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University of Alberta
1.
Melendez-Martinez, Jaime.
Elastic Properties of Sedimentary Rocks.
Degree: PhD, Department of Physics, 2014, University of Alberta
URL: https://era.library.ualberta.ca/files/n009w2586
► Sedimentary rocks are an important research topic since such rocks are associated to sources of ground water as well as oil, gas, and mineral reservoirs.…
(more)
▼ Sedimentary rocks are an important research topic
since such rocks are associated to sources of ground water as well
as oil, gas, and mineral reservoirs. In this work, elastic and
physical properties of a variety of sedimentary samples that
include glacial sediments, carbonates, shales, one evaporite, and
one argillite from a variety of locations are investigated.
Assuming vertical transverse isotropy, ultrasonic compressional-
and shear-waves (at 1 MHz central frequency) were measured as a
function of confining pressure on all samples with the exception of
glacial samples which were tested assuming isotropy. Tensile
strength tests (Brazilian test) were also carried out on selected
glacial samples and, in addition, static-train measurements were
conducted on shales and argillite samples. Lithological and
textural features of samples were obtained through thin section
techniques, scanning electron microscopy images and
micro-tomography images. X-ray diffraction and X-Ray fluorescence
provided the mineralogical oxides content information. Porosity,
density, and pore structure were studied by using a mercury
intrusion porosimeter and a helium pycnometer. The wide range of
porosities of the studied samples (ranging from a minimum of 1% for
shales to a maximum 45% for some glacial sediments) influence the
measured velocities since high porosity sample shows an noticeable
velocity increment as confining pressure increases as a consequence
of closure of microcracks and pores, unlike low porosity samples
where increment is quasi-lineal. Implementation of Gassmann´s
relation to ultrasonic velocities obtained from glacial samples has
negligible impact on them when assuming water saturated samples,
which suggests that state of saturation it is no so important in
defining such velocities and instead they are mainly
frame-controlled. On the other hand, velocities measured on
carbonate and evaporite samples show that samples are at best weak
anisotropic, thus the intrinsic anisotropy of such rocks has a
minor contribution on anisotropy observed at seismic scales. In
contrast, shales and argillite samples are highly anisotropic, with
the dynamic modulus obtained from velocities up to 3.31 times
higher than static modulus obtained from static-strain measurements
at pressures <3 MPa.
Subjects/Keywords: Anisotropy; Shales
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APA (6th Edition):
Melendez-Martinez, J. (2014). Elastic Properties of Sedimentary Rocks. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/n009w2586
Chicago Manual of Style (16th Edition):
Melendez-Martinez, Jaime. “Elastic Properties of Sedimentary Rocks.” 2014. Doctoral Dissertation, University of Alberta. Accessed February 27, 2021.
https://era.library.ualberta.ca/files/n009w2586.
MLA Handbook (7th Edition):
Melendez-Martinez, Jaime. “Elastic Properties of Sedimentary Rocks.” 2014. Web. 27 Feb 2021.
Vancouver:
Melendez-Martinez J. Elastic Properties of Sedimentary Rocks. [Internet] [Doctoral dissertation]. University of Alberta; 2014. [cited 2021 Feb 27].
Available from: https://era.library.ualberta.ca/files/n009w2586.
Council of Science Editors:
Melendez-Martinez J. Elastic Properties of Sedimentary Rocks. [Doctoral Dissertation]. University of Alberta; 2014. Available from: https://era.library.ualberta.ca/files/n009w2586

Oregon State University
2.
Matusevich, David Sergio.
Magneto-crystalline anisotropy calculation in thin films with defects.
Degree: PhD, Physics, 2002, Oregon State University
URL: http://hdl.handle.net/1957/31144
► The code is developed for the calculation of the magneto-crystalline anisotropy (MAE) in thin films using a classical Heisenberg hamiltonian with a correction developed by…
(more)
▼ The code is developed for the calculation of the magneto-crystalline
anisotropy
(MAE) in thin films using a classical Heisenberg hamiltonian with a correction
developed by Van Vleck. A Metropolis style Monte Carlo algorithm was used
with adequate corrections to accelerate the calculation. The MAE was calculated
for the case of a thin film with an increasing number of defects on the top layer for
the cases where the defects were distributed randomly and when they assumed ordered
positions. The results obtained agree qualitatively with the results provided
by the literature and with the theory.
Advisors/Committee Members: Jansen, Henri J. F. (advisor).
Subjects/Keywords: Anisotropy
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APA (6th Edition):
Matusevich, D. S. (2002). Magneto-crystalline anisotropy calculation in thin films with defects. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/31144
Chicago Manual of Style (16th Edition):
Matusevich, David Sergio. “Magneto-crystalline anisotropy calculation in thin films with defects.” 2002. Doctoral Dissertation, Oregon State University. Accessed February 27, 2021.
http://hdl.handle.net/1957/31144.
MLA Handbook (7th Edition):
Matusevich, David Sergio. “Magneto-crystalline anisotropy calculation in thin films with defects.” 2002. Web. 27 Feb 2021.
Vancouver:
Matusevich DS. Magneto-crystalline anisotropy calculation in thin films with defects. [Internet] [Doctoral dissertation]. Oregon State University; 2002. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1957/31144.
Council of Science Editors:
Matusevich DS. Magneto-crystalline anisotropy calculation in thin films with defects. [Doctoral Dissertation]. Oregon State University; 2002. Available from: http://hdl.handle.net/1957/31144

Oregon State University
3.
Peery, Travis B.
A theoretical description of anisotropic chemical association and its application to hydrogen-bonded fluids.
Degree: PhD, Physics, 2003, Oregon State University
URL: http://hdl.handle.net/1957/31171
► The thermodynamic and structural effects of highly anisotropic, short-ranged attraction are investigated for single- and four-site interaction models using Wertheim's multi-density graph theory of chemical…
(more)
▼ The thermodynamic and structural effects of highly anisotropic, short-ranged
attraction are investigated for single- and four-site interaction models using
Wertheim's multi-density graph theory of chemical association. Both models consist
of associating hard spheres, where the saturable attraction sites are described
by conical wells centered in the hard core and evaluated in the "sticky-spot" limit.
The resulting fluids then mimic many of the directional and steric-constrained
properties of hydrogen-bonded fluids.
The single-site model is used to explore the effects of dimerization upon
the well-known properties of a planar liquid-vapor interface. Apart from hard
sphere repulsion and sticky-spot attraction, a van der Waals-like dispersion interaction
is incorporated to generate the critical point. Association is treated within
Wertheim's thermodynamic perturbation theory, along with classical density functional
methods to determine the interfacial density profile. The direct correlation
functions which carry all bonding information are derived by means of the
associative Ornstein-Zernike equations with a Percus-Yevick-like closure relation.
The primary effects of dimerization are manifest in system thermodynamics. Critical
temperatures and densities are shifted from their non-associating values and
small, non-monotonic shifts in the correlation length and surface tension are also
observed. While these effects are accompanied by interface compositional changes,
any influence upon the density profile seems to be subsumed by use of the proper
T/T[subscript c].
The four-site, network-forming model is investigated as a prototype for the
thermodynamics and structural properties of water. Bonding interactions occur
between "hydrogen" and electron "lone pair" sites described in the sticky-spot
limit. System properties are derived under the ideal network approximation using
the same methods as for the one-site model and are found to qualitatively reproduce
some thermodynamic and connectivity features characteristic of real water.
Partial densities are calculated self-consistently within the theory, and most thermodynamic
quantities can be written in terms of the average number of hydrogen
bonds per molecule. An analytical structure factor is also derived for this model.
Advisors/Committee Members: Evans, Glen T. (advisor), Jansen, Henri (committee member).
Subjects/Keywords: Anisotropy
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Peery, T. B. (2003). A theoretical description of anisotropic chemical association and its application to hydrogen-bonded fluids. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/31171
Chicago Manual of Style (16th Edition):
Peery, Travis B. “A theoretical description of anisotropic chemical association and its application to hydrogen-bonded fluids.” 2003. Doctoral Dissertation, Oregon State University. Accessed February 27, 2021.
http://hdl.handle.net/1957/31171.
MLA Handbook (7th Edition):
Peery, Travis B. “A theoretical description of anisotropic chemical association and its application to hydrogen-bonded fluids.” 2003. Web. 27 Feb 2021.
Vancouver:
Peery TB. A theoretical description of anisotropic chemical association and its application to hydrogen-bonded fluids. [Internet] [Doctoral dissertation]. Oregon State University; 2003. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1957/31171.
Council of Science Editors:
Peery TB. A theoretical description of anisotropic chemical association and its application to hydrogen-bonded fluids. [Doctoral Dissertation]. Oregon State University; 2003. Available from: http://hdl.handle.net/1957/31171

