Comparative study of transient hydraulic tomography with varying parameterizations and zonations: Laboratory sandbox investigation

JOURNAL OF HYDROLOGY

卷:554

Article

Luo, Ning¹  Zhao, Zhanfeng^1,2  Human, Walter A.¹  Berg, Steven J.^1,3 

[1] Univ Waterloo, Dept Earth & Environm Sci, Waterloo, ON N2L 3G1, Canada

[2] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Beijing, Peoples R China

[3] Aquanty Inc, Waterloo, ON N2L 5C6, Canada

关键词: Aquifer heterogeneity;    Hydraulic tomography;    Transient analysis;    Geological information;    Inverse modeling;    Model calibration and validation;    Model comparison;   

DOI  :  10.1016/j.jhydrol.2017.09.045

来源: Elsevier

【 摘 要 】

Transient hydraulic tomography (THT) is a robust method of aquifer characterization to estimate the spatial distributions (or tomograms) of both hydraulic conductivity (K) and specific storage (S-s). However, the highly-parameterized nature of the geostatistical inversion approach renders it computationally intensive for large-scale investigations. In addition, geostatistics-based THT may produce overly smooth tomograms when head data used to constrain the inversion is limited. Therefore, alternative model conceptualizations for THT need to be examined. To investigate this, we simultaneously calibrated different groundwater models with varying parameterizations and zonations using two cases of different pumping and monitoring data densities from a laboratory sandbox. Specifically, one effective parameter model, four geology-based zonation models with varying accuracy and resolution, and five geostatistical models with different prior information are calibrated. Model performance is quantitatively assessed by examining the calibration and validation results. Our study reveals that highly parameterized geostatistical models perform the best among the models compared, while the zonation model with excellent knowledge of stratigraphy also yields comparable results. When few pumping tests with sparse monitoring intervals are available, the incorporation of accurate or simplified geological information into geostatistical models reveals more details in heterogeneity and yields more robust validation results. However, results deteriorate when inaccurate geological information are incorporated. Finally, our study reveals that transient inversions are necessary to obtain reliable K and Ss estimates for making accurate predictions of transient drawdown events. Crown Copyright (C) 2017 Published by Elsevier B.V. All rights reserved.

【 授权许可】

Free