Can storage coefficient be neglected in the estimation of unconfined aquifer parameters?

Xunhong Chen

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Unlike the Neuman solution (1974), the Dagan solution (1967) neglects elastic storage of unconfined aquifers. Whereas the former has been commonly used in the analysis of aquifer pumping tests, application of the latter to determination of aquifer parameters are rare. This article evaluates the reliability of the Dagan solution (1967) for the determination of the horizontal and vertical hydraulic conductivity Kr and Kz and specific yield Sy by neglecting the role of aquifer storage coefficient S. To be consistent in the analysis of aquifer test data, the Dagan solution was combined with an inverse computational procedure so that K r, Kz, and Sy, can be automatically calculated. Computations converge relatively fast because evaluation of the Dagan solution is mathematically simpler than is the Neuman solution. Data from three pumping tests conducted in alluvial aquifers in the Platte and Republican River valleys, Nebraska, were analyzed. Early-time drawdown data from the site in the Platte River valley are scarce, but plenty of early-time drawdowns were collected from the two sites in the Republican River valley. Comparison of the results from the Dagan and the Neuman solution indicates that the Dagan solution provides aquifer parameter values very close to those of the Neuman solution in most situations. For most practical purposes, the Dagan solution is as good as the Neuman solution for aquifer test analysis.

Original languageEnglish (US)
Pages (from-to)99-105
Number of pages7
JournalEnvironmental Geosciences
Volume7
Issue number2
DOIs
StatePublished - Jan 1 2000

Fingerprint

unconfined aquifer
aquifer
drawdown
valley
pumping
river
parameter
hydraulic conductivity
test
analysis

Keywords

  • Aquifer test
  • Hydraulic conductivity
  • Storage coefficient
  • Unconfined aquifer

ASJC Scopus subject areas

  • Environmental Science(all)
  • Earth and Planetary Sciences(all)

Cite this

Can storage coefficient be neglected in the estimation of unconfined aquifer parameters? / Chen, Xunhong.

In: Environmental Geosciences, Vol. 7, No. 2, 01.01.2000, p. 99-105.

Research output: Contribution to journalArticle

@article{c34d750544064f9dae39afe49649f70d,
title = "Can storage coefficient be neglected in the estimation of unconfined aquifer parameters?",
abstract = "Unlike the Neuman solution (1974), the Dagan solution (1967) neglects elastic storage of unconfined aquifers. Whereas the former has been commonly used in the analysis of aquifer pumping tests, application of the latter to determination of aquifer parameters are rare. This article evaluates the reliability of the Dagan solution (1967) for the determination of the horizontal and vertical hydraulic conductivity Kr and Kz and specific yield Sy by neglecting the role of aquifer storage coefficient S. To be consistent in the analysis of aquifer test data, the Dagan solution was combined with an inverse computational procedure so that K r, Kz, and Sy, can be automatically calculated. Computations converge relatively fast because evaluation of the Dagan solution is mathematically simpler than is the Neuman solution. Data from three pumping tests conducted in alluvial aquifers in the Platte and Republican River valleys, Nebraska, were analyzed. Early-time drawdown data from the site in the Platte River valley are scarce, but plenty of early-time drawdowns were collected from the two sites in the Republican River valley. Comparison of the results from the Dagan and the Neuman solution indicates that the Dagan solution provides aquifer parameter values very close to those of the Neuman solution in most situations. For most practical purposes, the Dagan solution is as good as the Neuman solution for aquifer test analysis.",
keywords = "Aquifer test, Hydraulic conductivity, Storage coefficient, Unconfined aquifer",
author = "Xunhong Chen",
year = "2000",
month = "1",
day = "1",
doi = "10.1046/j.1526-0984.2000.72006.x",
language = "English (US)",
volume = "7",
pages = "99--105",
journal = "Environmental Geosciences",
issn = "1075-9565",
publisher = "American Association of Petroleum Geologists",
number = "2",

}

TY - JOUR

T1 - Can storage coefficient be neglected in the estimation of unconfined aquifer parameters?

AU - Chen, Xunhong

PY - 2000/1/1

Y1 - 2000/1/1

N2 - Unlike the Neuman solution (1974), the Dagan solution (1967) neglects elastic storage of unconfined aquifers. Whereas the former has been commonly used in the analysis of aquifer pumping tests, application of the latter to determination of aquifer parameters are rare. This article evaluates the reliability of the Dagan solution (1967) for the determination of the horizontal and vertical hydraulic conductivity Kr and Kz and specific yield Sy by neglecting the role of aquifer storage coefficient S. To be consistent in the analysis of aquifer test data, the Dagan solution was combined with an inverse computational procedure so that K r, Kz, and Sy, can be automatically calculated. Computations converge relatively fast because evaluation of the Dagan solution is mathematically simpler than is the Neuman solution. Data from three pumping tests conducted in alluvial aquifers in the Platte and Republican River valleys, Nebraska, were analyzed. Early-time drawdown data from the site in the Platte River valley are scarce, but plenty of early-time drawdowns were collected from the two sites in the Republican River valley. Comparison of the results from the Dagan and the Neuman solution indicates that the Dagan solution provides aquifer parameter values very close to those of the Neuman solution in most situations. For most practical purposes, the Dagan solution is as good as the Neuman solution for aquifer test analysis.

AB - Unlike the Neuman solution (1974), the Dagan solution (1967) neglects elastic storage of unconfined aquifers. Whereas the former has been commonly used in the analysis of aquifer pumping tests, application of the latter to determination of aquifer parameters are rare. This article evaluates the reliability of the Dagan solution (1967) for the determination of the horizontal and vertical hydraulic conductivity Kr and Kz and specific yield Sy by neglecting the role of aquifer storage coefficient S. To be consistent in the analysis of aquifer test data, the Dagan solution was combined with an inverse computational procedure so that K r, Kz, and Sy, can be automatically calculated. Computations converge relatively fast because evaluation of the Dagan solution is mathematically simpler than is the Neuman solution. Data from three pumping tests conducted in alluvial aquifers in the Platte and Republican River valleys, Nebraska, were analyzed. Early-time drawdown data from the site in the Platte River valley are scarce, but plenty of early-time drawdowns were collected from the two sites in the Republican River valley. Comparison of the results from the Dagan and the Neuman solution indicates that the Dagan solution provides aquifer parameter values very close to those of the Neuman solution in most situations. For most practical purposes, the Dagan solution is as good as the Neuman solution for aquifer test analysis.

KW - Aquifer test

KW - Hydraulic conductivity

KW - Storage coefficient

KW - Unconfined aquifer

UR - http://www.scopus.com/inward/record.url?scp=70450085263&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=70450085263&partnerID=8YFLogxK

U2 - 10.1046/j.1526-0984.2000.72006.x

DO - 10.1046/j.1526-0984.2000.72006.x

M3 - Article

AN - SCOPUS:70450085263

VL - 7

SP - 99

EP - 105

JO - Environmental Geosciences

JF - Environmental Geosciences

SN - 1075-9565

IS - 2

ER -