University of Waterloo
4.
Wang, Jingqi.
Characterization of Self-Assembling Quinoline- Based Foldamers by Fluorescence Anisotropy.
Degree: 2019, University of Waterloo
URL: http://hdl.handle.net/10012/15148
► Foldamers represent a family of synthetic macromolecules which, like their biological counterparts, are able to adopt a well-defined conformation in solution. Oligoquinoline-carboxamides (Qn) are a…
(more)
▼ Foldamers represent a family of synthetic macromolecules which, like their biological counterparts, are able to adopt a well-defined conformation in solution. Oligoquinoline-carboxamides (Qn) are a group of foldamers that adopt a helical conformation in solution. A series of Qn foldamers were prepared by chromatography-free large-scale synthesis and segment-doubling strategy. The C-terminal ester group of the Qn foldamers could be hydrolyzed to yield acid-functionalized foldamers (QnA) which could self-assemble into larger ((QnA)2-Na) complexes by metal coordination with a sodium cation. Moreover, the addition of a bis-acid functionalized tetramer (AQ2PQ2A) to a solution of (QnA)2-Na complexes resulted in insertion oligomeric products. To characterize these complexes in solution, both Qn and QnA were end-labeled with an oligo(phenylene vinylene) dye (OPV) at their N-terminus via a rigid amide bond to yield the OPV-Qn and OPV-QnA fluorescent equivalents. OPV was used to conduct time-resolved fluorescence anisotropy (TRFA) measurements on the OPV-Qn and OPV-QnA foldamers, the (OPV-QnA)2-Na complexes, and the OPV-Qn-Na-(AQ2PQ2A)n oligomers. Analysis of the TRFA of the OPV-Qn foldamers yielded the rotational time () of the fluorescent species, which was found to reflect the hydrodynamic volume (Vh) of the foldamers. The straight line obtained by plotting as a function of the number of (quinoline) units (NUs) demonstrated that the foldamers behaved in solution as rigid cylinders for all lengths examined. The linearity of the -vs-NU plot was employed as a calibration curve against which the rotational time of the QnA-complexes could be compared. Within experimental error, the rotational time of a Qn+m complex was found to equal the sum of the rotational times obtained for Qn and Qm. This result suggests that the complexation of two acid-functionalized oligoquinoline foldamers in solution generated a fully stacked foldamer with a NU equal to the sum of the NUs of its constituting elements. Hetero-complexes between OPV-Q8A and Q16A were also produced by adding a 10-fold excess of Q16A to an OPV-Q8A solution. Complexation was demonstrated by the value of the mixture, that equaled that of an OPV-Q24 foldamer. Dilution experiments on a solution of OPV-Q8A-Na-Q16A complexes led to the dissociation of the complexes into their OPV-Q8A and Q16A constituting elements, as evidenced by the progressive decrease in from the value obtained for OPV-Q24 to that of OPV-Q8 upon decreasing foldamer concentration. Similarly, the addition of increasing amounts of AQ2PQ2A to a solution of OPV-Q8A in chloroform resulted in an increase in demonstrating the formation of complexes between OPV-Q8A and AQ2PQ2A until reached a plateau for large OPV-Q8A/AQ2PQ2A molar ratios. In the plateau region, the rotational time of the oligomeric complexes generated from OPV-Q8A and AQ2PQ2A stabilized by isobutyl or hexyl side chains was equal to that of an OPV-Q¬n foldamer with n equal to 24 or 30, respectively. The apparent absence of further…
Subjects/Keywords: Fluorescence Anisotropy
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wang, J. (2019). Characterization of Self-Assembling Quinoline- Based Foldamers by Fluorescence Anisotropy. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/15148
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wang, Jingqi. “Characterization of Self-Assembling Quinoline- Based Foldamers by Fluorescence Anisotropy.” 2019. Thesis, University of Waterloo. Accessed February 27, 2021.
http://hdl.handle.net/10012/15148.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wang, Jingqi. “Characterization of Self-Assembling Quinoline- Based Foldamers by Fluorescence Anisotropy.” 2019. Web. 27 Feb 2021.
Vancouver:
Wang J. Characterization of Self-Assembling Quinoline- Based Foldamers by Fluorescence Anisotropy. [Internet] [Thesis]. University of Waterloo; 2019. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10012/15148.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wang J. Characterization of Self-Assembling Quinoline- Based Foldamers by Fluorescence Anisotropy. [Thesis]. University of Waterloo; 2019. Available from: http://hdl.handle.net/10012/15148
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
5.
MacDougall, Julia.
Lithospheric and Asthenospheric Seismic Anisotropy at
Collisional and Passive Margins.
Degree: PhD, Geological Sciences, 2014, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:386220/
► Seismic anisotropy in olivine and orthopyroxene mineral crystals enables us to infer first-order flow characteristics in the asthenospheric mantle and the preserved tectonic history in…
(more)
▼ Seismic
anisotropy in olivine and orthopyroxene
mineral crystals enables us to infer first-order flow
characteristics in the asthenospheric mantle and the preserved
tectonic history in the lithospheric mantle of continental plates.
This work focuses on the observed seismic
anisotropy within both
the lithospheric and asthenospheric mantle in the southern South
American subduction zone, the southeastern United States, and the
Hindu Kush-Pamir region. Because these three study areas represent
different tectonic environments, their patterns and sources of
seismic
anisotropy are diverse. Chapter 1 is devoted to the
observation, modeling, and interpretation of local S and
teleseismic SK(K)S shear-wave splitting results in the southern
South American subduction zone. We theorize that the observed
shear-wave splitting in the asthenospheric mantle indicates a
combination of flow through a slab gap, the presence of the flat
Pampean slab segment, and rollback of the subducting Nazca slab. In
Chapter 2, we examine the effects of those flow drivers on
asthenospheric mantle flow using a subduction zone laboratory tank
model. With this apparatus, we can replicate some of the flow
patterns discussed in Chapter 1, including the strong pull of
mantle wedge material towards the shallowly-dipping slab, analogous
to the Pampean flat slab segment. In Chapter 3, we use Pn phases
from regional earthquakes in the southeastern United States to
constrain lateral variation and azimuthal
anisotropy in uppermost
mantle P-wave velocities. In particular, mantle P-wave velocities
are significantly lower beneath the Blue Ridge Mountains,
suggesting that mantle structure may contribute to supporting the
higher elevations. We also measure azimuthal
anisotropy in this
region in Chapter 4, but here, we use S-waves to measure SK(K)S
shear-wave splitting. Because of the close station spacing and the
density of shear-wave splitting data, we are able to define
distinct lithospheric mantle
anisotropy signatures that vary
between accreted terranes. Lastly, in Chapter 5, we conduct a
shear-wave splitting study in the Hindu Kush-Pamir region, where
the SK(K)S splitting is primarily sampling asthenospheric mantle
flow induced by absolute plate motion of the Eurasian Plate. The
shallow upper plate mantle, as sampled by local S waves, is not
strongly anisotropic.
Advisors/Committee Members: Fischer, Karen (Director), Forsyth, Donald (Reader), Parman, Stephen (Reader), Parmentier, Edgar (Reader), Kincaid, Chris (Reader).
Subjects/Keywords: Seismic anisotropy
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
MacDougall, J. (2014). Lithospheric and Asthenospheric Seismic Anisotropy at
Collisional and Passive Margins. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:386220/
Chicago Manual of Style (16th Edition):
MacDougall, Julia. “Lithospheric and Asthenospheric Seismic Anisotropy at
Collisional and Passive Margins.” 2014. Doctoral Dissertation, Brown University. Accessed February 27, 2021.
https://repository.library.brown.edu/studio/item/bdr:386220/.
MLA Handbook (7th Edition):
MacDougall, Julia. “Lithospheric and Asthenospheric Seismic Anisotropy at
Collisional and Passive Margins.” 2014. Web. 27 Feb 2021.
Vancouver:
MacDougall J. Lithospheric and Asthenospheric Seismic Anisotropy at
Collisional and Passive Margins. [Internet] [Doctoral dissertation]. Brown University; 2014. [cited 2021 Feb 27].
Available from: https://repository.library.brown.edu/studio/item/bdr:386220/.
Council of Science Editors:
MacDougall J. Lithospheric and Asthenospheric Seismic Anisotropy at
Collisional and Passive Margins. [Doctoral Dissertation]. Brown University; 2014. Available from: https://repository.library.brown.edu/studio/item/bdr:386220/

Oregon State University
6.
Schneider, Gunter.
Calculation of magnetocrystalline anisotropy.
Degree: PhD, Physics, 1999, Oregon State University
URL: http://hdl.handle.net/1957/33550
► The magnetocrystalline anisotropy energy (MAE) for fcc Ni and bcc Fe is calculated as the difference of single particle energy eigenvalue sums using a tight-binding…
(more)
▼ The magnetocrystalline
anisotropy energy (MAE) for fcc Ni and bcc Fe is calculated as the difference of single particle energy eigenvalue sums using a tight-binding model. For nickel we predict a MAE of -0.15 eV and the wrong easy axis, for iron we find a MAE of -0.7 eV with the easy axis in agreement with experiment. Our results compare favorably with previously reported first-principles calculations based on density functional theory and the local spin density approximation. The inclusion of an orbital polarization correction improves the magnitude of the MAE for iron, but fails to bring the result for nickel closer to the experimental value. The outstanding feature of our calculations is the careful handling of the necessary Brillouin zone integrals. Linear interpolation schemes and methods based on Fermi surface smearing were used and analyzed. An alternative method of calculating the MAE based on the torque on a magnetic moment centered on an atom is found to be equivalent to the calculation of the MAE in terms of energy differences.
Advisors/Committee Members: Jansen, Henri J. F. (advisor).
Subjects/Keywords: Anisotropy
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
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APA (6th Edition):
Schneider, G. (1999). Calculation of magnetocrystalline anisotropy. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/33550
Chicago Manual of Style (16th Edition):
Schneider, Gunter. “Calculation of magnetocrystalline anisotropy.” 1999. Doctoral Dissertation, Oregon State University. Accessed February 27, 2021.
http://hdl.handle.net/1957/33550.
MLA Handbook (7th Edition):
Schneider, Gunter. “Calculation of magnetocrystalline anisotropy.” 1999. Web. 27 Feb 2021.
Vancouver:
Schneider G. Calculation of magnetocrystalline anisotropy. [Internet] [Doctoral dissertation]. Oregon State University; 1999. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1957/33550.
Council of Science Editors:
Schneider G. Calculation of magnetocrystalline anisotropy. [Doctoral Dissertation]. Oregon State University; 1999. Available from: http://hdl.handle.net/1957/33550

Oregon State University
7.
Thongrattanasiri, Sukosin.
Mode patterns in quadrupole resonator with anisotropic core.
Degree: MS, Physics, 2008, Oregon State University
URL: http://hdl.handle.net/1957/7606
► This thesis deals with applications of uniaxial anisotropic crystals for microcavity resonators with partially chaotic underlying ray dynamics. We develop an implementation of the scattering…
(more)
▼ This thesis deals with applications of uniaxial anisotropic crystals for microcavity resonators with partially chaotic underlying ray dynamics. We develop an implementation of the scattering matrix formalism, and relate the eigenvalues and eigenvectors of the scattering matrix to the field distribution of inside the system. Using the developed technique, we analyze the evolution of spatial structure of modes as functions of dielectric permittivities and shape of the resonator boundary. Numerical errors emanating are identified and discussed. The applications of this work lie in polarization control, negative refraction, and other optical phenomena.
Advisors/Committee Members: Podolskiy, Viktor (advisor), Jansen, Henri (committee member).
Subjects/Keywords: microcavity; Anisotropy
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Thongrattanasiri, S. (2008). Mode patterns in quadrupole resonator with anisotropic core. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/7606
Chicago Manual of Style (16th Edition):
Thongrattanasiri, Sukosin. “Mode patterns in quadrupole resonator with anisotropic core.” 2008. Masters Thesis, Oregon State University. Accessed February 27, 2021.
http://hdl.handle.net/1957/7606.
MLA Handbook (7th Edition):
Thongrattanasiri, Sukosin. “Mode patterns in quadrupole resonator with anisotropic core.” 2008. Web. 27 Feb 2021.
Vancouver:
Thongrattanasiri S. Mode patterns in quadrupole resonator with anisotropic core. [Internet] [Masters thesis]. Oregon State University; 2008. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1957/7606.
Council of Science Editors:
Thongrattanasiri S. Mode patterns in quadrupole resonator with anisotropic core. [Masters Thesis]. Oregon State University; 2008. Available from: http://hdl.handle.net/1957/7606

University of Houston
8.
Lin, Rongrong 1989-.
Extracting Polar Anisotropy Parameters from Seismic Data.
Degree: MS, Geophysics, 2013, University of Houston
URL: http://hdl.handle.net/10657/3288
► With Vp, Vs, and density well logs, we can do isotropic AVO forward modeling, using isotropic Zoeppritz equations or its approximations, and a wavelet extracted…
(more)
▼ With Vp, Vs, and density well logs, we can do isotropic AVO forward modeling, using isotropic Zoeppritz equations or its approximations, and a wavelet extracted from the seismic data, to get synthetic seismic data. Compared with real seismic data, these synthetic data are scaled differently, and ignore many propagation effects. Conventionally, the seismic data are normalized to the isotropic synthetic data for comparison; this procedure suppresses the
anisotropy information in the real data.
In this study, I tested a new method, using log data of Vp, Vs, and density, together with seismic pre-stack Common Depth Point (CDP) gathers near the well site, to deduce
anisotropy parameters from them. This dataset is from Colony Sand, Alberta, Canada. I calculated the normalization function, as in the conventional procedure, but then filtered it in frequency domain using a cut-off frequency to be determined empirically. The low-frequency part of the normalization function was used to eliminate the propagation factors in the real data, but not the reflection coefficients. After scaling, the difference between the real data, thus normalized, and the isotropic synthetic data are attributed to the anisotropic part of the reflection coefficients. The resulting distributions of and are compared to the gamma-ray log. There is a positive correlation between the
anisotropy parameter and the gamma-ray log, which is an indication of the validity of the method.
Advisors/Committee Members: Stewart, Robert R. (advisor), Thomsen, Leon (advisor), Castagna, John P. (committee member), Ebrom, Daniel A. (committee member).
Subjects/Keywords: Anisotropy; AVO
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lin, R. 1. (2013). Extracting Polar Anisotropy Parameters from Seismic Data. (Masters Thesis). University of Houston. Retrieved from http://hdl.handle.net/10657/3288
Chicago Manual of Style (16th Edition):
Lin, Rongrong 1989-. “Extracting Polar Anisotropy Parameters from Seismic Data.” 2013. Masters Thesis, University of Houston. Accessed February 27, 2021.
http://hdl.handle.net/10657/3288.
MLA Handbook (7th Edition):
Lin, Rongrong 1989-. “Extracting Polar Anisotropy Parameters from Seismic Data.” 2013. Web. 27 Feb 2021.
Vancouver:
Lin R1. Extracting Polar Anisotropy Parameters from Seismic Data. [Internet] [Masters thesis]. University of Houston; 2013. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10657/3288.
Council of Science Editors:
Lin R1. Extracting Polar Anisotropy Parameters from Seismic Data. [Masters Thesis]. University of Houston; 2013. Available from: http://hdl.handle.net/10657/3288

