Dissertations / Theses: 'Seismic reflection method. Geology'

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Guy, Erich D. "Analysis and modeling of high-resolution multicomponent seismic reflection data /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486464627806981.

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Lampshire, Laura Dermody. "Crustal structures and the Eastern extent of the Lower Paleozoic Shelf Strata within the Central Appalachians : a seismic reflection interpretation /." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-02162010-020628/.

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Okure, Maxwell Sunday. "Upper mantle reflectivity beneath an intracratonic basin : insights into the behavior of the mantle beneath Illinois basin /." Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd865.pdf.

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Miller, Steven B. "Application of complex trace attributes to reflection seismic data near Charleston, South Carolina." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/50058.

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Complex trace attribute analysis has been applied to 24-fold VIBROSEIS reflection data acquired on the Atlantic Coastal Plain near Charleston, S. C., to yield an expanded interpretation of a Mesozoic basin concealed beneath Coastal Plain sediments. Complex trace attributes express the seismic trace in terms of a complex variable and emphasize different components of the original seismogram. Attributes derived from synthetic seismograms of thin beds are used to interpret the patterns observed on the real data. Complex trace attributes derived from the original seismic trace complement the interpretation of a Mesozoic basin originally imaged by conventional data. The combination of single-sweep recording and use of complex trace attributes is believed to support an interpretation of a transition from basin border conglomerates into finer-grained siltstones nearer to the center of the basin.
Master of Science
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5

O'Neal, Ryan J. "Seismic and well log attribute analysis of the Jurassic Entrada/Curtis interval within the North Hill Creek 3D seismic survey, Uinta Basin, Utah : case history /." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2017.pdf.

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Weisenburger, Kenneth William. "Reflection seismic data acquisition and processing for enhanced interpretation of high resolution objectives." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/74518.

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Reflection seismic data were acquired (by CONOCO, Inc.) which targeted known channel interruption of an upper Pennsylvanian coal seam (Herrin #6) in the Illinois basin. The data were reprocessed and interpreted by the Regional Geophysics Laboratory, Virginia Tech. Conventional geophysical techniques involving field acquisition and data processing were modified to enhance and maintain high frequency content in the signal bandwidth. Single sweep processing was employed to increase spatial sampling density and reduce low pass filtering associated with the array response. Whitening of the signal bandwidth was accomplished using Vibroseis whitening (VSW) and stretched automatic gain control (SAGC). A zero-phase wavelet-shaping filter was used to optimize the waveform length allowing a thinner depositional sequence to be resolved. The high resolution data acquisition and processing led to an interpreted section which shows cyclic deposition in a deltaic environment. Complex channel development interrupted underlying sediments including the Herrin coal seam complex. Contrary to previous interpretations of channel development in the study area by Chapman and others (1981), and Nelson (1983), the channel has been interpreted as having bimodal structure leaving an"island" of undisturbed deposits. Channel activity affects the younger Pennsylvanian sediments and also the unconsolidated Pleistocene till. A limit to the eastern migration of channel development affecting the the Pennsylvanian sediments considered in this study can be identified by the abrupt change in event characteristics.
Master of Science

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7

Calvès, Gérôme. "Tectono-stratigraphic and climatic record of the NE Arabian Sea." Available from the University of Aberdeen Library and Historic Collections Digital Resources. Restricted: no access until Feb., 18, 2010, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=25475.

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8

Chaudhury, Suman. "Marine geophysical studies of the southern margins of the Iberian Peninsula." Thesis, University of Oxford, 1999. http://ora.ox.ac.uk/objects/uuid:1ee8721f-9324-48bd-8d57-b645e02d75fd.

