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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.
31

Reservoir characterization through the application of seismic attributes : multiattribute and unsupervised seismic facies analyses

Marroquín Herrera, Iván Dimitri January 2007 (has links)
Seismic attributes are a descriptive and quantifiable characteristic of seismic data, and so they represent subsets of the total information contained in the original seismic data. Consequently, seismic attrjbutes can be important qualitative and quantitative predictors of physical reservoir properties. Seismic attribute analysis began with the search for bright spots in the late 1960s and early 1970s. Subsequent work in the last decades has established seismic attribute analysis as a valuable tool in reservoir characterization studies. I present in this thesis two seismic attribute analyses for the interpretation of the characteristics of the seismic trace to predict significant geological features (e.g., lithology, rock properties and/or fluid content). The first study is an example of the applicability of seismic attributes to predict geologic controls on production data in a coal bed methane reservoir. Based on the calibration of log data with seismic data procedure, I defined a window of analysis, from which I computed amplitude, frequency and phase related attributes. Then, I used a quantitative multiattribute analysis to derive a seismic attribute-based model that predicts coal thickness. Thereafter, I used with a curvature attribute analysis with the objective to map subtle structural features and predict areas with enhanced permeability. The integration of production data with results achieved from both attribute analyses indicates that best production is associated with thicker coal and the immediate vicinity to seismically defined structures. [...] / Les attributs sismiques ont comme caractéristique de pouvoir décrire et quantifier les données sismiques, de telle manière qu’ils représentent un sous-ensemble de l’information totale contenue dans les données originales. En conséquence, les attributs sismiques peuvent être d’importants paramètres qualitatifs et quantitatifs des propriétés physiques d’un réservoir. L’analyse d’attributs sismiques a commencé avec la prospection de tâches lumineuses (<< bright spots >>) vers la fin des années 1960 et début des années 1970. Des travaux subséquents pendant les dernières décennies ont permis d’établir l’analyse d’attributs sismiques comme un outil valable lors d’études de caractérisation d’un réservoir. Je présente dans cette thèse deux études d’attributs sismiques pour l’interprétation de la forme de la trace sismique afin de prédire des caractéristiques géologiques significatives tels que: la lithologie, les propriétés des roches et/ou le contenu liquide. La première étude est un exemple de l’application d’attributs sismiques pour prédire des contrôles géologiques sur la production d’un réservoir coalbed methane. D’après les résultats de la calibration des diagraphies au câble avec des données sismiques, j’ai défini une fenêtre d’investigation à partir de laquelle des attributs sismiques de type amplitude, fréquence et phase ont été calculés. J’ai utilisé une analyse muIti-attribut pour dériver un model statistique dans le but d’estimer l’épaisseur du réservoir. Par la suite, j’ai utilisé des attributs mesurant la courbature d’une surface pour mettre en relief de subtiles structures géologiques et prédire les régions dans le réservoir avec une perméabilité augmentée. L’intégration des données de production avec les résultats obtenus lors d’analyses d’attributs sismiques indique que la meilleure production est en association avec l’épaississement du réservoir et le voisinage immédiat de structures géologiques. [...]
32

VLSI computing architectures for high speed seismc migration

Kelley, Brian T. 12 1900 (has links)
No description available.
33

An integrated analysis of controlled-and passive source seismic data /

Rumpfhuber, Eva-Maria, January 2008 (has links)
Thesis (Ph. D.)--University of Texas at El Paso, 2008. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
34

An investigation of finite-difference seismic modelling applied to massive sulphide exploration /

Demerling, Christina, January 2004 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2004. / Bibliography: leaves135-137. Also available online.
35

Sources of seismic noise in boreholes

Beydoun, Wafik Bulind January 1982 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Science, 1982. / Microfiche copy available in Archives and Science / Bibliography: leaves 68-69. / by Wafik Bulind Beydoun. / M.S.
36