University of Houston
9.
-3339-6083.
Seismic Anisotropy Dependence on Fluids, Fractures, and Stress: Physical Modeling with Bakken and Barnett Shale Field Cases.
Degree: PhD, Geophysics, 2015, University of Houston
URL: http://hdl.handle.net/10657/1925
► A major goal of geophysical research is to understand and predict the seismic response of fluids, fractures, and stress in the subsurface. In this dissertation,…
(more)
▼ A major goal of geophysical research is to understand and predict the seismic response of fluids, fractures, and stress in the subsurface. In this dissertation, we explored different forward modeling and field techniques with the goal of quantifying seismic
anisotropy and its relationship with subsurface states. This dissertation includes two series of physical modeling experiments as well as analyses of wide-azimuth 3D data from the Williston Basin in North Dakota and the Fort Worth Basin in Texas. In the first set of lab experiments, we explored fluid substitution effects in a synthetic anisotropic medium. We observed the effects of different fluids on wide-azimuth P-wave NMO ellipses from our synthetic composite rock sample. We find that fluid substitution from air to water can increase inherent anisotropies by as much as 50%. We also observe changes in P-wave NMO ellipses as a function of different fluid saturants in the synthetic sample. In the second set of experiments, we varied uniaxial normal stress and measured transit-time and its associated effects on a layered synthetic orthorhombic medium. The experiment was designed to measure the dynamic elastic properties of sedimentary reservoir rocks deposited in layers under stress. Results show a general increase in all measured velocities with stress ranging from 4% to 10%. We also observed anisotropic behavior a priori to both orthorhombic and VTI symmetries in different principal axes of the synthetic sample as uniaxial stress changes. 3D wide-azimuth data from the Ross Field of the Williston Basin in North Dakota is fully processed using conventional techniques. We presented a velocity-based workflow for inverting for the direction and intensity of preferred orientations within the subsurface. We demonstrate a potential for using wide-azimuth P-wave seismic data as a tool for subsurface characterization in shale reservoirs. Lastly, using fully processed wide-azimuth 3D dataset and wells from the Fort Worth Basin in Texas, we presented a workflow that integrated RMO analysis and azimuthally sectored inversions to generate a broad overview of subsurface orientation in the Barnett shale play.
Advisors/Committee Members: Stewart, Robert R. (advisor), Chesnokov, Evgeni M. (committee member), Zheng, Yingcai (committee member), Peterson, Steven (committee member).
Subjects/Keywords: Seismology; Anisotropy
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APA (6th Edition):
-3339-6083. (2015). Seismic Anisotropy Dependence on Fluids, Fractures, and Stress: Physical Modeling with Bakken and Barnett Shale Field Cases. (Doctoral Dissertation). University of Houston. Retrieved from http://hdl.handle.net/10657/1925
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Chicago Manual of Style (16th Edition):
-3339-6083. “Seismic Anisotropy Dependence on Fluids, Fractures, and Stress: Physical Modeling with Bakken and Barnett Shale Field Cases.” 2015. Doctoral Dissertation, University of Houston. Accessed February 27, 2021.
http://hdl.handle.net/10657/1925.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
MLA Handbook (7th Edition):
-3339-6083. “Seismic Anisotropy Dependence on Fluids, Fractures, and Stress: Physical Modeling with Bakken and Barnett Shale Field Cases.” 2015. Web. 27 Feb 2021.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Vancouver:
-3339-6083. Seismic Anisotropy Dependence on Fluids, Fractures, and Stress: Physical Modeling with Bakken and Barnett Shale Field Cases. [Internet] [Doctoral dissertation]. University of Houston; 2015. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10657/1925.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Council of Science Editors:
-3339-6083. Seismic Anisotropy Dependence on Fluids, Fractures, and Stress: Physical Modeling with Bakken and Barnett Shale Field Cases. [Doctoral Dissertation]. University of Houston; 2015. Available from: http://hdl.handle.net/10657/1925
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

University of British Columbia
10.
Yedlin, Mathew Jacob.
Disk ray theory in transversely isotropic media.
Degree: PhD, Astronomy, 1978, University of British Columbia
URL: http://hdl.handle.net/2429/21324
► The first motion approximation has been used to calculate synthetic seisnograms in transversely isotropic, linear, elastic media. To achieve this end the equations of motion…
(more)
▼ The first motion approximation has been used to calculate synthetic seisnograms in transversely isotropic, linear, elastic media. To achieve this end the equations of motion have been solved in a geometrical optics regime. Formally, this has been accomplished by the use of asymptotic propagator matrices. This formalism is important, since the phase of the JWKB reflection coefficient can be easily calculated by consideration of the radiation condition. Calculation of this reflection coefficient has shown that the turning point behaviour is identical to that obtained for an isotropic medium. The similarity of the turning point behaviour is a direct consequence of the physical result that at a turning point the phase and group velocities are in the same direction.
To understand the results of the first motion approximation applied to a simple upper mantle model, it is first necessary to understand the basic physics of transversely isotropic media. This has been achieved by examination of the dispersion relation arising from Newton*s Laws for an elastic solid. From the dispersion relation, it has been demonstrated how the Green's Function can be constructed using elementary projective geometry. Subsequently, the nature of the Green's Function has been analyzed. The analysis of the Green's Function (wave
surface) is important because it facilitates comprehension of any dynamical results.
The synthetic seismograms were calculated using ray parameter versus distance curves. These curves were obtained by integration of the ray equations derived form the dispersion relations. A Gaussian-Kantorovich method was utilized to perform the required integration. This hybrid integration technique proved to be extremely fast and accurate. When the resulting p-delta curve was used to calculate the synthetic seismogram, the main effect of the anisotropic model considered was a kinematic one - the main arrivals were earlier than those for an isotropic model.
Subjects/Keywords: Anisotropy
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Chicago ·
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APA (6th Edition):
Yedlin, M. J. (1978). Disk ray theory in transversely isotropic media. (Doctoral Dissertation). University of British Columbia. Retrieved from http://hdl.handle.net/2429/21324
Chicago Manual of Style (16th Edition):
Yedlin, Mathew Jacob. “Disk ray theory in transversely isotropic media.” 1978. Doctoral Dissertation, University of British Columbia. Accessed February 27, 2021.
http://hdl.handle.net/2429/21324.
MLA Handbook (7th Edition):
Yedlin, Mathew Jacob. “Disk ray theory in transversely isotropic media.” 1978. Web. 27 Feb 2021.
Vancouver:
Yedlin MJ. Disk ray theory in transversely isotropic media. [Internet] [Doctoral dissertation]. University of British Columbia; 1978. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/2429/21324.
Council of Science Editors:
Yedlin MJ. Disk ray theory in transversely isotropic media. [Doctoral Dissertation]. University of British Columbia; 1978. Available from: http://hdl.handle.net/2429/21324

NSYSU
11.
Wang, Hsian-jen.
Magnetic domain evolution in nanoscale disk.
Degree: Master, Physics, 2009, NSYSU
URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0713109-185824
► Magnetism is one of material essential attributes, the different materialâs magnetic has been studied for many years as well as the application.The processing is smaller…
(more)
▼ Magnetism is one of material essential attributes, the different materialâs magnetic has been studied for many years as well as the application.The processing is smaller with recent years, and the submicro physical phenomenon adapt to more and more important. Microscopically, ferromagnetic material tend to reduce the total energy of the system, and the sample interior will response to devide several magnetic domains, however, from the article by G. Leaf et al[34], we saw the final domain structure at remanence of cobalt bar, which is not the configuration with lowest energy, is predicted from a high-field analysis of the frequencies of the standing spin waves. To further discuss this interesting phenomenon, we use the computer simulation method, and make a series of computation of cobalt disc with the various sizes and thickness. From this research, we will propose that the magnetic domain reverse process and mechanism, and also give showing relations to between the energy and the magnetic
domain.
Advisors/Committee Members: Wen-Ching Lin (chair), Chien-Cheng Kuo (committee member), Feng-Chuan Chuang (chair), Wang-Chi Yeh (chair).
Subjects/Keywords: Anisotropy; Domain; Cobalt
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Wang, H. (2009). Magnetic domain evolution in nanoscale disk. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0713109-185824
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wang, Hsian-jen. “Magnetic domain evolution in nanoscale disk.” 2009. Thesis, NSYSU. Accessed February 27, 2021.
http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0713109-185824.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wang, Hsian-jen. “Magnetic domain evolution in nanoscale disk.” 2009. Web. 27 Feb 2021.
Vancouver:
Wang H. Magnetic domain evolution in nanoscale disk. [Internet] [Thesis]. NSYSU; 2009. [cited 2021 Feb 27].
Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0713109-185824.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wang H. Magnetic domain evolution in nanoscale disk. [Thesis]. NSYSU; 2009. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0713109-185824
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Wayne State University
12.
Watling, Brittany.
Seismic Anisotropy As A Function Of Mineralogy And Rock Type In Chester Gneiss Dome, Southeast Vermont.
Degree: MS, Geology, 2017, Wayne State University
URL: https://digitalcommons.wayne.edu/oa_theses/593
► Our knowledge of composition and structure in middle and lower crustal rocks is limited due to restricted accessibility, and thus comes mainly from studies…
(more)
▼ Our knowledge of composition and structure in middle and lower crustal rocks is limited due to restricted accessibility, and thus comes mainly from studies of seismic velocities. But isotropic seismic velocities are not sufficient to distinguish between the many possible rock types in the middle and lower crust. Seismic
anisotropy is the directional dependence of seismic velocity, and may provide further constraints on mineralogy and rock type. This study is focused on characterizing the seismic
anisotropy of rocks from the Chester dome in southeast Vermont. We have simplified the Chester dome rock types into four groups based on rock type and composition: gneisses (felsic (7) and mafic (4)), and schists (felsic (5) and mafic (5)). We calculated elastic tensors from electron backscatter diffraction (EBSD) measurements of mineral crystallographic preferred orientations. Results show that gneiss Vp
anisotropy (AVp) ranges 4.0-14.8% and schist AVp ranges from 9.2-25.1%. On average, the mafic gneiss samples are slightly more anisotropic than the felsic gneiss but the felsic schist samples are more anisotropic than the mafic schist. Both mineralogy and rock type are important for controlling elastic properties, and thus seismic
anisotropy has the potential for distinguishing between different rock types, and similar rock types with different mineralogy.
Advisors/Committee Members: Sarah Brownlee.
Subjects/Keywords: seismic anisotropy; Geology
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APA (6th Edition):
Watling, B. (2017). Seismic Anisotropy As A Function Of Mineralogy And Rock Type In Chester Gneiss Dome, Southeast Vermont. (Masters Thesis). Wayne State University. Retrieved from https://digitalcommons.wayne.edu/oa_theses/593
Chicago Manual of Style (16th Edition):
Watling, Brittany. “Seismic Anisotropy As A Function Of Mineralogy And Rock Type In Chester Gneiss Dome, Southeast Vermont.” 2017. Masters Thesis, Wayne State University. Accessed February 27, 2021.
https://digitalcommons.wayne.edu/oa_theses/593.
MLA Handbook (7th Edition):
Watling, Brittany. “Seismic Anisotropy As A Function Of Mineralogy And Rock Type In Chester Gneiss Dome, Southeast Vermont.” 2017. Web. 27 Feb 2021.
Vancouver:
Watling B. Seismic Anisotropy As A Function Of Mineralogy And Rock Type In Chester Gneiss Dome, Southeast Vermont. [Internet] [Masters thesis]. Wayne State University; 2017. [cited 2021 Feb 27].
Available from: https://digitalcommons.wayne.edu/oa_theses/593.
Council of Science Editors:
Watling B. Seismic Anisotropy As A Function Of Mineralogy And Rock Type In Chester Gneiss Dome, Southeast Vermont. [Masters Thesis]. Wayne State University; 2017. Available from: https://digitalcommons.wayne.edu/oa_theses/593

