@inbook{e8343653ec974f2092734d3722d4ef6d,
title = "Geostatistical, type-curve, and inverse analyses of pneumatic injection tests in unsaturated fractured tuffs at the apache leap research site near superior, Arizona",
abstract = "Over 270 single-hole [Guzman et al., 1996] and 44 cross-hole pneumatic injection tests [Illman et al., 1998; Illman, 1999] have been conducted at the Apache Leap Research Site (ALRS) near Superior, Arizona. In this paper, we describe a geostatistical analysis of the single-hole data and type-curve as well as numerical inverse interpretations of one cross-hole test, PP4. Our geostatistical analysis yields information about the spatial structure of air permeabilities measured on a nominal scale of 1 m, as well as of other variables such as fracture density. Our type-curve and inverse interpretations of cross-hole test PP4 yield information about pneumatic connections, directional air permeabilities, and airfilled porosities on scales ranging from a few meters to a few tens of meters. The numerical model can be applied simultaneously to pressure data from multiple borehole intervals (and multiple cross-hole tests), which amounts to {"}pneumatic tomography{"} of the rock. Our analyses suggest that (a) pneumatic pressure behavior of unsaturated fractured tuffs at the ALRS can be interpreted by treating the rock as a continuum on scales ranging from meters to tens of meters; (b) this continuum is representative primarily of interconnected fractures; (c) its pneumatic properties nevertheless correlate poorly with fracture density; and (d) air permeability exhibits multiscale random variations in space.",
author = "Guoliang Chen and Illman, {Walter A.} and Thompson, {Dick L.} and Vesselinov, {Velimir V.} and Neuman, {Shlomo P.}",
note = "Funding Information: This work was supported by the U.S. Nuclear Regulatory Commission under contracts NRC-04-95-038 and NRC-04-97-056. We wish to acknowledge with gratitude the support, advice, and encouragement of our NRC Project Manager, Thomas J. Nicholson. Walter Illman was supported in part by a National Science Foundation Graduate Traineeship during 1994- 1995, a University of Arizona Graduate College Fellowship during 1997-1998, the Horton Doctoral Research Grant from the American Geophysical Union during 1997-1998, and the John and Margaret Harshbarger Doctoral Fellowship from the Department of Hydrology and Water Resources at the University of Arizona during 1998-1999. Velimir (Monty) Vesselinov conducted part of his simulation and inverse modeling work during a summer internship with the Geoanalysis Group at Los Alamos National Laboratory in 1997. We are grateful to Dr. George A. Zyvoloski for his help in the implementation of FEHM, and to Dr. Carl W. Gable for his assistance in the use of the X3D code to generate the corresponding computational grid. All pneumatic cross-hole tests at the ALRS were conducted by Walter Illman, with technical assistance by Dick Thompson. Type-curve development and analyses were performed by Walter Illman, geostatistical analyses by Guoliang Chen and Velimir Vesselinov, and the development and implementation of our inverse model by Velimir Vesselinov. We are grateful to Edwin P. Weeks and Gary D. LeCain of the U.S. Geological Survey for their constructive review of our manuscript. Funding Information: Acknowledgements. This work was supported by the U.S. Nuclear Regulatory Commission under contracts NRC-04-95-038 and NRC-04-97-056. We wish to acknowledge with gratitude the support, advice, and encouragement of our NRC Project Manager, Thomas J. Nicholson. Walter Illman was supported in part by a National Science Foundation Graduate Traineeship during 1994-1995, a University of Arizona Graduate College Fellowship during 1997-1998, the Horton Doctoral Research Grant from the American Geophysical Union during 1997-1998, and the John and Margaret Harshbarger Doctoral Fellowship from the Department of Hydrology and Water Resources at the University of Arizona during 1998-1999. Velimir (Monty) Vesselinov conducted part of his simulation and inverse modeling work during a summer internship with the Geoanalysis Group at Los Alamos National Laboratory in 1997. We are grateful to Dr. George A. Zyvoloski for his help in the implementation of FEHM, and to Dr. Carl W. Gable for his assistance in the use of the X3D code to generate the corresponding computational grid. All pneumatic cross-hole tests at the ALRS were conducted by Walter Illman, with technical assistance by Dick Thompson. Type-curve development and analyses were performed by Walter Illman, geostatistical analyses by Guoliang Chen and Velimir Vesselinov, and the development and implementation of our inverse model by Velimir Vesselinov. We are grateful to Edwin P. Weeks and Gary D. LeCain of the U.S. Geological Survey for their constructive review of our manuscript. Publisher Copyright: {\textcopyright} 2000 by the American Geophysical Union.",
year = "2000",
doi = "10.1029/GM122p0073",
language = "English (US)",
isbn = "9780875909806",
series = "Geophysical Monograph Series",
publisher = "Blackwell Publishing Ltd",
pages = "73--98",
editor = "Witherspoon, {Paul A.} and Boris Faybishenko and Benson, {Sally M.}",
booktitle = "Dynamics of Fluids in Fractured Rock, 2000",
}