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A wide variety of tectonic settings are juxtaposed at the southern margins of the Iberian Peninsula. The regional geology comprises an Atlantic passive margin in western Iberia, the convergent eastern part of the Azores-Gibraltar plate boundary zone between Africa and Eurasia, and an orogenic arc (the Betic-Rif mountains) surrounding an extensional basin (the Alboran Sea). The complex tectonic history of the southern Iberian margins is recorded in its sediments and structure, and these were investigated in this study using multichannel seismic reflection techniques in conjunction with other marine geophysical data. Multichannel seismic reflection and well data from the Gulf of Cadiz have shown that the earliest sediments are Triassic evaporites, followed by Jurassic carbonates, which form rotated fault blocks in the Gulf of Cadiz. Backstripping and thermal modelling has indicated that a rifting event took place in the Late Jurassic, which stretched the crust by ~20-50%. Gravity modelling, and mapping of stretching factors, has suggested that two zones of thinning underlie the Gulf of Cadiz, which are related to the original rifting event. Backstripped subsidence curves indicate passive margin thermal subsidence until the Miocene, when westward-directed thrusting and loading from the Betic-Rif mountain belt is reflected in a typical foreland basin tectonic subsidence signature of accelerated subsidence with time. A giant, chaotic body of allochthonous sediment was emplaced into the central Gulf of Cadiz as westward migration of the Gibraltar Arc led to oversteepening of the margin west of the Gibraltar Straits, while the Alboran Sea was simultaneously undergoing active extension. These allochthonous deposits are composed mainly of Triassic evaporites and Palaeogene shales. In the Gulf of Cadiz and Seine Abyssal Plains this body has the appearance of an accretionary wedge, but a 300 km long northern lobe of the body extends into the Horseshoe Abyssal Plain. This lobe is interpreted as being a cumulative mass wasting feature, formed by the gravity-driven downslope transport of large allochthonous masses as debris flows and slides and slumps, encouraged by a regional gradient and a pre-existing trough in the Horseshoe Abyssal Plain. The total volume of sediments involved was of the order of 72 000 km 3 , and the time of emplacement has been estimated as being Tortonian on the basis of seismic correlation with core data at DSDP site 135. This chaotic unit has formed a series of longitudinal diapiric ridges in the northern Gulf of Cadiz, which have been interpreted to act as a transport system for gas generated in the lower slope area to migrate to the upper slope where gas-related features are seen. Gas hydrates are present beneath the lower continental slope, as inferred from a bottom-simulating reflection on seismic reflection profiles.

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Calvès, Gérôme. "Tectono-stratigraphic and climatic record of the NE Arabian Sea." Thesis, University of Aberdeen, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=25475.

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This study describes the tectono-stratigraphic and climatic record of the NE Arabian Sea during the Cenozoic. Compilation of regional knowledge and subsurface observations has in this thesis provided new interpretations and insights into the records present along this passive margin. The first is the rifting period (80-65 Ma) and the identification of a syn-rift volcanic sequence, comparable to other volcanic rifted margins. This is followed by the record of a drift sequence (~65 Ma to present day), composed of extensive carbonate platforms and an infill sequence of siliciclastic deposits. The analysed drift sequence (sink) is partly the result of the erosion of the hinterland (source) characterised by the India-Eurasia continent-continent collision. Influence of regional climate and/or tectonic forces on the accumulation rate in the sink was tested, but not conclusive as the study area (Upper Indus Fan) covers only a limited part of the sedimentary record of the Indus Fan. The thermal regime of the western margin of India is sparsely sampled, but once analysed, allows the definition of first order constraints on multiple rifting events. The post-rift subsidence of the margin is slow and anomalous for >28 m.y. after break-up, potentially in relation with vigorous asthenospheric convection and a sharp ocean-continent boundary. Past and present fluid flow is recorded in the sedimentary sequence of the Upper Indus Fan. The first is related to gas hydrate occurrence and is the result of the migration of fluids by a plumbing system to the shallow subsurface, expressed by bottom-simulating reflections crosscutting stratal reflections. A longer term fluid migration is recorded in this basin by the longest lived (~22 m.y.) mud volcano field recorded to date.

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D'Angelo, Richard M. "Correlation of seismic reflection data with seismicity over the Ramapo, New Jersey, fault zone." Thesis, Virginia Tech, 1985. http://hdl.handle.net/10919/45651.

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Reflection seismic data, mylonite reflectivity, gravity data, and earthquake hypocenters have been integrated into a possible explanation for seismicity in the Ramapo fault area. Seven reflection seismic lines were processed using variations in sorting and residual statics. Single VIBROSEIS sweeps were treated as separate sourcepoints. Compressional velocities and densities were determined in the laboratory. Reflection coefficients and gravity models provide evidence for reflections from mylonite zones. Earthquake hypocenters were projected into the vertical seismic sections. The results suggest a correlation between rock volumes containing hypocenters and rock volumes containing mylonite zones. The seismic line furthest from the Taconic suture displays fewer hypocenters and mylonites, in agreement with an assumed model of mylonite development possibly associated with obduction of continental crust. The mylonite zones in the basement may serve as local areas of crustal weakness for seismic activity occurring in the area.