Colorado State University
13.
Solomon, Melinda A.
Using waveform modeling of seismic anisotropy to understand the process of Proterozoic lithospheric assembly.
Degree: MS(M.S.), Geosciences, 2013, Colorado State University
URL: http://hdl.handle.net/10217/79186
► In this study, SKS data from two long-standing broadband seismic stations located along the Proterozoic Trans Hudson Orogen is analyzed for the effects of complex…
(more)
▼ In this study, SKS data from two long-standing broadband seismic stations located along the Proterozoic Trans Hudson Orogen is analyzed for the effects of complex
anisotropy. The Trans Hudson Orogen is the lasting expression of collisional events that brought together Archean continental fragments to form the cratonic core of the North American continent. Split SKS waveforms observed at two GSN stations, FFC located on the Sask craton near Flin Flon, Manitoba, and RSSD located on the eastern margin of the Wyoming craton in the Black Hills of South Dakota, are analyzed for anisotropic layering of varying complexity. At FFC we find that a model with two flat layers of
anisotropy is better able to explain the data than the simple model of one flat layer. A top layer shows
anisotropy perpendicular to the convergence direction of the Trans Hudson Orogen that is similar to observations of
anisotropy today at convergent margins, and is attributed to lithospheric deformation during convergence. RSSD shows more complex splitting that we interpret as sub-wavelength scale anisotropic heterogeneity resulting from convergence driven fragmentation of the pre-existing lithosphere into small, < ~40 km pieces. Previous studies show more coherent
anisotropy to the east and west of RSSD, suggesting that anisotropic heterogeneity here is related to the convergence, and may be a longstanding feature of tectonic boundaries.
Advisors/Committee Members: Schutt, Derek L. (advisor), Harry, Dennis (committee member), Hannah, Judy (committee member), Breidt, Jay (committee member).
Subjects/Keywords: anisotropy; SKS; seismology
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Solomon, M. A. (2013). Using waveform modeling of seismic anisotropy to understand the process of Proterozoic lithospheric assembly. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/79186
Chicago Manual of Style (16th Edition):
Solomon, Melinda A. “Using waveform modeling of seismic anisotropy to understand the process of Proterozoic lithospheric assembly.” 2013. Masters Thesis, Colorado State University. Accessed February 27, 2021.
http://hdl.handle.net/10217/79186.
MLA Handbook (7th Edition):
Solomon, Melinda A. “Using waveform modeling of seismic anisotropy to understand the process of Proterozoic lithospheric assembly.” 2013. Web. 27 Feb 2021.
Vancouver:
Solomon MA. Using waveform modeling of seismic anisotropy to understand the process of Proterozoic lithospheric assembly. [Internet] [Masters thesis]. Colorado State University; 2013. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10217/79186.
Council of Science Editors:
Solomon MA. Using waveform modeling of seismic anisotropy to understand the process of Proterozoic lithospheric assembly. [Masters Thesis]. Colorado State University; 2013. Available from: http://hdl.handle.net/10217/79186

Colorado School of Mines
14.
Kamath, Nishant.
Full-waveform inversion in 2D VTI media.
Degree: PhD, Geophysics, 2016, Colorado School of Mines
URL: http://hdl.handle.net/11124/170111
► Full-waveform inversion (FWI) is a technique designed to produce a high-resolution model of the subsurface by using information contained in entire seismic waveforms. This thesis…
(more)
▼ Full-waveform inversion (FWI) is a technique designed to produce a high-resolution model of the subsurface by using information contained in entire seismic waveforms. This thesis presents a methodology for FWI in elastic VTI (transversely isotropic with a vertical axis of symmetry) media and discusses synthetic results for heterogeneous VTI models. First, I develop FWI for multicomponent data from a horizontally layered VTI model. The reflectivity method, which permits computation of only PP reflections or a combination of PP and PSV events, is employed to model the data. The Gauss-Newton technique is used to invert for the interval Thomsen parameters, while keeping the densities fixed at the correct values. Eigenval- ue/eigenvector decompostion of the Hessian matrix helps analyze the sensitivity of the objective function to the model parameters. Whereas PP data alone are generally sufficient to constrain all four Thomsen parameters even for conventional spreads, including PS reflections provides better constraints, especially for the deeper part of the model. Next, I derive the gradients of the FWI objective function with respect to the stiffness coef- ficients of arbitrarily anisotropic media by employing the adjoint-state method. From these ex- pressions, it is straightforward to compute the gradients for parameters of 2D heterogeneous VTI media. FWI is implemented in the time domain with the steepest-descent method used to itera- tively update the model. The algorithm is tested on transmitted multicomponent data generated for Gaussian anomalies in Thomsen parameters embedded in homogeneous VTI media. To test the sensitivity of the objective function to different model parameters, I derive an an- alytic expression for the Fr ́echet kernel of FWI for arbitrary anisotropic symmetry by using the Born approximation and asymptotic Green’s functions. The amplitude of the kernel, which repre- sents the radiation pattern of a secondary source (that source describes a perturbation in a model parameter), yields the angle-dependent energy scattered by the perturbation. Then the radiation patterns are obtained for anomalies in VTI parameters embedded in isotropic homogeneous media and employed to analyze the inversion results for the transmission FWI experiments. To understand some of the challenges posed by data recorded in surface surveys, I generate the multicomponent wavefield for a model based on a geologic section of the Valhall Field in the North Sea. A multiscale approach is adopted to perform FWI in the time domain. For the available offset range, diving-wave energy illuminates the top 1.5 km of the section, with the updates in the deeper regions due primarily to the reflections. FWI is tested for three model parameterizations and the results are explained in terms of the P- and SV-radiation patterns described above. These parameterizations lead to different trade-offs, and the choice of parameterization for a given data set depends on the recorded offset range, the quality of the initial model, and the parameter…
Advisors/Committee Members: TSvankin, I. D. (advisor), Hale, Dave, 1955- (committee member), Krahenbuhl, Richard A. (committee member), Tutuncu, Azra (committee member), Tenorio, Luis (committee member).
Subjects/Keywords: anisotropy; elastic; inversion
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kamath, N. (2016). Full-waveform inversion in 2D VTI media. (Doctoral Dissertation). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/170111
Chicago Manual of Style (16th Edition):
Kamath, Nishant. “Full-waveform inversion in 2D VTI media.” 2016. Doctoral Dissertation, Colorado School of Mines. Accessed February 27, 2021.
http://hdl.handle.net/11124/170111.
MLA Handbook (7th Edition):
Kamath, Nishant. “Full-waveform inversion in 2D VTI media.” 2016. Web. 27 Feb 2021.
Vancouver:
Kamath N. Full-waveform inversion in 2D VTI media. [Internet] [Doctoral dissertation]. Colorado School of Mines; 2016. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/11124/170111.
Council of Science Editors:
Kamath N. Full-waveform inversion in 2D VTI media. [Doctoral Dissertation]. Colorado School of Mines; 2016. Available from: http://hdl.handle.net/11124/170111

King Abdullah University of Science and Technology
15.
Zhan, Ge.
Reverse-time Migration in Tilted Transversely Isotropic Media with Decoupled Equations.
Degree: Physical Science and Engineering (PSE) Division, 2012, King Abdullah University of Science and Technology
URL: http://hdl.handle.net/10754/266172
► Conventional modeling and migration for tilted transversely isotropic (TTI) media may suffer from numerical instabilities and shear wave artifacts due to the coupling of the…
(more)
▼ Conventional modeling and migration for tilted transversely isotropic (TTI) media may suffer from numerical instabilities and shear wave artifacts due to the coupling of the P-wave and SV-wave modes in the TTI coupled equations. Starting with the separated P- and SV-phase velocity expressions for vertical transversely isotropic (VTI) media, I extend these decoupled equations for modeling and reverse-time migration (RTM) in acoustic TTI media. Compared with the TTI coupled equations published in the geophysical literature, the new TTI decoupled equations provide a more stable solution due to the complete separation of the P-wave and SV-wave modes. The pseudospectral (PS) method is the most convenient method to implement these equations due to the form of wavenumber expressions and has the added benefit of being highly accurate and thus avoiding numerical dispersion. The rapid expansion method (REM) in time is employed to produce a broad band numerically stable time evolution of the wavefields. Synthetic results validate the proposed TTI decoupled equations and show that modeling and RTM in TTI media with the decoupled P-wave equation remain numerically stable even for models with strong
anisotropy and sharp contrasts.
The most desirable feature of the TTI decoupled P-wave equation is that it is absolutely free of shear-wave artifacts and the consequent alleviation of numerical instabilities generally suffered by some systems of coupled equations. However, due to several forward-backward Fourier transforms in wavefield extrapolation at each time step, the computational cost is also high, and thereby hampers its prevalence. I hereby propose to use a hybrid pseudospectral and finite-difference (FD) scheme to solve the TTI decoupled P-wave equation. In the hybrid solution, most of the cost-consuming wavenumber terms in the equation are replaced by inexpensive FD operators, which in turn accelerates the computation and reduces the computational cost. To demonstrate the benefit in cost saving of the new scheme, 2D and 3D RTM examples using the hybrid solution to the decoupled P-wave equation are carried out, and respective runtimes are listed and compared. Computation examples show that the hybrid strategy demands less computation time and is faster than using the pseudospectral method alone. Furthermore, this new hybrid TTI RTM algorithm is less computationally expensive than the FD solution to the conventional TTI coupled equations but more stable.
Advisors/Committee Members: Schuster, Gerard T. (advisor), Stoffa, Paul L. (committee member), Sun, Shuyu (committee member), Wu, Ying (committee member).
Subjects/Keywords: Seismic; Anisotropy; Migration
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zhan, G. (2012). Reverse-time Migration in Tilted Transversely Isotropic Media with Decoupled Equations. (Thesis). King Abdullah University of Science and Technology. Retrieved from http://hdl.handle.net/10754/266172
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Zhan, Ge. “Reverse-time Migration in Tilted Transversely Isotropic Media with Decoupled Equations.” 2012. Thesis, King Abdullah University of Science and Technology. Accessed February 27, 2021.
http://hdl.handle.net/10754/266172.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zhan, Ge. “Reverse-time Migration in Tilted Transversely Isotropic Media with Decoupled Equations.” 2012. Web. 27 Feb 2021.
Vancouver:
Zhan G. Reverse-time Migration in Tilted Transversely Isotropic Media with Decoupled Equations. [Internet] [Thesis]. King Abdullah University of Science and Technology; 2012. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10754/266172.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zhan G. Reverse-time Migration in Tilted Transversely Isotropic Media with Decoupled Equations. [Thesis]. King Abdullah University of Science and Technology; 2012. Available from: http://hdl.handle.net/10754/266172
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Oregon State University
16.
Anantanasakul, Pongpipat.
Three-dimensional experiments and modeling of anisotropic clay.
Degree: PhD, Civil Engineering, 2010, Oregon State University
URL: http://hdl.handle.net/1957/18834
► This dissertation presents the results of a research effort conducted to better understand the stress-strain, volume change, shear band formation, and strength characteristics of normally…
(more)
▼ This dissertation presents the results of a research effort conducted to better understand the stress-strain, volume change, shear band formation, and strength characteristics of normally consolidated anisotropic clay under fully three-dimensional stress states. A series of consolidated drained true triaxial tests with a constant mean effective stress and constant Lode angles during shear are performed on cross-anisotropic kaolin clay. All tests are performed in a fully automated true triaxial testing apparatus. The relative magnitude of the intermediate principal stress, expressed in terms of the b-value, and initial cross-
anisotropy show significant influence on the stress-strain, volume change, strength, and shear band formation characteristics of the clay. Shear bands form and appear to cause failure in all true triaxial tests performed, except in triaxial compression. The initiation and development of shear bands is observed to take place when the clay undergoes volumetric contraction. The lower strength exhibited in the shear bands is caused by alignment of the clay particles. This shear band mechanism is different from that observed in granular materials in which the lower shear strength is reached due to dilation in the shear bands.
This dissertation also presents a study on the simulative capabilities of anisotropic and isotropic elasto-plastic bounding surface models under fully three-dimensional stresses. The models assume the associated plastic flow rule and are based on bounding surface elastoplasticity and the critical state theory. The predictions of the models are compared to the stress-strain, volume change, and strength characteristics observed in drained true triaxial tests with a constant effective mean stress and constant Lode angles during shear on normally consolidated anisotropic kaolin clay. The bounding surface models can predict the influence of intermediate principal stress on the behavior of the clay but with magnitudes considerably different from those observed in the experimental results. The effects of initial cross-
anisotropy on the behavior of the clay, however, cannot be fully predicted by the anisotropic bounding surface model. These incapabilities are largely due to the use of associated plastic flow rule. More realistic predictions can also be obtained by incorporating a model feature that allows bifurcation from the uniform stress-strain conditions into a localized failure mode or shear bands.
This dissertation also includes the details and results of a laboratory study on the influence of non-plastic silt content on the stress-strain, volume change, and strength characteristics of transition silt-clay soils. Series of one-dimensional consolidation tests, isotropic consolidation tests, and triaxial compression tests on three soils of similar base clay but different non-plastic silt contents are performed on cross-anisotropic specimens. The specimen preparation method, testing procedure, and testing conditions of each testing type are controlled to be consistent. Both…
Advisors/Committee Members: Ashford, Scott A. (advisor), Lade, Poul V. (committee member).
Subjects/Keywords: anisotropy; Clay soils – Testing
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Anantanasakul, P. (2010). Three-dimensional experiments and modeling of anisotropic clay. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/18834
Chicago Manual of Style (16th Edition):
Anantanasakul, Pongpipat. “Three-dimensional experiments and modeling of anisotropic clay.” 2010. Doctoral Dissertation, Oregon State University. Accessed February 27, 2021.
http://hdl.handle.net/1957/18834.
MLA Handbook (7th Edition):
Anantanasakul, Pongpipat. “Three-dimensional experiments and modeling of anisotropic clay.” 2010. Web. 27 Feb 2021.
Vancouver:
Anantanasakul P. Three-dimensional experiments and modeling of anisotropic clay. [Internet] [Doctoral dissertation]. Oregon State University; 2010. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1957/18834.
Council of Science Editors:
Anantanasakul P. Three-dimensional experiments and modeling of anisotropic clay. [Doctoral Dissertation]. Oregon State University; 2010. Available from: http://hdl.handle.net/1957/18834

