A Geostatistical Inverse Method for Variably Saturated Flow in the Vadose Zone

Persistent Link:
http://hdl.handle.net/10150/614185
Title:
A Geostatistical Inverse Method for Variably Saturated Flow in the Vadose Zone
Author:
Yeh, T.-C. Jim; Zhang, Jinqi
Affiliation:
Department of Hydrology & Water Resources, The University of Arizona
Publisher:
Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ)
Issue Date:
1995-10-11
Rights:
Copyright © Arizona Board of Regents
Collection Information:
This title from the Hydrology & Water Resources Technical Reports collection is made available by the Department of Hydrology & Atmospheric Sciences and the University Libraries, University of Arizona. If you have questions about titles in this collection, please contact repository@u.library.arizona.edu.
Abstract:
A geostatistical inverse technique utilizing both primary and secondary information is developed to estimate conditional means of unsaturated hydraulic conductivity parameters (saturated hydraulic conductivity and pore -size distribution parameters) in the vadose zone. Measurements of saturated hydraulic conductivity and pore -size distribution parameters are considered as the primary information, while measurements of steady -state flow processes (soil -water pressure head and degree of saturation) are regarded as the secondary information. This inverse approach relies on the classical linear predictor (cokriging) theory and takes the advantage of the spatial cross- correlation between soil -water pressure head, degree of saturation, saturated hydraulic conductivity, and pore -size distribution parameter. Using an approximate perturbation solution for steady, variably saturated flow under general boundary conditions, the cross- covariances between the primary and secondary information are derived. The approximate solution is formulated based on a first -order Taylor series expansion of a discretized finite element equation. The sensitivity matrix in the solution is evaluated by an adjoint state sensitivity approach for flow in heterogeneous media under variably saturated conditions. Through several numerical examples, the inverse model demonstrates its ability to improve the estimates of the spatial distribution of saturated hydraulic conductivity and pore -size distribution parameters using the secondary information.
Series/Report no.:
Technical Reports on Hydrology and Water Resources, No. 95-050

Full metadata record

DC FieldValue Language
dc.contributor.authorYeh, T.-C. Jimen
dc.contributor.authorZhang, Jinqien
dc.date.accessioned2016-06-22T19:43:57Z-
dc.date.available2016-06-22T19:43:57Z-
dc.date.issued1995-10-11-
dc.identifier.urihttp://hdl.handle.net/10150/614185-
dc.description.abstractA geostatistical inverse technique utilizing both primary and secondary information is developed to estimate conditional means of unsaturated hydraulic conductivity parameters (saturated hydraulic conductivity and pore -size distribution parameters) in the vadose zone. Measurements of saturated hydraulic conductivity and pore -size distribution parameters are considered as the primary information, while measurements of steady -state flow processes (soil -water pressure head and degree of saturation) are regarded as the secondary information. This inverse approach relies on the classical linear predictor (cokriging) theory and takes the advantage of the spatial cross- correlation between soil -water pressure head, degree of saturation, saturated hydraulic conductivity, and pore -size distribution parameter. Using an approximate perturbation solution for steady, variably saturated flow under general boundary conditions, the cross- covariances between the primary and secondary information are derived. The approximate solution is formulated based on a first -order Taylor series expansion of a discretized finite element equation. The sensitivity matrix in the solution is evaluated by an adjoint state sensitivity approach for flow in heterogeneous media under variably saturated conditions. Through several numerical examples, the inverse model demonstrates its ability to improve the estimates of the spatial distribution of saturated hydraulic conductivity and pore -size distribution parameters using the secondary information.en
dc.language.isoen_USen
dc.publisherDepartment of Hydrology and Water Resources, University of Arizona (Tucson, AZ)en
dc.relation.ispartofseriesTechnical Reports on Hydrology and Water Resources, No. 95-050en
dc.rightsCopyright © Arizona Board of Regentsen
dc.sourceProvided by the Department of Hydrology and Water Resources.en
dc.titleA Geostatistical Inverse Method for Variably Saturated Flow in the Vadose Zoneen_US
dc.typetexten
dc.typeTechnical Reporten
dc.contributor.departmentDepartment of Hydrology & Water Resources, The University of Arizonaen
dc.description.collectioninformationThis title from the Hydrology & Water Resources Technical Reports collection is made available by the Department of Hydrology & Atmospheric Sciences and the University Libraries, University of Arizona. If you have questions about titles in this collection, please contact repository@u.library.arizona.edu.en
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