Master of Science

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Roberts, Brian J. "A broadside and end-on seismic experiment on the crustal structure of the Newfoundland Appalachians /." Internet access available to MUN users only, 1998. http://collections.mun.ca/u?/theses,23082.

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Burton, Andrew Joseph. "Seismic imaging methods applied to Devonian carbonate reef environments of western Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0003/MQ42356.pdf.

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Gresko, Mark J. "Analysis and interpretation of compressional (P-wave) and shear (SH-wave) reflection seismic and geologic data over the Bane Dome, Giles County, Virginia." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/53879.

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Approximately 37 km of predominantly 24-fold P-wave Vibroseis data and 16 km of 24-fold SH-wave Vibroseis data were acquired in the southern portion of the folded Appalachians near the Bane Dome in Giles County, Virginia. Data processing techniques included the application of newly developed methods for crossdip removal as well as the determination of statics solutions in the case of time variant shifts within the data traces. Minimum-phase filter deconvolution was also applied for the removal of reverberating energy and multiples recorded on the SH—wave lines. V_p/V_s ratios were used to aid in the determination of lithologies in the absence of bore-hole data. Interpreted thickening of the Lower Cambrian to Upper Precambrian sequence beneath the Bane Dome appears to represent Eocambrian rifting. Faults generated at that time may now be reactivated by the present stress regime, causing earthquake activity in this area. Interpretation of the seismic data supports a duplex structure proposed for the Paleozoic rocks of the Bane Dome Complex within the Narrows thrust sheet of southwestern Virginia.
Ph. D.

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Brennan, Jeanne L. "Interpretation of Vibroseis reflections from within the Catoctin Formation of central Virginia." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/76030.

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Large amplitude seismic reflections from within the Catoctin Formation of central Virginia are interpreted to originate from acoustically thin beds of interlayered metabasalts and metasediments. Large acoustic impedance contrasts exist between epidotised layers ( epidosites and volcanic breccia) and non-epidotised layers (greenstones and phyllites) within the Catoctin Formation. Acoustic impedance contrasts also exist between greenstones (metabasalts) and phyllites (metasediments). Constructive interference of small amplitude reflections from thin beds result in large amplitude, reverberating reflections. Thin bed reflections that approximate the first derivative of the source wavelet constructively interfere to give even larger amplitude reflections than those originating by conventional tuning. Computer modeling based on two geologic sections of thin beds of epidosites interlayered with greenstones and of greenstones interlayered with phyllites and epidosites indicates that large amplitude reflections result from constructive interference of thin bed reflections.
Master of Science

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15

Rucker, Clara Rose. "CONSTRAINING BOUNDARIES AND EXTENT OF THE CHARLESTON UPLIFT, NORTHEAST NEW MADRID SEISMIC ZONE, USING SHALLOW SEISMIC REFLECTION METHODS." UKnowledge, 2017. http://uknowledge.uky.edu/ees_etds/50.

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A recently identified 30 km by 7.2 km subsurface stratigraphic uplift, called the Charleston uplift, exhibits 36 m offset of Paleogene-Quaternary unconformity based on shallow borehole data. Two seismic soundings demonstrated relief in Paleozoic and Cretaceous reflectors across the northern boundary of the uplift, suggesting a structural origin rather than an erosional origin. This study collected and analyzed 18 additional shallow seismic soundings to confirm Paleozoic and Cretaceous offset across the boundaries of the uplift, to better constrain the surface trace of the uplift, and to examine potential extension into western Kentucky. One ground penetrating radar profile was taken in western Kentucky to image recent deformation. Results confirm Paleozoic and Cretaceous offset along the boundaries of the uplift and indicate extension of the uplift into western Kentucky, although recent deformation was unconfirmed by the radar profile. These data support a structural origin. The N46°E trend of the uplift as well as its coincidence with contemporary microseismicity suggest that this feature may be related to the New Madrid seismic zone, specifically the New Madrid North fault, which may have implications for hazard assessment, as well as possible a reevaluation of the epicenters for the 23 January 1812 Mw ≥ 7.0 event.

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Tingey, Brady E. "Detection of a Landslide Glide Plane Using Seismic Reflection Methods: Investigation at Little Valley Landslide in Draper, Utah." BYU ScholarsArchive, 2006. https://scholarsarchive.byu.edu/etd/1290.