Universiteit Utrecht
17.
Beyeler, K.K.
Detect clustering in cells using Homo-FRET.
Degree: 2015, Universiteit Utrecht
URL: http://dspace.library.uu.nl:8080/handle/1874/323190
► In this research homo-FRET was used to detect clustering of EGFR in cells. To test this method reference constructs were made containing (2x)FKBP. A wide…
(more)
▼ In this research homo-FRET was used to detect clustering of EGFR in cells. To test this method
reference constructs were made containing (2x)FKBP. A wide field microscope, polarizing beamsplitter
and two cameras where used to detect polarizations. As a labeling fluorophore mCherry was
used instead of the common mGFP because the autofluorescence is believed to be lower in the red
spectrum. The best result obtained so far is a drop of 7.8 ± 6.8% in the case of FKBP and 11.3 ±
6.1% in the case of 2xFKBP upon adding AP. EGFR samples where also stimulated with EGF but
a significant drop was not observed yet. The main problem encountered was registrating the two
images.
Advisors/Committee Members: Blab, Gerhard, Imhof, Arnout.
Subjects/Keywords: Homo-FRET FRET anisotropy FKBP
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APA (6th Edition):
Beyeler, K. K. (2015). Detect clustering in cells using Homo-FRET. (Masters Thesis). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/323190
Chicago Manual of Style (16th Edition):
Beyeler, K K. “Detect clustering in cells using Homo-FRET.” 2015. Masters Thesis, Universiteit Utrecht. Accessed February 27, 2021.
http://dspace.library.uu.nl:8080/handle/1874/323190.
MLA Handbook (7th Edition):
Beyeler, K K. “Detect clustering in cells using Homo-FRET.” 2015. Web. 27 Feb 2021.
Vancouver:
Beyeler KK. Detect clustering in cells using Homo-FRET. [Internet] [Masters thesis]. Universiteit Utrecht; 2015. [cited 2021 Feb 27].
Available from: http://dspace.library.uu.nl:8080/handle/1874/323190.
Council of Science Editors:
Beyeler KK. Detect clustering in cells using Homo-FRET. [Masters Thesis]. Universiteit Utrecht; 2015. Available from: http://dspace.library.uu.nl:8080/handle/1874/323190

University of Alberta
18.
Umezawa, Ado.
Magnetic anisotropy in the high transition temperature
superconductor YBa2Cu3O7-[delta].
Degree: PhD, Department of Physics, 1991, University of Alberta
URL: https://era.library.ualberta.ca/files/mk61rk15g
Subjects/Keywords: Anisotropy.; Superconductors.
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Umezawa, A. (1991). Magnetic anisotropy in the high transition temperature
superconductor YBa2Cu3O7-[delta]. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/mk61rk15g
Chicago Manual of Style (16th Edition):
Umezawa, Ado. “Magnetic anisotropy in the high transition temperature
superconductor YBa2Cu3O7-[delta].” 1991. Doctoral Dissertation, University of Alberta. Accessed February 27, 2021.
https://era.library.ualberta.ca/files/mk61rk15g.
MLA Handbook (7th Edition):
Umezawa, Ado. “Magnetic anisotropy in the high transition temperature
superconductor YBa2Cu3O7-[delta].” 1991. Web. 27 Feb 2021.
Vancouver:
Umezawa A. Magnetic anisotropy in the high transition temperature
superconductor YBa2Cu3O7-[delta]. [Internet] [Doctoral dissertation]. University of Alberta; 1991. [cited 2021 Feb 27].
Available from: https://era.library.ualberta.ca/files/mk61rk15g.
Council of Science Editors:
Umezawa A. Magnetic anisotropy in the high transition temperature
superconductor YBa2Cu3O7-[delta]. [Doctoral Dissertation]. University of Alberta; 1991. Available from: https://era.library.ualberta.ca/files/mk61rk15g

University of Michigan
19.
Knoll, Glenn F.
Scintillation anisotropy in crystalline anthracene.
Degree: 1969, University of Michigan
URL: http://hdl.handle.net/2027.42/6892
Subjects/Keywords: Anisotropy.; Engineering
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Knoll, G. F. (1969). Scintillation anisotropy in crystalline anthracene. (Thesis). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/6892
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Knoll, Glenn F. “Scintillation anisotropy in crystalline anthracene.” 1969. Thesis, University of Michigan. Accessed February 27, 2021.
http://hdl.handle.net/2027.42/6892.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Knoll, Glenn F. “Scintillation anisotropy in crystalline anthracene.” 1969. Web. 27 Feb 2021.
Vancouver:
Knoll GF. Scintillation anisotropy in crystalline anthracene. [Internet] [Thesis]. University of Michigan; 1969. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/2027.42/6892.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Knoll GF. Scintillation anisotropy in crystalline anthracene. [Thesis]. University of Michigan; 1969. Available from: http://hdl.handle.net/2027.42/6892
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Georgia Tech
20.
Restrepo Florez, Juan Manuel.
Exploring metamaterials for the control of mass diffusion.
Degree: PhD, Chemical and Biomolecular Engineering, 2019, Georgia Tech
URL: http://hdl.handle.net/1853/62685
► In this work we have explored the use of metamaterials theory for the design of materials and devices able to control mass diffusion at will.…
(more)
▼ In this work we have explored the use of metamaterials theory for the design of materials and devices able to control mass diffusion at will. First, we focus in the design of metamaterials able to control the diffusion of a single chemical species (Chapters 3-4). In this first part we establish the use of coordinate transformation techniques to obtain benchmark metamaterials (cloaks and concentrators), we explore the design space for these devices, and establish a proper effective medium framework allowing the realization of mass diffusion metamaterials. In the second part of this work we extend our findings to the design of devices able to control simultaneously and independently the flux trajectory of two arbitrary chemical species (Chapters 5-6). These metamaterial devices are able to sort chemical species by sending molecules toward opposite places. Finally, in the third part of this work we study the use of tailored anisotropic materials (metamaterials) in the contexts of membrane based gas separations (Chapters 7-10). In this part we show how metamaterial membranes operate different than typical isotropic materials generating at least two permeate fractions instead of one. We also show how the use of anisotropic materials can significantly increase the selectivity in membrane separation processes, importantly this increase in selectivity occurs at the expense of reducing the collection area on the permeate site. The study and characterization of anisotropic membranes in the context of membrane separations is a new area, we believe that this new kind of materials may pave the way toward the design of new separation processes and to reconceive existing ones.
Advisors/Committee Members: Maldovan, Martin (advisor), Sholl, David S. (committee member), Jones, Christopher W. (committee member), Lively, Ryan P. (committee member).
Subjects/Keywords: Metamaterials; Membrane separations; Anisotropy; Diffusion
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Restrepo Florez, J. M. (2019). Exploring metamaterials for the control of mass diffusion. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/62685
Chicago Manual of Style (16th Edition):
Restrepo Florez, Juan Manuel. “Exploring metamaterials for the control of mass diffusion.” 2019. Doctoral Dissertation, Georgia Tech. Accessed February 27, 2021.
http://hdl.handle.net/1853/62685.
MLA Handbook (7th Edition):
Restrepo Florez, Juan Manuel. “Exploring metamaterials for the control of mass diffusion.” 2019. Web. 27 Feb 2021.
Vancouver:
Restrepo Florez JM. Exploring metamaterials for the control of mass diffusion. [Internet] [Doctoral dissertation]. Georgia Tech; 2019. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1853/62685.
Council of Science Editors:
Restrepo Florez JM. Exploring metamaterials for the control of mass diffusion. [Doctoral Dissertation]. Georgia Tech; 2019. Available from: http://hdl.handle.net/1853/62685

