del medio ambiente Ciencias del medio ambiente.
Sus antecedentes:
- El transporte de guijarros y la intemperie son procesos geomórficos cruciales.
- La ley de Sternberg es un modelo ampliamente utilizado para el desgaste de guijarros.
- Las características iniciales del guijarro (por ejemplo, falta de solidez) pueden afectar la dinámica de desgaste.
Objetivo del estudio:
- Evaluar la aplicabilidad de la ley de Sternberg a los guijarros no sólidos.
- Desarrollar un modelo alternativo para el desgaste de guijarros no sólidos.
- Para comparar el poder predictivo de la ley de Sternberg y el nuevo modelo.
Principales métodos:
- Análisis de los datos de desgaste de guijarros de los sistemas fluviales, específicamente la cuenca de Clutha.
- Comparación del desgaste de guijarros observado con las predicciones de la ley de Sternberg.
- Derivación y aplicación de una ley de desgaste modificada donde el coeficiente varía con la distancia.
Principales resultados:
- La ley de Sternberg describe mal el desgaste de guijarros no sólidos en las cabeceras de los ríos.
- El coeficiente de Sternberg para guijarros no sólidos disminuye aguas abajo, violando el supuesto de constancia de la ley.
- Un nuevo modelo, donde el coeficiente de desgaste es inversamente proporcional a la distancia recorrida, muestra una mejor adaptación para guijarros no sólidos.
Conclusiones:
- La suposición de la ley de Sternberg de un coeficiente de desgaste constante es inválida para guijarros no sólidos.
- El modelo alternativo propuesto ofrece una mejor descripción de la dinámica de transporte de guijarros.
- La comprensión de los coeficientes de desgaste variables es esencial para el modelado geomórfico preciso.
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