Natural aquifers may contain multi-scale media heterogeneity, but their combined impact on solute transport is still unclear. To fill this knowledge gap, this dataset selected an alluvial aquifer as a representative medium, where the spatial distribution of multiple water phases (typical non-uniform hydraulic conductivity (K) within each phase) can represent heterogeneity at the regional scale (large-scale) and sub water phase scale (local scale). In order to obtain first-hand information, field tracing experiments were conducted in the alluvial aquifer of Tongzhou area, Beijing, China. Breakthrough curves (BTC) obtained at different depths of the aquifer showed that regional and sub water phase scale heterogeneity had a significant impact on solute transport. Further numerical analysis shows that the influence of regional heterogeneity on solute transport increases with the increase of the difference in K values between adjacent water phases. In contrast, when the average Ks values of adjacent water phases are closer, the heterogeneity of the sub water phase scale embedded in each water phase plays an important controlling role in solute transport. Early bimodal transport was mainly influenced by multi-scale preferential flow paths, while later solute retention was mainly affected by the stationary zone of later transport. Anomalous transport caused by multiscale heterogeneity can be captured by the Dual Heterogeneous Domain Model (DHDM), while the Dual Advection Dispersion Equation (DADE) and Fractal Movement Non Movement (fMIM) models can only provide reasonable predictions in the early and late stages, respectively. This study reveals the control mechanism of multiscale heterogeneity on solute transport.
The data was measured by on-site experimental instruments.
On site tracing experiments combined with numerical analysis.
The data quality is good.
This work is licensed under a
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CSTR:11738.11.NCDC.ZENODO.DB4019.2023
10.5281/zenodo.7188052