Columbia University
21.
Bryant, Eric Cushman.
Capturing Evolving Size-Dependent Anisotropy from Brittle Fracture to Plasticity for Geological Materials.
Degree: 2020, Columbia University
URL: https://doi.org/10.7916/d8-xsrn-th19
► We present a computational framework for modeling geomaterials undergoing failure in the brittle and ductile regimes. This computational framework introduces anisotropic gradient regularization to replicate…
(more)
▼ We present a computational framework for modeling geomaterials undergoing failure in the brittle and ductile regimes. This computational framework introduces anisotropic gradient regularization to replicate a wide spectrum of size-dependent anisotropic constitutive responses exhibited in layered and sedimentary rock. Relevant subsurface applications include oil/gas wellbore completions, caprock evaluation for carbon sequestration in saline aquifers, and geothermal energy recovery. Considered failure modes are mixed-mode fracture, shear band formation due to plastic strain localization, and rate-dependent frictional slip along the propagated fracture's rock surface, subsequent to fracture closure.
Our nonlocal modeling framework extends the state-of-the-art gradient-enhanced plasticity and damage mechanics for frictional materials with a special treatment that injects bias for the regularization for different orientations. A novel contribution is that the formulations not only contains a regularization, but that the regularization also provides a method to introduce size-dependent anisotropies. Consequently, this treatment provides a new means to create non-associative flow via a variational framework while introducing different anisotropic responses for specimens of different sizes (introduced in Chapter 1). These anisotropic regularization modeling techniques are then applied to three classes of common geomechanics problems: critical state plasticity of clay and shale rock (Chapter 2), brittle fracture of rock (Chapter 3), and the plastic slip of interfaces and cracks (Chapter 4).
This combination, of established rock physics, local anisotropy, and size-dependent anisotropy enfranchised with diffusive regularization, is investigated. For instance, experimentation on uniaxially compressed specimens failing in the brittle regime reveals a repeatable typology of wing- and coalescent-crack patterns, broadly taken to indicate a mixed-mode fracture phenomenon particular to rock-like materials. In the ductile regime, biaxially compressed shale rock displays orientation-dependence of the plastic deformation difficult to capture merely by attributing anisotropy to the elastic response, with localization at or near the critical state. We numerically capture both these phenomena. Verification and/or validation is provided for proposed constitutive relations.
Subjects/Keywords: Rocks; Rocks – Fracture; Anisotropy; Geophysics
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Bryant, E. C. (2020). Capturing Evolving Size-Dependent Anisotropy from Brittle Fracture to Plasticity for Geological Materials. (Doctoral Dissertation). Columbia University. Retrieved from https://doi.org/10.7916/d8-xsrn-th19
Chicago Manual of Style (16th Edition):
Bryant, Eric Cushman. “Capturing Evolving Size-Dependent Anisotropy from Brittle Fracture to Plasticity for Geological Materials.” 2020. Doctoral Dissertation, Columbia University. Accessed February 27, 2021.
https://doi.org/10.7916/d8-xsrn-th19.
MLA Handbook (7th Edition):
Bryant, Eric Cushman. “Capturing Evolving Size-Dependent Anisotropy from Brittle Fracture to Plasticity for Geological Materials.” 2020. Web. 27 Feb 2021.
Vancouver:
Bryant EC. Capturing Evolving Size-Dependent Anisotropy from Brittle Fracture to Plasticity for Geological Materials. [Internet] [Doctoral dissertation]. Columbia University; 2020. [cited 2021 Feb 27].
Available from: https://doi.org/10.7916/d8-xsrn-th19.
Council of Science Editors:
Bryant EC. Capturing Evolving Size-Dependent Anisotropy from Brittle Fracture to Plasticity for Geological Materials. [Doctoral Dissertation]. Columbia University; 2020. Available from: https://doi.org/10.7916/d8-xsrn-th19

Texas A&M University
22.
Evans, Jordan Andrew.
Anisotropic Response of Laser Additively Manufactured Nuclear Alloys to Radiation Damage.
Degree: PhD, Materials Science and Engineering, 2017, Texas A&M University
URL: http://hdl.handle.net/1969.1/169649
► The impact of radiation-induced effects on the properties of alloys fabricated using additive manufacturing (AM) was evaluated through the implementation of ion beam irradiation testing…
(more)
▼ The impact of radiation-induced effects on the properties of alloys fabricated using additive manufacturing (AM) was evaluated through the implementation of ion beam irradiation testing followed by electron backscatter diffraction (EBSD), scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), nanoindentation, scanning probe microscopy (SPM), and transmission electron microscopy (TEM). Inconel 600 (I600) and 316L stainless steel (316L) rods were fabricated by Quad City Manufacturing Laboratory in collaboration with Lockheed Martin for this study. The rods were produced in three distinct orientations (vertical, horizontal, and 45°) using laser additive manufacturing (LAM). Conventionally manufactured I600 and 316L rods were purchased from Metal Samples, Inc. to enable comparative studies. The I600 and 316L LAM specimens were heat treated to 900 °C and 650 °C in argon with no cold working, respectively. Similarly, the conventionally manufactured I600 and 316L control specimens were cold rolled and annealed at 980 °C and 1040 °C in argon with no cold working, respectively.
XRD of unirradiated specimens showed differences in peak ratios between build orientations, indicating anisotropic grain structures for samples fabricated by LAM. All LAM rods contained significantly fewer coincidence site lattice (CSL) boundaries and more residual strain compared to the controls before and after irradiation, regardless of build direction, as determined by EBSD. Material performance parameters such as resistance to radiation-enhanced embrittlement, corrosion, creep, intergranular stress corrosion cracking, and hydrogen-induced cracking were inferred from CSL theory, which suggests that all LAM rods are more susceptible to grain boundary-related failure mechanisms than their conventionally manufactured counterparts. All alloys built by LAM are strongly textured with parallel to the build direction before and after irradiation. Directionally dependent Taylor Factor distributions suggest that resistance to slip depends on build direction where, from highest to lowest resistance: horizontal > 45° > vertical.
All I600 samples experienced radiation-induced segregation which, according to SEM/EDS and SPM studies, resulted in the formation of chromium carbide precipitates on to the irradiated surfaces. Strong anisotropic mechanical behavior was observed in the LAM rods, as measured by nanoindentation and bulk tensile testing. The hardness of the unirradiated as-annealed specimens, from greatest to least, is: horizontal > 45° > vertical. The radiation-induced hardening of LAM specimens, from greatest to least, is: horizontal > 45° > vertical. The orientation dependence of radiation-induced segregation and hardening mechanisms is discussed.
The ultimate outcome of this work is a first-of-a-kind high-dose radiation damage study of alloys fabricated by LAM, revealing that the radiation-induced changes in material properties for these alloys is dependent upon build orientation.
Advisors/Committee Members: McDeavitt, Sean (advisor), Perez-Nunez, Delia (committee member), Shao, Lin (committee member), Shamberger, Patrick (committee member), Tsvetkov, Pavel (committee member).
Subjects/Keywords: additive manufacturing; radiation damage; anisotropy
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Evans, J. A. (2017). Anisotropic Response of Laser Additively Manufactured Nuclear Alloys to Radiation Damage. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/169649
Chicago Manual of Style (16th Edition):
Evans, Jordan Andrew. “Anisotropic Response of Laser Additively Manufactured Nuclear Alloys to Radiation Damage.” 2017. Doctoral Dissertation, Texas A&M University. Accessed February 27, 2021.
http://hdl.handle.net/1969.1/169649.
MLA Handbook (7th Edition):
Evans, Jordan Andrew. “Anisotropic Response of Laser Additively Manufactured Nuclear Alloys to Radiation Damage.” 2017. Web. 27 Feb 2021.
Vancouver:
Evans JA. Anisotropic Response of Laser Additively Manufactured Nuclear Alloys to Radiation Damage. [Internet] [Doctoral dissertation]. Texas A&M University; 2017. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1969.1/169649.
Council of Science Editors:
Evans JA. Anisotropic Response of Laser Additively Manufactured Nuclear Alloys to Radiation Damage. [Doctoral Dissertation]. Texas A&M University; 2017. Available from: http://hdl.handle.net/1969.1/169649

Texas A&M University
23.
Gao, Kai.
Multiscale Method for Elastic Wave Propagation in the Heterogeneous, Anisotropic Media.
Degree: PhD, Geophysics, 2014, Texas A&M University
URL: http://hdl.handle.net/1969.1/153630
► Seismic wave simulation in realistic Earth media with full wavefield methods is a fundamental task in geophysical studies. Conventional approaches such as the finite-difference method…
(more)
▼ Seismic wave simulation in realistic Earth media with full wavefield methods is a fundamental task in geophysical studies. Conventional approaches such as the finite-difference method and the finite-element method solve the wave equation in geological models represented with discrete grids and elements. When the Earth model includes complex heterogeneities at multiple spatial scales, the simulation requires fine discretization and therefore a system with many degrees of freedom, which often exceeds current computational abilities. In this dissertation, I address this problem by proposing new multiscale methods for simulating elastic wave propagation based on previously developed algorithms for solving the elliptic partial differential equations and the acoustic wave equation. The fundamental motivation for developing the multiscale method is that it can solve the wave equation on a coarsely discretized mesh by incorporating the effects of fine-scale medium properties using so-called multiscale basis functions. This can greatly reduce computation time and degrees of freedom compared with conventional methods. I first derive a numerical homogenization method for arbitrarily heterogeneous, anisotropic media that utilizes the multiscale basis functions determined from a local linear elasticity equation to compute effective, anisotropic properties, and these equivalent elastic medium parameters can be used directly in existing elastic modeling algorithms. Then I extend the approach by constructing multiple basis functions using two types of appropriately defined local spectral linear elasticity problems. Given the eigenfunctions determined from local spectral problems, I develop a generalized multiscale finite-element method (GMsFEM) for elastic wave propagation in heterogeneous, anisotropic media in both continuous Galerkin (CG) and discontinuous Galerkin (DG) formulations. The advantage of the multiscale basis functions is they are model-dependent, unlike the predefined polynomial basis functions applied in conventional finite-element methods. For this reason, the GMsFEM can effectively capture the influence of fine-scale variation of the media. I present results for several numerical experiments to verify the effectiveness of both the numerical homogenization method and GMsFEM. These tests show that the effectiveness of the multiscale method relies on the appropriate choice of boundary conditions that are applied for the local problem in numerical homogenization method and on the selection of basis functions from a large set of eigenfunctions contained in local spectral problems in GMsFEM. I develop methods for solving both these problems, and the results confirm that the multiscale method can be powerful tool for providing accurate full wavefield solutions in heterogeneous, anisotropic media, yet with reduced computation time and degrees of freedom compared with conventional full wavefield modeling methods. Specially, I applied the DG-GMsFEM to the Marmousi-2 elastic model, and find that DG-GMsFEM can greatly reduce…
Advisors/Committee Members: Gibson Jr., Richard L (advisor), Efendiev, Yalchin (advisor), Chester, Frederick M (committee member), Everett, Mark E (committee member), Duan, Benchun (committee member).
Subjects/Keywords: elastic wave; anisotropy; multiscale
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gao, K. (2014). Multiscale Method for Elastic Wave Propagation in the Heterogeneous, Anisotropic Media. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/153630
Chicago Manual of Style (16th Edition):
Gao, Kai. “Multiscale Method for Elastic Wave Propagation in the Heterogeneous, Anisotropic Media.” 2014. Doctoral Dissertation, Texas A&M University. Accessed February 27, 2021.
http://hdl.handle.net/1969.1/153630.
MLA Handbook (7th Edition):
Gao, Kai. “Multiscale Method for Elastic Wave Propagation in the Heterogeneous, Anisotropic Media.” 2014. Web. 27 Feb 2021.
Vancouver:
Gao K. Multiscale Method for Elastic Wave Propagation in the Heterogeneous, Anisotropic Media. [Internet] [Doctoral dissertation]. Texas A&M University; 2014. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1969.1/153630.
Council of Science Editors:
Gao K. Multiscale Method for Elastic Wave Propagation in the Heterogeneous, Anisotropic Media. [Doctoral Dissertation]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/153630

