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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

Selected growth and interaction characteristics of seafloor faults in the central Mississippi Canyon Offshore Continental Shelf (OCS) area, northern Gulf of Mexico

Wegner, Scott Ashley 16 August 2006 (has links)
The characteristics of some shallow faults in the Gulf of Mexico interpreted to be active are poorly understood. A better understanding of these faults will increase our understanding of formerly and presently active geologic processes in the Gulf. Specifically, the characteristics of growth, interaction, and linkage of faults are of interest. Most of the Gulf has seen continuous clastic sediment deposition since the end of continental rifting in the middle Mesozoic. The Gulf is a tectonically quiescent basin, with the only major structural processes being salt diapirism and subsidence. Numerous styles of faulting have been observed in the Gulf, with each style being related to a specific type of deformation. Numerous authors have concluded that fault growth processes generally involve tipline propagation and linkage of faults. Evidence of these processes has been observed in seismic data sets. This investigation uses a HR 3-D seismic data set to characterize growth, interaction, and linkage of a fault set in the northern Gulf of Mexico. This work shows that linked and interacting faults are present in the study area. These conclusions were reached using measurements of throw on horizons offset by several faults and interpreting the throw data using a model of fault growth and interaction based on separate processes of growth by tipline propagation and growth by linkage of smaller faults. The ratio of these parameters for a fault population can be described by a power law relationship. For the fault set considered here, the power law was found to be valid.
2

Selected growth and interaction characteristics of seafloor faults in the central Mississippi Canyon Offshore Continental Shelf (OCS) area, northern Gulf of Mexico

Wegner, Scott Ashley 16 August 2006 (has links)
The characteristics of some shallow faults in the Gulf of Mexico interpreted to be active are poorly understood. A better understanding of these faults will increase our understanding of formerly and presently active geologic processes in the Gulf. Specifically, the characteristics of growth, interaction, and linkage of faults are of interest. Most of the Gulf has seen continuous clastic sediment deposition since the end of continental rifting in the middle Mesozoic. The Gulf is a tectonically quiescent basin, with the only major structural processes being salt diapirism and subsidence. Numerous styles of faulting have been observed in the Gulf, with each style being related to a specific type of deformation. Numerous authors have concluded that fault growth processes generally involve tipline propagation and linkage of faults. Evidence of these processes has been observed in seismic data sets. This investigation uses a HR 3-D seismic data set to characterize growth, interaction, and linkage of a fault set in the northern Gulf of Mexico. This work shows that linked and interacting faults are present in the study area. These conclusions were reached using measurements of throw on horizons offset by several faults and interpreting the throw data using a model of fault growth and interaction based on separate processes of growth by tipline propagation and growth by linkage of smaller faults. The ratio of these parameters for a fault population can be described by a power law relationship. For the fault set considered here, the power law was found to be valid.
3

A core-based assessment of the spatial relationship of small faults associated with a basement-controlled, large normal fault in the Hickory Sandstone

Graff, Mitchell C 30 October 2006 (has links)
This research characterized a system of small faults (displacement < 0.3 m) in seven closely-spaced continuous 2.4 inch (6.1 cm) diameter cores. Cores were obtained from central Texas, on the western edge of the Llano Uplift. Cores penetrate a dip-slip dominant, normal fault (Nobles Fault) with 18.3 m (60 ft) of stratigraphic throw. The spatial, geometric and kinematic attributes of small faults within the Nobles Fault system were characterized to explore potential cause-and-effect relationships. To quantify spatial distributions, a "density" measure based on individual small fault magnitude was utilized. Approximately half of the small faults in the core possessed no discernible offset markers; thus displacement amount for these faults could not be measured directly. Using a nonparametric method in which an alternating conditional expectation determined optimal transformations for the data, a statistically significant empirical correlation was established for faults with measurable gouge thickness, displacement, protolith mean grain size and sorting. Gouge thickness of small faults was found to be dependant upon the displacement amount of the small fault and the textural characteristics of the host protolith. The role of protolith lithology, proximity to crystalline basement, and structural position relative to the Nobles Fault system were examined to explain observed ubiquitous spatial distribution of small faults. Small faults were found to occur in clusters and the number of faults per foot only weakly correlates to the cumulative displacement of the corresponding faults. The amount of mudstone present is the dominant factor controlling small fault formation. Intervals with only minor quantities of mudstone have the largest number of faults per foot as well as largest associated cumulative displacement per foot. Frequency of occurrence of small faults near the basement is greater when compared to similar lithologies higher in the core. Intensity of small faults do not universally increase with proximity to large faults. To observe an increase in small faults, it is necessary to use a mean global cumulative displacement approach. Zones of greater than average cumulative displacement of small faults in close proximity to large faults were observed in zones that are compatible with faultfault interaction.
4

