Dissertation/ Thesis

Traditional Aquifer Tests: Comparing Apples to Oranges?

التفاصيل البيبلوغرافية
العنوان: Traditional Aquifer Tests: Comparing Apples to Oranges?
المؤلفون: Wu, Cheng-Mau, Yeh, Tian-Chyi J., Lee, Tim Hau, Hsu, Nein-Sheng, Chen, Chu-Hui, Sancho, Albert Folch
Thesis Advisors: Department of Hydrology & Water Resources, The University of Arizona
المصدر: Provided by the Department of Hydrology and Water Resources..
بيانات النشر: Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 2004.
سنة النشر: 2004
المجموعة: University of Arizona
مصطلحات موضوعية: pumping test, heterogeneity, drawdown-distance curve, effective hydraulic properties, REV, stochastic processes
الوصف: Traditional analysis of aquifer tests uses the observed hydrograph at one well caused by pumping at another well for estimating transmissivity and storage coefficient of an aquifer. The analysis relies on Theis' or Jacob's approximate solution, which assumes aquifer homogeneity. Aquifers are inherently heterogeneous at different scales. If the observation well taps into a low permeability zone while the pumping well is located in a high permeable zone, the resulting situation contradicts the homogeneity assumption embedded in the traditional analysis. As a result, a practical but important question we ask: What do we derive from the traditional analysis? Using numerical experiments in synthetic aquifers, we answer this question. Results of the experiments indicate that the effective transmissivity, Teff, and storage coefficient, Seff, values vary with time, as well as the principal directions of the transmissivity, but both values approach their geometric means of the aquifer at large times. Analysis of the estimated transmissivity (T) and storage coefficient (S ) using well hydrographs from a single observation well shows that at early times, both the estimated T and S values vary with time. At late times, both estimates approach local averages near the observation well. The T value approaches but does not equal Teff, representing an average value over a broad area in the vicinity of the observation well while the S value converges to the value dominated by the storage coefficient near the observation wells (i.e., its average area is much smaller than that of the t value).
Original Identifier: oai:arizona.openrepository.com:10150/615770
نوع الوثيقة: Technical Report
Relation: Technical Reports on Hydrology and Water Resources, No. 04-03
الاتاحة: http://hdl.handle.net/10150/615770
http://arizona.openrepository.com/arizona/handle/10150/615770
Rights: Copyright © Arizona Board of Regents
رقم الانضمام: edsndl.arizona.edu.oai.arizona.openrepository.com.10150.615770
قاعدة البيانات: Networked Digital Library of Theses & Dissertations