Penn State University
24.
Desser, Elizabeth M.
Anisotropy beneath the Tibetan Plateau: A survey of shear wave splitting analyses
.
Degree: 2011, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/12604
► One of the most impressive surficial features on Earth is the Himalayan-Tibetan orogen, comprising the Himalaya Range and the associated Tibetan plateau to its northeast.…
(more)
▼ One of the most impressive surficial features on Earth is the Himalayan-Tibetan orogen, comprising the Himalaya Range and the associated Tibetan plateau to its northeast. Diverse experiments have been conducted in Tibet in attempts to advance our understanding of the state of
anisotropy in the upper mantle beneath the plateau. Results from previous studies of shear wave splitting on the Tibetan Plateau suggest several models of mantle lithospheric flow, such as the rotational flow patterns observed around the Eastern Himalaya syntaxis. I use the SplitLab processing environment to measure the shear wave splitting of teleseismic shear wave SKS and SKKS phases recorded on 386 broadband seismic stations within nine networks deployed across the Tibetan Plateau. I observe some strong variations in SKS splitting parameters across major terrane boundaries but also detect strong lateral variations in the SKS splitting in the west-to-east direction within both the Lhasa and Qiangtang terranes. In the Lhasa terrane, the apparent splitting decreases from west to east, in contrast with the Qiangtang terrane, which shows an eastward increase in SKS splitting. Patterns in much of the Himalaya and in southeastern Tibet are complex with rapid apparent changes in the overall SKS splitting parameters.
Advisors/Committee Members: Charles James Ammon, Thesis Advisor/Co-Advisor, Charles James Ammon, Thesis Advisor/Co-Advisor.
Subjects/Keywords: Tibet; anisotropy; shear wave splitting
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Desser, E. M. (2011). Anisotropy beneath the Tibetan Plateau: A survey of shear wave splitting analyses
. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/12604
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Desser, Elizabeth M. “Anisotropy beneath the Tibetan Plateau: A survey of shear wave splitting analyses
.” 2011. Thesis, Penn State University. Accessed February 27, 2021.
https://submit-etda.libraries.psu.edu/catalog/12604.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Desser, Elizabeth M. “Anisotropy beneath the Tibetan Plateau: A survey of shear wave splitting analyses
.” 2011. Web. 27 Feb 2021.
Vancouver:
Desser EM. Anisotropy beneath the Tibetan Plateau: A survey of shear wave splitting analyses
. [Internet] [Thesis]. Penn State University; 2011. [cited 2021 Feb 27].
Available from: https://submit-etda.libraries.psu.edu/catalog/12604.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Desser EM. Anisotropy beneath the Tibetan Plateau: A survey of shear wave splitting analyses
. [Thesis]. Penn State University; 2011. Available from: https://submit-etda.libraries.psu.edu/catalog/12604
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University
25.
Kotb, Abdelrahman Mostafa.
Pore Network Connectivity and Its Impacts on Electrical Resistivity of Anisotropic Rocks with Complex Pore Structure.
Degree: MS, Petroleum Engineering, 2015, Texas A&M University
URL: http://hdl.handle.net/1969.1/156294
► Core data and well-log interpretation results are usually comparable in homogenous conventional reservoirs. However, in the case of thinly-bedded, heterogeneous formations consisting of organic-rich mudrocks…
(more)
▼ Core data and well-log interpretation results are usually comparable in homogenous conventional reservoirs. However, in the case of thinly-bedded, heterogeneous formations consisting of organic-rich mudrocks and carbonates, core-log calibration and integration are challenging. The calibration of well-log interpretation results with core data is hence justified for thick homogeneous beds. Consequently, petrophysical properties (e.g., fluid saturation) estimated from well logs are not generally in agreement with core measurements. Therefore, upscaling of petrophysical properties from core-scale to log-scale is essential to reconcile measurements obtained from different scales. Although petrophysical measurements vary from core-scale to log-scale, previous publications have shown that the relationship between formation factor and porosity is consistent over a wide-scale range in homogenous sandstones. These correlations, however, do not persist in rocks with complex pore structure and rock fabric (e.g., carbonates).
This research investigated the persistence of a correlation between the electrical resistivity and the directional connectivity tensor at different scales within the micron scale in sandstone and carbonate examples. To fulfill this objective, three-dimensional (3D), pore-scale rock images were obtained from micro-CT (Computed Tomography) images. Then, each 3D pore-scale image was divided into subsamples of varying sizes. Afterwards, tortuosity of the networks of the electrically conductive rock components (e.g., formation water) was estimated in each subsample. The next step was to numerically solve the Laplace’s equation to estimate electric field distribution and effective electrical resistivity of each subsample. The last step involved calculating the directional connectivity tensor based on the estimated tortuosity and volumetric concentration of each conductive component in the samples and subsamples. Finally, the impact of directional connectivity of pore network on electrical resistivity was quantified.
The results confirmed the existence of a correlation between directional connectivity and electrical resistivity at different micron scales in the samples studied in this thesis. Improvements of up to 59% and 54% were observed in the proposed relationship compared to the conventional relationship between porosity and electrical resistivity in fully and partially water-saturated samples, respectively. An improvement of up to 50% in estimates of water saturation was observed when the directional connectivity of pore network was taken into account.
Advisors/Committee Members: Heidari, Zoya (advisor), Ayers, Walter (committee member), Sun, Yuefeng (committee member).
Subjects/Keywords: Heterogeneous; Anisotropy; Directional connectivity
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kotb, A. M. (2015). Pore Network Connectivity and Its Impacts on Electrical Resistivity of Anisotropic Rocks with Complex Pore Structure. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/156294
Chicago Manual of Style (16th Edition):
Kotb, Abdelrahman Mostafa. “Pore Network Connectivity and Its Impacts on Electrical Resistivity of Anisotropic Rocks with Complex Pore Structure.” 2015. Masters Thesis, Texas A&M University. Accessed February 27, 2021.
http://hdl.handle.net/1969.1/156294.
MLA Handbook (7th Edition):
Kotb, Abdelrahman Mostafa. “Pore Network Connectivity and Its Impacts on Electrical Resistivity of Anisotropic Rocks with Complex Pore Structure.” 2015. Web. 27 Feb 2021.
Vancouver:
Kotb AM. Pore Network Connectivity and Its Impacts on Electrical Resistivity of Anisotropic Rocks with Complex Pore Structure. [Internet] [Masters thesis]. Texas A&M University; 2015. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1969.1/156294.
Council of Science Editors:
Kotb AM. Pore Network Connectivity and Its Impacts on Electrical Resistivity of Anisotropic Rocks with Complex Pore Structure. [Masters Thesis]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/156294

Texas A&M University
26.
Huang, Yibin.
Stream Depletion and Pumping Test Interpretation in a Horizontally Anisotropic Aquifer Near a Stream.
Degree: MS, Water Management and Hydrological Science, 2016, Texas A&M University
URL: http://hdl.handle.net/1969.1/174642
► Conventional pumping test theories such as Theis solution often assume a horizontally isotropic media. Horizontal anisotropy exists in certain aquifer settings and its impact on…
(more)
▼ Conventional pumping test theories such as Theis solution often assume a horizontally isotropic media. Horizontal
anisotropy exists in certain aquifer settings and its impact on pumping tests is not clearly demonstrated before, particularly when the aquifer is bounded by a stream. In this thesis, based on a newly developed mathematical model for pumping tests in a horizontally anisotropic aquifer bounded by a stream, the corresponding interpretation procedures will be illustrated. Stream depletion will be calculated as a result of stream bank pumping based on the new model as well. The results of this research reflect that (1) aquifer parameters derived from newly developed interpretation methods are acceptable in the range of allowable error; so these methods can be used in practical field experiment; (2) with the increase of Ta/Tb, stream depletion rate under the steady state also increases where Ta and Ta are the major and minor principal transmissivity values ( Ta>Tb); (3) when the angle between the X axis and the direction of Ta increases from 0 to pi/2, stream depletion increases, where the X-axis is one of the working coordinate; conversely, when such an angle increases from pi/2 to pi, stream depletion decreases. This research is expected to fill the gap of knowledge on present stream-aquifer interaction and pumping test theories for aquifers.
Advisors/Committee Members: Zhan, Hongbin (advisor), Knappett, Peter (committee member), Sparks, David (committee member).
Subjects/Keywords: Stream depletion; Anisotropy; Pumping test
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APA (6th Edition):
Huang, Y. (2016). Stream Depletion and Pumping Test Interpretation in a Horizontally Anisotropic Aquifer Near a Stream. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174642
Chicago Manual of Style (16th Edition):
Huang, Yibin. “Stream Depletion and Pumping Test Interpretation in a Horizontally Anisotropic Aquifer Near a Stream.” 2016. Masters Thesis, Texas A&M University. Accessed February 27, 2021.
http://hdl.handle.net/1969.1/174642.
MLA Handbook (7th Edition):
Huang, Yibin. “Stream Depletion and Pumping Test Interpretation in a Horizontally Anisotropic Aquifer Near a Stream.” 2016. Web. 27 Feb 2021.
Vancouver:
Huang Y. Stream Depletion and Pumping Test Interpretation in a Horizontally Anisotropic Aquifer Near a Stream. [Internet] [Masters thesis]. Texas A&M University; 2016. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1969.1/174642.
Council of Science Editors:
Huang Y. Stream Depletion and Pumping Test Interpretation in a Horizontally Anisotropic Aquifer Near a Stream. [Masters Thesis]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/174642

Leiden University
27.
Fermin, Remko.
In-plane resistivity anisotropy of single crystal SmFeAsO.
Degree: 2018, Leiden University
URL: http://hdl.handle.net/1887/61180
► In the vicinity of the superconducting dome in the phase diagram of iron-pnictides there exist a magnetically ordered phase accompanied by a nematic phase and…
(more)
▼ In the vicinity of the superconducting dome in the phase diagram of
iron-pnictides there exist a magnetically ordered phase accompanied by a
nematic phase and a structural transition. Since all three phases belong to the
same point group symmetry, it is a priori difficult to establish which of these
phases is dominant. The fluctuations associated with the energetically
dominant transition have been proposed as the driving force behind
electronic pairing in the superconducting state. Therefore the identification
of this transition is essential for further understanding the physics behind
superconductivity in iron-pnictides. This thesis explores the relation
between nematic strength and the superconducting critical temperatures in
the pnictides. The in-plane resistivity
anisotropy of single crystal SmFeAsO
(Tc =55 K in optimally F-doped SmFeAs[O,F]) was investigated using four
different sample geometries structured by focused ion beam methods. The
results are compared to other iron-pnictides and it was observed that the
maximal resistivity
anisotropy is similar as to that in other iron-pnictides.
These initial results clearly lay the groundwork for future experimental
studies, in particular probing the relation between the crystal lattice and the
nematicity.
Advisors/Committee Members: Oosterkamp, T.H (advisor).
Subjects/Keywords: SmFeAsO; Resistivity Anisotropy; FIB
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APA ·
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MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Fermin, R. (2018). In-plane resistivity anisotropy of single crystal SmFeAsO. (Masters Thesis). Leiden University. Retrieved from http://hdl.handle.net/1887/61180
Chicago Manual of Style (16th Edition):
Fermin, Remko. “In-plane resistivity anisotropy of single crystal SmFeAsO.” 2018. Masters Thesis, Leiden University. Accessed February 27, 2021.
http://hdl.handle.net/1887/61180.
MLA Handbook (7th Edition):
Fermin, Remko. “In-plane resistivity anisotropy of single crystal SmFeAsO.” 2018. Web. 27 Feb 2021.
Vancouver:
Fermin R. In-plane resistivity anisotropy of single crystal SmFeAsO. [Internet] [Masters thesis]. Leiden University; 2018. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1887/61180.
Council of Science Editors:
Fermin R. In-plane resistivity anisotropy of single crystal SmFeAsO. [Masters Thesis]. Leiden University; 2018. Available from: http://hdl.handle.net/1887/61180