An investigation of thrust faulting ...

Atherton, Elwood, January 1940 (has links)
Thesis (Ph. D.)--University of Chicago, 1937. / At head of title: The University of Chicago. Lithoprinted. "Private edition, distributed by the University of Chicago libraries."
5

Fault reactivation : the Picuris-Pecos Fault system of north-central New Mexico /

McDonald, David Wilson, January 2003 (has links)
Thesis (Ph. D.)--University of Texas at Dallas, 2003. / Includes vita. "Folded maps in pocket"--P. [3] of cover. Includes bibliographical references (leaves 431-456).
6

The diagnostic features of fault zones from core samples and outcrop study in Hong Kong

Tsang, Hin-sui, Calvin, January 2004 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2004. / Also available in print.
7

Effects of pore pressure variations in critically stressed sandstones

Roeloffs, Evelyn Anne. January 1978 (has links)
Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 30).
8

Some theoretical implications of strike-slip faulting

Petrak, John A. January 1965 (has links)
When a fault occurs in the earth's crust, the ground in its vicinity becomes deformed. This thesis uses the theory of dislocations, as developed by J. A. Steketee, to examine the nature of this deformation for a variety of strike-slip fault models. The theory is developed for calculating the displacement field and stress changes expected at any point around a vertical transcurrent dislocation surface whose net displacement is constant in the horizontal direction, and varies with depth. The results obtained are compared graphically with geodetic data, and those discrepancies that arise between theory and observation are attributed to the limiting assumptions of the model. The principal conclusion of this work is that the variable-slip fault model provides a significant improvement over previous fault models which assumed a constant displacement. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
9

Surficial mapping and kinematic modeling of the St. Clair thrust fault, Monroe County, West Virginia

Sturms, Jason M. January 2008 (has links)
Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains vii, 84 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 75-78).
10

New tests and test methodologies for scan cell internal faults

Yang, Fan 01 December 2009 (has links)
Semiconductor industry goals for the quality of shipped products continue to get higher to satisfy customer requirements. Higher quality of shipped electronic devices can only be obtained by thorough tests of the manufactured components. Scan chains are universally used in large industrial designs in order to cost effectively test manufactured electronic devices. They contain nearly half of the logic transistors in large industrial designs. Yet, faults in the scan cells are not directly targeted by the existing tests. The main objective of this thesis is to investigate the detectability of the faults internal to scan cells. In this thesis, we analyze the detection of line stuck-at, transistor stuck-on, resistive opens and bridging faults in scan cells. Both synchronous and asynchronous scan cells are considered. We define the notion of half-speed flush test and demonstrate that such new tests increase coverage of internal faults in scan cells. A new set of flush tests is proposed and such tests are applied at higher temperatures to detect scan cell internal opens with a wider range of resistances. We also propose new scan based tests to further increase the coverage of those opens. The proposed tests are shown to achieve the maximum possible coverage of opens in transistors internal to scan cells. For an asynchronous scan cell considered, two new flush tests are added to cover the faults that are not detected by the tests for synchronous scan cells. An analysis of detection of a set of scan cell internal bridging faults is described. Both zero-resistance and nonzero-resistance bridging fault models are considered. We show that the detection of some zero-resistance non-feedback bridging faults requires two-pattern tests. We classify the undetectable faults based on the reasons for their undetectability. We also propose an enhanced logic BIST architecture that accomplishes the new flush tests we propose to detect scan cell internal opens. The effectiveness of these new methods to detect scan cell internal faults is demonstrated by experimental results using some standard scan cells from a large industrial design.

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