Modelling Of Downhole Seismic Sources II: An Analysis Of The Heelan/Brekhovskikh Results And Comparison Of Point Source Radiation To Radiation From Boreholes by Meredith, J. A., Cheng, C. H., Toksoz, M. N.

“…The work of Heelan (1952, 1953a,b) was one of the first studies of wave propagation from a cylindrical boundary. Heelan attempted to model the radiation emanating from a cylindrical shot hole filled with dynamite. …”
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Modeling Of Elastic Wave Propagation In A Fluid-Filled Borehole Excited By A Piezoelectric Transducer by Kostek, Sergio

“…In this paper a velocity-stress finite-difference model is presented for a cylindrical piezoelectric transducer in a borehole. …”
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Numerical Simulation Of The Acoustic And Elastic Wavefields Radiated By A Source In A Fluid-Filled Borehole Embedded In A Layered Medium by Bouchon, Michel

“…The restrictive assumptions are that the borehole is cylindrical and that its axis runs normal to the layer interfaces. …”
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The Full Waveform Acoustic Log Inversion Problem by Garcia, G. H., Cheng, C. H.

“…This paper presents the full waveform acoustic log inversion problem for a multisource - multireceiver tool logging a cylindrical fluid-filled borehole. The problem is formulated in the frequency-depth domain. …”
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Full Wave Synthetic Acoustic Logs In Saturated Porous Media Part I: A Review Of Biot's Theory by Schmitt, D. P.

“…The body wave velocities and attenuations are then computed, using the cylindrical duct model for pores. The effects of the saturant fluid, the permeability and the porosity are studied.…”
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Anisotropic Perfectly Matched Layers for Elastic Waves in Cartesian and Curvilinear Coordinates by Zheng, Yibing, Huang, Xiaojun

“…We develop new numerical anisotropic perfectly matched layer (PML) boundaries for elastic waves in Cartesian, cylindrical and spherical coordinate systems. The elasticity tensor of this absorbing boundary is chosen to be anisotropic and complex so that waves from the computational domain are attenuated in the boundary layer without reflection. …”
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Off-Center Monopole And Dipole Sources In Fluid-Filled Boreholes by Tadeu, Antonio J. B., Toksoz, M. Nafi, Kausel, Eduardo

“…In this paper, analytical-numerical solutions are used to study the wave-field elicited by monopole or dipole sources within a fluid-filled cylindrical cavity drilled through an unbounded homogeneous elastic medium. …”
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Experimental studies of streaming potential and high frequency seismoelectric conversion in porous samples by Zhu, Zhenya, Toksoz, M. Nafi, Zhan, Xin

“…In order to investigate the streaming potential and the seismoelectric conversion in the same rock sample, we conduct quantitative measurements with cylindrical and plate samples of Berea sandstone 500 saturated by NaCl solutions with different conductivities. …”
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Applications Of Perturbation Theory To Acoustic Logging by Ellefsen, K. J., Cheng, C. H.

“…The method, which is developed for a fluid-filled, cylindrical borehole through a transversely isotropic formation, relates perturbations in formation properties (i.e., elastic moduli, densities, and interface locations) and wave properties (i.e., wavenumber and frequency) for guided waves with any azimuthal order number. …”
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Guided Waves In Slight, Azimuthally Anisotropic Formations by Ellefsen, K. J., Cheng, C. H.

“…The fluid is assumed to be inviscid, the formation perfectly elastic and homogeneous, and the ·borehole wall cylindrical. The first step is calculating the elastic moduli for a transversely isotropic formation whose moduli are close to those for the azimuthally anisotropic formation. …”
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Experimental Design Applied to Borehole DC Resistivity by Coles, Darrell A., Morgan, Frank Dale

“…The borehole problem is cast in cylindrical coordinates, and because only one borehole is modeled, resistivity is treated as azimuthally invariant, permitting the problem to be treated as a form of electrical resistivity tomography. …”
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Wave Propagation In A Fluid-Filled Fracture-An Experimental Study by Tang, X. M., Cheng, C. H.

“…Using a small circular cylindrical receiver of 2.7 mm diameter, we were able to measure the wave motion directly inside a 2.8 mm thick fracture and to obtain array data for the propagating waves. …”
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Stoneley Wave Propagation In Heterogeneous Permeable Porous Formations by Zhao, Xiaomin, Toksoz, M. N., Cheng, C. H.

“…Using the theory of dynamic permeability and a finite difference technique in cylindrical coordinates, dynamic pore fluid flow in an arbitrarily heterogeneous porous medium surrounding the borehole is modeled. …”
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Transverserly Isotropic Saturated Porous Formations: 1. Theoretical Developments And (Quasi) Body Wave Properties by Schmitt, D. P.

“…The wavenumbers equations are solved as part of a cylindrical geometry and general solutions for the displacement potentials in each phase are presented. …”
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Modeling Of Seismoelectric Effects In A Borehole by Haartsen, Matthijs W., Toksoz, M. N.

“…This is necessary to calculate the element's self interaction. The borehole is cylindrical and its axis rulls normal to the interfaces. …”
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Report Summary by Cheng, C. H.

“…We have studied the diffraction of a cylindrical transducer and its effect on the measurement of attenuation in laboratory experiments using the spectral ratio technique. …”
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Theoretical Models Relating Acoustic Tube-Wave Attenuation To Fracture Permeability - Reconciling Model Results With Field Data by Cheng, C. H., Tang, X. M., Paillet, F . L.

“…Although the theory predicts some reflection from simple cylindrical passages, scattering from irregular distributions of natural fracture openings probably accounts for the infrequency with which coherent tube-wave reflections occur in field data.…”
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Effects Of Anisotropy Upon The Normal Modes by Ellefsen, K. J., Cheng, C. H., Toksoz, M. N.

“…The effects of anisotropy upon elastic wave propagation along a fluid-filled cylindrical borehole are determined. The wave equation is solved in the frequency-wavenumber domain with a variational method, and the solution yields the phase velocities, group velocities, pressures, and displacements for the normal modes. …”
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