In this paper, we consider an approach for estimating the effective hydraulic conductivity of a 3‐D medium with a binary distribution of local hydraulic conductivities. The medium heterogeneity is represented by a combination of matrix medium conductivity with spatially distributed sets of inclusions. Estimation of effective conductivity is based on a self‐consistent approach introduced by Shvidler [1985]. The tensor of effective hydraulic conductivity is calculated numerically by using a simple system of equations for the main diagonal elements. Verification of the method is done by comparison with theoretical results for special cases and numerical results of Desbarats [1987] and our own numerical modeling. The method was applied to estimating the effective hydraulic conductivity of a 2‐D and 3‐D fractured porous medium. The medium heterogeneity is represented by a combination of matrix conductivity and a spatially distributed set of highly conductive fractures. The tensor of effective hydraulic conductivity is calculated for parallel‐ and random‐oriented sets of fractures. The obtained effective conductivity values coincide with Romm's [1966] and Snow's [1969] theories for infinite fracture length. These values are also physically acceptable for the sparsely fractured medium case with low fracture spatial density and finite fracture length. Verification of the effective hydraulic conductivity obtained for a fractured porous medium is done by comparison with our own numerical modeling for a 3‐D case and with Malkovsky and Pek's [1995] results for a 2‐D case.

Over the last few decades, automatic sensors that record groundwater levels at high‐frequency intervals have become widely used in groundwater monitoring practice. These sensors provide large amounts of data regarding diurnal groundwater fluctuations, which can be treated as stochastic periodic time series. In this study, a simple relationship between the average standard deviation of diurnal groundwater level fluctuations and the daily evapotranspiration over relatively short periods (days or weeks) was developed for estimating groundwater consumption by phreatophytes in arid/semiarid areas. Our approach allows estimating groundwater evapotranspiration ( ) using stable statistical characteristics of diurnal groundwater fluctuations, and it is useful for analyzing large amounts of data obtained from digital groundwater level monitoring sensors. A comparison of the results from a synthetic set of groundwater level fluctuations with predefined values shows that this technique behaves consistently and is robust. A numerical analysis of one‐dimensional saturated‐unsaturated water flow to a root system using Richards' equation indicates that this method provides a reliable estimate of when the basic assumptions of the White method are met. The method was also applied to two phreatophyte‐dominated riparian sites in New Mexico to demonstrate its usefulness, which provides better results than the commonly used White method.

Nuclear transparency, T-p(A), is a measure of the average probability for a struck proton to escape the nucleus without significant re-interaction. Previously, nuclear transparencies were extracted for quasi-elastic A(e, e' p) knockout of protons with momentum below the Fermi momentum, where the spectral functions are well known. In this Letter we extract a novel observable, the transparency ratio, T-p(A)/T-p(C-12), for knockout of high-missing-momentum protons from the breakup of short-range correlated pairs (2N-SRC) in Al, Fe and Pb nuclei relative to C. The ratios were measured at momentum transfer Q(2) >= 1.5 (GeV/c)(2) and x(B) >= 1.2 where the reaction is expected to be dominated by electron scattering from 2N-SRC. The transparency ratios of the knocked-out protons coming from 2N-SRC breakup are 20-30% lower than those of previous results for low missing momentum. They agree with Glauber calculations and agree with renormalization of the previously published transparencies as proposed by recent theoretical investigations. The new transparencies scale as A(-1/3), which is consistent with dominance of scattering from nucleons at the nuclear surface. (C) 2013 Elsevier B.V. All rights reserved