Evaluation of unconfined aquifer parameters using a successive line relaxation finite difference model.

Persistent Link:
http://hdl.handle.net/10150/190992
Title:
Evaluation of unconfined aquifer parameters using a successive line relaxation finite difference model.
Author:
Rebuck, Ernest Charles,1944-
Issue Date:
1972
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
A finite difference model was developed specifically for analyzing the Grand Island, Nebraska aquifer test. Time-drawdown data for the aquifer test were fitted by least squares to an exponential type equation. To facilitate calibration of the model, interpolated distance-drawdown profiles also were fitted to an exponential type equation. The treatment of aquifer boundaries and the assumption of isotropic aquifer conditions affected the model computed water table profile. The effect was significant enough as to defy making accurate estimates of saturated hydraulic conductivity and specific yield. When the analysis was extended to long time periods of discharge, problems with the boundaries, particularly the distance to the lateral constant head boundary, led to unrealistic estimates of pumping level. The finite difference technique has its greatest application as a research method for analyzing short-duration aquifer tests provided that the aquifer conditions are well defined, measurements of pumping level are available and drawdown measurements have been secured for at least two observation wells within close proximity of the discharge well. Because of difficulties in maintaining convergence and model stability, the finite difference model reviewed in this study is too cumbersome to be considered a practical, field method for the analysis of unconfined aquifer parameters.
Type:
Dissertation-Reproduction (electronic); text
Keywords:
Hydrology.; Groundwater -- Nebraska -- Grand Island.; Groundwater -- Mathematical models.
Degree Name:
Ph. D.
Degree Level:
doctoral
Degree Program:
Hydrology and Water Resources; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Matlock, William G.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleEvaluation of unconfined aquifer parameters using a successive line relaxation finite difference model.en_US
dc.creatorRebuck, Ernest Charles,1944-en_US
dc.contributor.authorRebuck, Ernest Charles,1944-en_US
dc.date.issued1972en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractA finite difference model was developed specifically for analyzing the Grand Island, Nebraska aquifer test. Time-drawdown data for the aquifer test were fitted by least squares to an exponential type equation. To facilitate calibration of the model, interpolated distance-drawdown profiles also were fitted to an exponential type equation. The treatment of aquifer boundaries and the assumption of isotropic aquifer conditions affected the model computed water table profile. The effect was significant enough as to defy making accurate estimates of saturated hydraulic conductivity and specific yield. When the analysis was extended to long time periods of discharge, problems with the boundaries, particularly the distance to the lateral constant head boundary, led to unrealistic estimates of pumping level. The finite difference technique has its greatest application as a research method for analyzing short-duration aquifer tests provided that the aquifer conditions are well defined, measurements of pumping level are available and drawdown measurements have been secured for at least two observation wells within close proximity of the discharge well. Because of difficulties in maintaining convergence and model stability, the finite difference model reviewed in this study is too cumbersome to be considered a practical, field method for the analysis of unconfined aquifer parameters.en_US
dc.description.notehydrology collectionen_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.typetexten_US
dc.subjectHydrology.en_US
dc.subjectGroundwater -- Nebraska -- Grand Island.en_US
dc.subjectGroundwater -- Mathematical models.en_US
thesis.degree.namePh. D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineHydrology and Water Resourcesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairMatlock, William G.en_US
dc.contributor.committeememberEvans, Daniel D.en_US
dc.contributor.committeememberFangmeier, Delmar D.en_US
dc.contributor.committeememberWarrick, Arthur W.en_US
dc.identifier.oclc213091680en_US
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