Delineation of groundwater potential zones by means of ensemble tree supervised classification methods in the Eastern Lake Chad basin

This paper presents a machine learning method to map groundwater potential in crystalline domains. First, a spatially-distributed set of explanatory variables for groundwater occurrence is compiled into a geographic information system. Twenty machine learning classifiers are subsequently trained on...

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Detalles Bibliográficos
Autores: Gómez-Escalonilla Canales, Víctor, Vogt, Marie-Louise, Destro, Elisa, Isseini, Moussa, Origgi, Giaime, Djoret, Daira, Martínez Santos, Pedro, Holecz, Francesco
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/6765
Acceso en línea:https://hdl.handle.net/20.500.14352/6765
Access Level:acceso abierto
Palabra clave:556.3(674.3)
Remote sensing
groundwater exploration
machine learning
Lake Chad basin
Hidrología
2508 Hidrología
Descripción
Sumario:This paper presents a machine learning method to map groundwater potential in crystalline domains. First, a spatially-distributed set of explanatory variables for groundwater occurrence is compiled into a geographic information system. Twenty machine learning classifiers are subsequently trained on a sample of 488 boreholes and excavated wells for a region of eastern Chad. This process includes collinearity, cross-validation, feature elimination and parameter fitting routines. Random forest and extra trees classifiers outperformed other algorithms (test score > 0.80, balanced score > 0.80, AUC > 0.87). Fracture density, slope, SAR coherence (interferometric correlation), topographic wetness index, basement depth, distance to channels and slope aspect proved the most relevant explanatory variables. Three major conclusions stem from this work: (1) using a large number of supervised classification algorithms is advisable in groundwater potential studies; (2) the choice of performance metrics constrains the relevance of explanatory variables; and (3) seasonal variations from satellite images contribute to successful groundwater potential mapping.