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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Parsimonious migration 3-C 3-D VSP migration /

Agnihotri, Yogesh, January 2006 (has links)
Thesis (M.S.) -- University of Texas at Dallas, 2006 / Includes vita. Includes bibliographical references (leaves 24-25)
2

Seismic constraints on structure beneath hotspots : earthquake tomography & finite frequency tomography approaches /

Yang, Ting. January 2006 (has links)
Thesis (Ph. D.)--University of Rhode Island, 2006. / Typescript. Includes bibliographical references (leaves 131-150).
3

Common conversion point stacking for P-SV converted waves /

Zhang, Yaohui. January 1992 (has links)
Thesis (Ph.D.)--University of Tulsa, 1992. / Bibliography: leaves 123-131.
4

Teleseismic array analysis of upper mantle compressional velocity structure

Walck, Marianne C. January 1984 (has links)
Thesis (Ph. D.)--California Institute of Technology, 1984. / Includes bibliographical references (leaves 213-230).
5

Investigation of Pn wave propagation in Oregon

Ganoe, Steven J. 20 October 1982 (has links)
Graduation date: 1983 / Best scan available for figures.
6

Post- and pre-stack attribute analysis and inversion of Blackfoot 3Dseismic dataset

Swisi, Abdulsalam Amer 19 October 2009
The objective of this research is comparative analysis of several standard and one new seismic post- and pre-stack inversion methods and Amplitude Variation with Offset (AVO) attribute analysis in application to the CREWES Blackfoot 3D dataset. To prepare the data to the inversion, I start with processing the dataset by using ProMAX software. This processing, in general, includes static and refraction corrections, velocity analysis and stacking the data. The results show good quality images, which are suitable for inversion.<p> Five types of inversion methods are applied to the dataset and compared. Three of these methods produce solutions for the post-stack Acoustic Impedance (AI) and are per-formed by using the industry-standard Hampson-Russell software. The fourth method uses our in-house algorithm called SILC and implemented in IGeoS seismic processing system. In the fifth approach, the pre-stack gathers are inverted for elastic impedance by range-limited stacking of the common-midpoint (CMP) gathers in offsets and/or angles and then performing independent inversion of angle stack. Further, simultaneous inversion is applied to pre-stack seismic data to invert for both the P- and S-wave impedances. These im-pedances are used to extract the Lamé parameters multiplied by density (LMR), and used to extract the ratios between the P- and S-wave velocities. In addition, CMP gathers are used to produce AVO attribute images, which are good indicators of gas reservoirs. Fi-nally, the results of the different inversion techniques are interpreted and correlated with well-log data and used to characterize the reservoir.<p> The different inversion results show clearly the reservoir with its related low im-pedance within the channel. The post-stack inversion gives the best results; in particular, the model-based inversion shows smoothed images of it while SILC provides a different, higher-resolution image. The elastic impedance also gives results similar to the post-stack inversion. Pre-stack inversion and AVO attributes give reasonable results in cross sections near the center of study area. In other areas, performance of pre-stack inversion is poorer, apparently because of reflection aperture limitations.
7

Post- and pre-stack attribute analysis and inversion of Blackfoot 3Dseismic dataset

Swisi, Abdulsalam Amer 19 October 2009 (has links)
The objective of this research is comparative analysis of several standard and one new seismic post- and pre-stack inversion methods and Amplitude Variation with Offset (AVO) attribute analysis in application to the CREWES Blackfoot 3D dataset. To prepare the data to the inversion, I start with processing the dataset by using ProMAX software. This processing, in general, includes static and refraction corrections, velocity analysis and stacking the data. The results show good quality images, which are suitable for inversion.<p> Five types of inversion methods are applied to the dataset and compared. Three of these methods produce solutions for the post-stack Acoustic Impedance (AI) and are per-formed by using the industry-standard Hampson-Russell software. The fourth method uses our in-house algorithm called SILC and implemented in IGeoS seismic processing system. In the fifth approach, the pre-stack gathers are inverted for elastic impedance by range-limited stacking of the common-midpoint (CMP) gathers in offsets and/or angles and then performing independent inversion of angle stack. Further, simultaneous inversion is applied to pre-stack seismic data to invert for both the P- and S-wave impedances. These im-pedances are used to extract the Lamé parameters multiplied by density (LMR), and used to extract the ratios between the P- and S-wave velocities. In addition, CMP gathers are used to produce AVO attribute images, which are good indicators of gas reservoirs. Fi-nally, the results of the different inversion techniques are interpreted and correlated with well-log data and used to characterize the reservoir.<p> The different inversion results show clearly the reservoir with its related low im-pedance within the channel. The post-stack inversion gives the best results; in particular, the model-based inversion shows smoothed images of it while SILC provides a different, higher-resolution image. The elastic impedance also gives results similar to the post-stack inversion. Pre-stack inversion and AVO attributes give reasonable results in cross sections near the center of study area. In other areas, performance of pre-stack inversion is poorer, apparently because of reflection aperture limitations.
8

Improved sweep efficiency through seismic wave stimulation

Allahverdiyev, Parviz Qadir 06 November 2012 (has links)
Enhanced oil recovery as a result of earthquake events has been repeatedly observed and reported. The main advantage of a seismic wave-based EOR is that it is not costly and is easy to deploy. However, the method has not yet been fully investigated; the production enhancement mechanisms need to be identified and confirmed. This thesis shows a possible production mechanism and preliminary estimate of incremental oil recovery due to seismic wave stimulation. The production mechanism is improved sweep efficiency through viscous cross-flow between different permeability layers of a reservoir as a result of fluid pressure oscillations. In this thesis, we studied a possible viscous cross-flow generation between a fracture and a rock matrix of a fractured reservoir model as a result of fluid pressure oscillations. We considered time-harmonic water flooding as a way of sending seismic waves to the reservoir model. To calculate a cross-flow pressure gradient, we investigated oscillatory pressure propagation equations within the rock matrix and the fracture of the reservoir model. According to our results, the volume of the mobilized oil because of the time-harmonic water flooding during one day of stimulation from the fractured reservoir model is in the order of several barrels. / text
9

A focal mechanism study using both P-wave first motions and S-wave polarization angles

Smith, Gordon Egbert 08 1900 (has links)
No description available.
10

A velocity-tracking filter for improved estimation of seismic signals

Letton, Winsor 08 1900 (has links)
No description available.

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