Philip M. Reppert

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Frequency-Dependent Streaming Potentials Philip M. Reppert,∗,1 Frank Dale Morgan, David P. Lesmes,† and Laurence Jouniaux‡ ∗Earth Resources Laboratory, Department of Earth Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, E34-356a, 42 Carleton Street, Cambridge, Massachusetts 02142; †Department of Geology and Geophysics, Boston(More)
Ž . A method to determine ground-penetrating radar GPR velocities, which utilize Brewster angles, is presented. The method determines the relative dielectric constant ratio at interface boundaries where the radar wave is traveling from a low-velocity to a high-velocity medium. Using Brewster angle analysis is currently the only means to determine the(More)
We describe an apparatus designed to perform streaming potential and resistivity measurements on unconsolidated soil samples. The apparatus enables the use of both unidirectional and oscillatory flow methods to measure the streaming potential coupling coefficient (C); the direct current resistivity method is used to measure the bulk resistivity (rho) of the(More)
This paper presents a theory for frequency-dependent electroosmosis. It is shown that for a closed capillary the electroosmosis frequency-dependent ratio of DeltaV/DeltaP is constant with increasing frequency until inertial effects become prevalent, at which time DeltaV/DeltaP starts to decrease with increasing frequency. The frequency response of the(More)
Ground penetrating radar (GPR) signatures, such as reflection moveout, are sensitive to the presence of azimuthal anisotropy. Azimuthal anisotropy can occur as an intrinsic property of the medium and/or due to the presence of fractures. In such cases, the GPR normal moveout (NMO) velocity, along different orientations of common-midpoint (CMP) gathers,(More)
In this paper, we model frequency-dependent electro-osmosis in a capillary using the fully nonlinear Navier-Stokes equation (NSE) for viscous, incompressible, and homogeneous flow. We simulate the NSE using the finite element method, computing the solution for a closed capillary and compare it to the closed form solutions. It is confirmed that the second(More)
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