West Virginia University
28.
Nasr, Charbel.
Study of stress anisotropy on shale rock permeability.
Degree: MS, Petroleum and Natural Gas Engineering, 2017, West Virginia University
URL: https://doi.org/10.33915/etd.4011
;
https://researchrepository.wvu.edu/etd/4011
► Permeability is one of the most time-consuming rock petro-physical properties to measure, especially in the case of shales and tight rocks with Micro-Darcy ranges.…
(more)
▼ Permeability is one of the most time-consuming rock petro-physical properties to measure, especially in the case of shales and tight rocks with Micro-Darcy ranges. Several unsteady state methods like GRI, Pressure Pulse Decay (PPD) have been applied to measure permeability but unfortunately results are not accurate due to the limitations to in situ stress conditions, repeatability and reproducibility issues. To overcome this limitations a system under steady state condition and with equal confining and axial pressure has been developed, obtaining remarkable permeability measurements. This system was designed and assembled by Zamirian et al 2015 referred to as Precision Petrophysical Analysis Laboratory (PPAL). Shale reservoirs are heterogeneous, anisotropic and are
subject to in-situ stress state. In-situ stresses are divided into overburden pressures (δ_v), maximum (δ_H) and minimum horizontal stresses (δ_h) which are usually different in magnitude. Stress dependent permeability plays an important role since it contributes to the gas transport throughout the matrix, natural fractures and hydraulic fractures. A test has been done using the PPAL system, but still has stress limitations since the axial and confining stress applied to the core sample are equal, unlike the in situ stress conditions. Because of that, this research introduces the methodology of using a Tri-axial core holder in the PPAL system (T-PPAL) in order to understand how stress
anisotropy affects permeability. Two cases will be studied, using T-PPAL, the first case is to measure vertical permeability (K_v), (when the core plug is vertically drilled) under in situ-stress state, where axial stress (δ_v) is larger than confining stress (δ_h). The second case is to measure horizontal permeability (K_h), (when the core plug is horizontally drilled) at different horizontal stress anisotropies defined as the ratio of maximum over minimum horizontal stress (δ_H/δ_h). The tri-axial test designed for PPAL will provide a better understanding of how stress
anisotropy affects shale rock permeability.
Advisors/Committee Members: Sam Ameri, Ming Gu, Kashy Aminian.
Subjects/Keywords: Anisotropy; In situ stress state
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Nasr, C. (2017). Study of stress anisotropy on shale rock permeability. (Thesis). West Virginia University. Retrieved from https://doi.org/10.33915/etd.4011 ; https://researchrepository.wvu.edu/etd/4011
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Nasr, Charbel. “Study of stress anisotropy on shale rock permeability.” 2017. Thesis, West Virginia University. Accessed February 27, 2021.
https://doi.org/10.33915/etd.4011 ; https://researchrepository.wvu.edu/etd/4011.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Nasr, Charbel. “Study of stress anisotropy on shale rock permeability.” 2017. Web. 27 Feb 2021.
Vancouver:
Nasr C. Study of stress anisotropy on shale rock permeability. [Internet] [Thesis]. West Virginia University; 2017. [cited 2021 Feb 27].
Available from: https://doi.org/10.33915/etd.4011 ; https://researchrepository.wvu.edu/etd/4011.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Nasr C. Study of stress anisotropy on shale rock permeability. [Thesis]. West Virginia University; 2017. Available from: https://doi.org/10.33915/etd.4011 ; https://researchrepository.wvu.edu/etd/4011
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Houston
29.
Gan, Yuandi 1990-.
EFFECT OF MATERIAL CONTRAST ON ANISOTROPY AND DISPERSION OF LAYERED PERIODIC MEDIUM.
Degree: MS, Geophysics, 2014, University of Houston
URL: http://hdl.handle.net/10657/1637
► In order to research the anisotropy and dispersion features of media with aligned fractures, models which approximately describe the media are constructed. For the case…
(more)
▼ In order to research the
anisotropy and dispersion features of media with aligned fractures, models which approximately describe the media are constructed. For the case in which crack density is very high and aspect ratio may be very low, the cracked medium can be described as a layered periodic medium, in which the aligned fractures in question are described as layers.
Given a layered periodic medium consisting of all solid layers, the effect of the contrast between individual layers on the behavior of
anisotropy is examined. The effect of shear modulus contrast on
anisotropy is essential. If shear moduli of two layers are equal, the effective medium is isotropic. The increase of bulk modulus contrast shifts the maximum SV -wave velocity point to that of smaller angle.
For the layered periodic medium consisting of alternating solid and fluid layers, the effects on both
anisotropy and frequency dispersion are then examined. There will be dispersion for propagating P-wave, and thereby stop-bands exist. For the wave propagates perpendicular to the layering, the stop-bands as a function of phys- ical properties of individual layers are studied. When wavelength is much greater than the spatial period of the medium, there are two modes of P-wave, the fast and slow P-wave.
For cases in which crack density is low and aspect ratio is relatively high, the
anisotropy is characterized using the Eshelby-Cheng method. The increase of bulk modulus contrast will increase the
anisotropy of the effective medium. As the aspect ratio increases from 0.1 to 0.5, the
anisotropy of P-wave and SV -wave increases.
Advisors/Committee Members: Chesnokov, Evgeni M. (advisor), Li, Aibing (committee member), Kouri, Donald J. (committee member).
Subjects/Keywords: Layered periodic media; Anisotropy; Dispersion
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gan, Y. 1. (2014). EFFECT OF MATERIAL CONTRAST ON ANISOTROPY AND DISPERSION OF LAYERED PERIODIC MEDIUM. (Masters Thesis). University of Houston. Retrieved from http://hdl.handle.net/10657/1637
Chicago Manual of Style (16th Edition):
Gan, Yuandi 1990-. “EFFECT OF MATERIAL CONTRAST ON ANISOTROPY AND DISPERSION OF LAYERED PERIODIC MEDIUM.” 2014. Masters Thesis, University of Houston. Accessed February 27, 2021.
http://hdl.handle.net/10657/1637.
MLA Handbook (7th Edition):
Gan, Yuandi 1990-. “EFFECT OF MATERIAL CONTRAST ON ANISOTROPY AND DISPERSION OF LAYERED PERIODIC MEDIUM.” 2014. Web. 27 Feb 2021.
Vancouver:
Gan Y1. EFFECT OF MATERIAL CONTRAST ON ANISOTROPY AND DISPERSION OF LAYERED PERIODIC MEDIUM. [Internet] [Masters thesis]. University of Houston; 2014. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10657/1637.
Council of Science Editors:
Gan Y1. EFFECT OF MATERIAL CONTRAST ON ANISOTROPY AND DISPERSION OF LAYERED PERIODIC MEDIUM. [Masters Thesis]. University of Houston; 2014. Available from: http://hdl.handle.net/10657/1637

University of Houston
30.
Sosa, Armando 1981-.
ASSESSMENT OF AZIMUTHAL VARIATIONS IN DEPTH MIGRATED MARINE WIDE-AZIMUTH DATA: WORKFLOW DERIVATION AND EXAMPLES FROM THE EAST BREAKS REGION OF THE GULF OF MEXICO.
Degree: MS, Geophysics, 2012, University of Houston
URL: http://hdl.handle.net/10657/597
► Current seismic acquisition geometries are designed to record a broader range of azimuths. While illumination of subsalt structures is a major factor when planning these…
(more)
▼ Current seismic acquisition geometries are designed to record a broader range of azimuths. While illumination of subsalt structures is a major factor when planning these surveys, azimuthal variations due to heterogeneity and
anisotropy can also significantly impact the imaging of these targets if they are not well understood. This study presents a practical workflow for detecting and assessing the significance of azimuthal variations on wide-azimuth data, in an effort to start to better utilize the azimuthal aspect of this type of survey. The assessment itself was performed in depth migrated images of wide-azimuth data from the East Breaks region of the Gulf of Mexico, which were decomposed into azimuth-sectored angle-domain gathers post-imaging. This data domain provided great flexibility to the analysis of azimuthal moveout anomalies, as different subsets of common angle volumes were evaluated depending on their level of contributions to the imaging of a given geologic target. As the derived workflow was tested in different scenarios, it became clear that analyzing a variety of attributes, volumetrically or at specific interpreted horizons, delivered qualitative results that confirmed the presence of azimuthal variations and how irregular or chaotic these were, depending on the area of interest. Throughout this study, it was quite important to develop quality control plots that aid the validation of the propose techniques. Particularly significant were the cross-correlation azimuthal residual maps and the attributes used to rule out whether an azimuthal anomaly was being induced by the migration models, since improving the fitting of the data by using a higher order of symmetry system was outside of the scope for this study. It was also concluded that while the resolution of the dataset used in this study was typical for depth migration images in the region, it was not ideal in terms of frequency and azimuthal sampling. However, this analysis did provide multiple insights into the intricacies of assessing azimuthal variations in image space.
Advisors/Committee Members: Zhou, Hua-Wei (advisor), Whitmore, N. Daniel (committee member), Chesnokov, Evgeni M. (committee member), Thomsen, Leon (committee member).
Subjects/Keywords: Seismic; Anisotropy; Wide-Azimuth; Geophysics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sosa, A. 1. (2012). ASSESSMENT OF AZIMUTHAL VARIATIONS IN DEPTH MIGRATED MARINE WIDE-AZIMUTH DATA: WORKFLOW DERIVATION AND EXAMPLES FROM THE EAST BREAKS REGION OF THE GULF OF MEXICO. (Masters Thesis). University of Houston. Retrieved from http://hdl.handle.net/10657/597
Chicago Manual of Style (16th Edition):
Sosa, Armando 1981-. “ASSESSMENT OF AZIMUTHAL VARIATIONS IN DEPTH MIGRATED MARINE WIDE-AZIMUTH DATA: WORKFLOW DERIVATION AND EXAMPLES FROM THE EAST BREAKS REGION OF THE GULF OF MEXICO.” 2012. Masters Thesis, University of Houston. Accessed February 27, 2021.
http://hdl.handle.net/10657/597.
MLA Handbook (7th Edition):
Sosa, Armando 1981-. “ASSESSMENT OF AZIMUTHAL VARIATIONS IN DEPTH MIGRATED MARINE WIDE-AZIMUTH DATA: WORKFLOW DERIVATION AND EXAMPLES FROM THE EAST BREAKS REGION OF THE GULF OF MEXICO.” 2012. Web. 27 Feb 2021.
Vancouver:
Sosa A1. ASSESSMENT OF AZIMUTHAL VARIATIONS IN DEPTH MIGRATED MARINE WIDE-AZIMUTH DATA: WORKFLOW DERIVATION AND EXAMPLES FROM THE EAST BREAKS REGION OF THE GULF OF MEXICO. [Internet] [Masters thesis]. University of Houston; 2012. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10657/597.
Council of Science Editors:
Sosa A1. ASSESSMENT OF AZIMUTHAL VARIATIONS IN DEPTH MIGRATED MARINE WIDE-AZIMUTH DATA: WORKFLOW DERIVATION AND EXAMPLES FROM THE EAST BREAKS REGION OF THE GULF OF MEXICO. [Masters Thesis]. University of Houston; 2012. Available from: http://hdl.handle.net/10657/597
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