Show simple item record



Item Description

dc.contributor.author Hood, Julie A en_US
dc.date.accessioned 2009-07-15T17:49:46Z en_US
dc.date.available 2009-07-15T17:49:46Z en_US
dc.date.issued 1990 en_US
dc.identifier.uri http://hdl.handle.net/10125/9834 en_US
dc.description Typescript. en_US
dc.description Thesis (Ph. D.)--University of Hawaii at Manoa, 1990. en_US
dc.description Includes bibliographical references (leaves 44-45) en_US
dc.description Microfiche. en_US
dc.description vii, 45 leaves, bound ill. 29 cm en_US
dc.description.abstract A heterogeneous mixture of isotropic elements may appear homogeneous and anisotropic when the scale of its fabric is smaller than the seismic wavelengths that measure it. This fabric can result from thin layering, aligned crystals, anisotropic background stress, aligned fractures, and/or oriented microcracks. Horizontal layering in sedimentary basins and the oceanic crust generates transverse isotropy, a hexagonal symmetry with a vertical symmetry axis, an extremely common form of anisotropy. The elastic properties of transversely isotropic media do not vary with azimuth. With the advent of multi-component seismometers and walk-around experiments, however, azimuthal variation is now frequently observed as well. This azimuthal anisotropy usually results from steeply dipping aligned fractures or microcracks. Realistic earth models must include all the significant constituent anisotropies of fracture systems and the backgrounds in which these fracture systems are embedded. The anisotropy increases in complexity as the number of different systems incorporated into the medium increases. Considering all possible combinations of constituents, a variety of anisotropies can result. For example, embedding a fracture system into an isotropic background can produce anisotropy with a symmetry as simple as hexagonal or as complex as triclinic. Analysis of either fractures or the background requires separating the two anisotropic effects otherwise they interfere. As long as there is at least one symmetry plane in fractured anisotropic media, the contribution of the fractures to the elastic modulus matrix of the background can be removed. The fracture properties can be evaluated by imposing the background symmetry constraints. Once the fracture compliances are obtained, the elastic properties of the unfractured background and the complexity of its symmetry can be determined. en_US
dc.language.iso en-US en_US
dc.relation Theses for the degree of Doctor of Philosophy (University of Hawaii at Manoa). Geology and Geophysics; no. 2468 en_US
dc.rights All UHM dissertations and theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission from the copyright owner. en_US
dc.subject Geology, Structural -- Mathematical models en_US
dc.subject Submarine geology -- Mathematical models en_US
dc.title Fracture estimation in anisotropic media en_US
dc.type Thesis en_US
dc.type.dcmi Text en_US

Item File(s)

Description Files Size Format View
Restricted for viewing only uhm_phd_9030563_r.pdf 1.237Mb PDF View/Open
For UH users only uhm_phd_9030563_uh.pdf 1.221Mb PDF View/Open

This item appears in the following Collection(s)

Show simple item record

Search


Advanced Search

Browse

My Account

Statistics

About