Identifying Basin-scale Heterogeneity of Soil Properties Using River Stage Tomography

Abstract:

Observations and simulation of soil heterogeneity were carried out to understand the characteristics of the soil properties in the alluvial fan of Chuoshui river, Taiwan. The fan is located at middle Taiwan with an area of 1800 km² and has at least one unconfined and three confined aquifers. All aquifers are connected to each other at apex of the fan.

The distribution of soil hydraulic conductivity was estimated by fusing naturally recurrent stimuli and groundwater head. Specifically, the covariance and correlation information provided by temporal and spatial change of groundwater head in response to river stage variations are used to estimate heterogeneity of hydraulic conductivity. The results of the estimate compared with other geo-investigate method are discussed.

Keywords: river stage tomography, hydraulic tomography, heterogeneity, hydraulic conductivity