A stepwise approximation for estimations of multilevel hydraulic tests in heterogeneous aquifers PRESENTER: YI-RU HUANG ADVISOR: CHUEN-FA NI DATE: /3/101

Outline  Objective  Methodology  Conclusions  Results & Discussion  Future work  Introduction  Motivation 2011/3/102

Introduction  Ground water investigations have relied on the determination of aquifer parameters.  Knowledge of detailed spatial distributions of hydraulic properties is important to improve our ability to predict water and solute movement in the subsurface.  Ground water investigations have relied on the determination of aquifer parameters.  Knowledge of detailed spatial distributions of hydraulic properties is important to improve our ability to predict water and solute movement in the subsurface. Hydraulic tomography is a viable technology to estimate the parameters in heterogeneous aquifer. [Gottlieb & Dietrich, 1995, Butler et al, 1999, Vasco et al., 2000, Yeh & Liu, 2000, Liu et al., 2002, Bohling et al., 2002, McDermott et al., 2003, Brauchler et al., 2003, Zhu & Yeh, 2005, Liu et al., 2007, Straface et al., 2007, Illman et al., 2007] 2011/3/103

4 DATA

2011/3/105

Data collection : Data collection: Cross-hole pumping test To obtain many independent pumping test data. Data integration: Data integration: Numerical inversion To integrate information of aquifer and estimate parameters. Introduction Hydraulic tomography The K tomogram 2011/3/106

Motivation 2011/3/107

Motivation 2011/3/108

packer

Changing the packer position. The field pumping test data. The limit of equipment in field test. 2011/3/1010

Objective  To conduct numerical investigations to assess how and to what degree the accuracy of the field tests for estimation. 2011/3/1011

Generation of random field Many packers, obtain data simultaneously Limited packers, obtain data sequentially A series of pumping events Numerical model Comparison of the results Methodology 2011/3/1012

Generation of random field 2011/3/1013 Mean: m/s Variance: 0.1 Correlation length: 20x5m

A series of pumping events obtain data simultaneously obtain data sequentially Numerical model 2011/3/1014

Results & Discussion 2011/3/1015

To obtain the data in each depth by changing packer position is practicable in field test. The field data we obtained are usability to estimate the spatial distribution of hydraulic properties. Conclusions 2011/3/1016

To conduct more numerical examples and insight the application for practical problem. Future work 2011/3/1017  the observation intervals  the extension of numerical boundaries  the degree of heterogeneity  the duration of sampling time

Thanks for your attention~ 2011/3/1018