Seismic damage mechanism at Impala Platinum mine

Ledwaba, Lesiba Shalkie 05 March 2013 (has links)
A dissertation submitted to the Geophysics Department, School of Geosciences, Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Masters of Science. Johannesburg, February 2012 / Impala Platinum Mine (Impala), situated north of the town of Rustenburg in the North West Province of South Africa, has experienced an increase in seismicity from ~841 seismic events in the year 2005 to ~1588 seismic events in 2008. The seismologists and rock engineers need to understand the underlying mechanisms and driving forces responsible for seismicity to develop and design mining layouts and support strategies to lessen the risks posed by rockburts. However, most previous studies of seismicity conducted on Impala and other Bushveld Complex mines in the Rustenburg area provided limited information regarding the source parameters and mechanism due to insufficient data. The study is designed to investigate the seismic hazard on Impala Platinum Mine by means of two approaches: an investigation of seismic source parameters and the mechanism of potentially damaging seismic events, and mapping of the weathered layer of the near surface within the Impala mine lease area. A number of detailed investigations of rockbursts were conducted whereby damage was mapped and photographed. The investigations includes reviews of the seismic history, short-, medium- and long-term seismic hazard assessment methods, and an analysis of the source parameters of the seismic event and associated ground motions. The study has revealed that most of the seismic events occur close to the reef plane, and are the result of the failure of a volume of rock that includes the pillar and the host rock that forms the foundation of the pillar.
37

Reservoir characterization through the application of seismic attributes : multiattribute and unsupervised seismic facies analyses

Marroquín Herrera, Iván Dimitri January 2007 (has links)
No description available.
38

Low porosity mistaken for natural gas hydrate at Alaminos Canyon, Gulf of Mexico: Implications for gas hydrate exploration in marine sediment reservoirs

Tost, Brian Christopher 06 August 2013 (has links)
No description available.
39

Late quaternary depositional and erosional environments of the Louisiana continental shelf: interpretation of fluvial terrain with emphasis on distributary systems from seismic and core data

Unknown Date (has links)
The submerged paleodrainage system of the early Balize delta complex that extended onto the inner continental shelf at 1500 YBP has not been completely studied in great detail. This study interprets the environmental deltaic facies of the Balize Delta, in the Sandy Point region offshore the southeastern Louisiana coast from 120 km of seismic data and 48 vibracores. The stratigraphic and environmental units established in this study provide a geological framework for this area. Overlying Holocene deposits interpreted to be muds of prodelta and lower delta front origin were interpreted as having been deposited from the retreating delta sit atop a transgressive surface, indicated by the toplapping seismic reflectors, the ravinement surface. The deltaic facies below the ravinement surface are of regressive origin an inner shelf delta with widespread delta front sheet sands from a dense group of many distributaries. This research provides a concise methodology adapted from multiple studies for modeling deltaic facies of offshore sand resource targets. / by Zachary Samuel Mester. / Thesis (M.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
40

Analysis and modelling of mining induced seismicity

Bredenkamp, Ben 12 1900 (has links)
Thesis (MScEng (Process Engineering))--University of Stellenbosch, 2006. / Earthquakes and other seismic events are known to have catastrophic effects on people and property. These large-scale events are almost always preceded by smallerscale seismic events called precursors, such as tremors or other vibrations. The use of precursor data to predict the realization of seismic hazards has been a long-standing technical problem in different disciplines. For example, blasting or other mining activities have the potential to induce the collapse of rock surfaces, or the occurrence of other dangerous seismic events in large volumes of rock. In this study, seismic data (T4) obtained from a mining concern in South Africa were considered using a nonlinear time series approach. In particular, the method of surrogate analysis was used to characterize the deterministic structure in the data, prior to fitting a predictive model. The seismic data set (T4) is a set of seismic events for a small volume of rock in a mine observed over a period of 12 days. The surrogate data were generated to have structure similar to that of T4 according to some basic seismic laws. In particular, the surrogate data sets were generated to have the same autocorrelation structure and amplitude distributions of the underlying data set T4. The surrogate data derived from T4 allow for the assessment of some basic hypotheses regarding both types of data sets. The structure in both types of data (i.e. the relationship between the past behavior and the future realization of components) was investigated by means of three test statistics, each of which provided partial information on the structure in the data. The first is the average mutual information between the reconstructed past and futures states of T4. The second is a correlation dimension estimate, Dc which gives an indication of the deterministic structure (predictability) of the reconstructed states of T4. The final statistic is the correlation coefficients which gives an indication of the predictability of the future behavior of T4 based on the past states of T4. The past states of T4 was reconstructed by reducing the dimension of a delay coordinate embedding of the components of T4. The map from past states to future realization of T4 values was estimated using Long Short-Term Recurrent Memory (LSTM) neural networks. The application of LSTM Recurrent Neural Networks on point processes has not been reported before in literature. Comparison of the stochastic surrogate data with the measured structure in the T4 data set showed that the structure in T4 differed significantly from that of the surrogate data sets. However, the relationship between the past states and the future realization of components for both T4 and surrogate data did not appear to be deterministic. The application of LSTM in the modeling of T4 shows that the approach could model point processes at least as well or even better than previously reported applications on time series data.

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