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An integration of geological and geophysical techniques has been used to characterize the internal structure of the Little Valley Landslide in Draper, Utah, USA. The Little Valley Landslide is a pre-historic landslide as old as 13ka B.P. It is found to consist of chaotic and disturbed weathered volcanic units derived from Tertiary age volcanics that comprise a great portion of the Wasatch Range. Geotechnical investigations that were integrated with the geophysical results included excavation of trenches and drilling of boreholes. Geophysical methods, in particular high-resolution seismic data, were used to provide a framework for interpreting the geotechnical observations. High-resolution seismic reflection data, seldom used in landslide investigations, were acquired and processed in order to image the basal or glide surface of the landslide and the structure underlying the landslide. The integration of the geotechnical and geophysical investigations provided a better understanding of the geometry of a portion of the Little Valley Landslide. Trenching and drilling identified landslide material in the subsurface. The high-resolution seismic reflection data imaged the glide surface with the onset of coherent reflectivity. A decollement or glide surface underlies the landslide indicating a large mass movement. The glide surface is observed on the seismic reflection profiles to be deepest in the center portion of the landslide. It is observed in the seismic reflection images to shallow up slope and creating a trough-like shape feature. A contour map modeling the middle of the Little Valley Landslide is derived from the seismic data. This study shows that seismic reflection techniques can be successfully used in complex alpine landslide regions. They are also efficient and cost-effective tools when compared to trenching and drilling investigations. The seismic data can (1) provide a framework to link geological data and (2) take the place of an extensive trenching and drilling program.

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South, John V. "Investigating the margins of Pleistocene lake deposits with high-resolution seismic reflection in Pilot Valley, Utah." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2648.pdf.

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Okojie-Ayoro, Anita Onohuome. "An Approach to Mapping of Shallow Petroleum Reservoirs Using Integrated Conventional 3D and Shallow P- and SH-Wave Seismic Reflection Methods at Teapot Dome Field in Casper, Wyoming." BYU ScholarsArchive, 2007. https://scholarsarchive.byu.edu/etd/1219.

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Using the famous Teapot Dome oil field in Casper, Wyoming, USA as a test case, we demonstrate how high-resolution compressional (P) and horizontally polarized shear (SH) wave seismic reflection surveys can overcome the limitations of conventional 3D seismic data in resolving small-scale structures in the very shallow subsurface (< 100-200 m (~328-656 ft)). We accomplish this by using small CMP intervals (5 ft and 2.5 ft, respectively) and a higher frequency source. The integration of the two high-resolution seismic methods enhances the detection and mapping of fine-scale deformation and stratigraphic features at shallow depth that cannot be imaged by conventional seismic methods. Further, when these two high-resolution seismic methods are integrated with 3D data, correlated drill hole logs, and outcrop mapping and trenching, a clearer picture of both very shallow reservoirs and the relationship between deep and shallow faults can be observed. For example, we show that the Shannon reservoir, which is the shallowest petroleum reservoir at Teapot Dome (depth to the top of this interval ranging from 76-198 m (250-650 ft)) can only be imaged properly with high-resolution seismic methods. Further, northeast-striking faults are identified in shallow sections within Teapot Dome. The strike of these faults is approximately orthogonal to the hinge of Teapot Dome. These faults are interpreted as fold accommodation faults. Vertical displacements across these faults range from 10 to 40 m (~33 to 131 ft), which could potentially partition the Shannon reservoir. The integration of 3D and high-resolution P-wave seismic interpretation helped us determine that some of the northeast-striking faults relate to deeper faults. This indicates that some deeper faults that are orthogonal to the fold hinge cut through the shallow Shannon reservoir. Such an observation would be important for understanding the effect on fluid communication between the deep and shallow reservoirs via these faults. Furthermore, the high-resolution seismic data provide a means to better constrain the location of faults mapped from drill hole logs. Relocation of theses faults may require re-evaluation of well locations as some attic oil may have not been drained in some Shannon blocks by present well locations. Therefore our study demonstrates how conventional 3D seismic data require additional seismic acquisition at smaller scales in order to image deformation in shallow reservoirs. Such imaging becomes critical in cases of shallow reservoirs where it is important to define potential problems associated with compartmentalization of primary production, hazard mitigation, enhanced oil recovery, or carbon sequestration.

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Mojica, Moncada Jhon Fredy. "Estrategias del procesado y análisis espectral de datos sísmicos para el estudio de procesos dinámicos en oceanografía física." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/334973.

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La circulación oceánica de gran escala se encuentra relacionada con la pequeña escala a través de los procesos turbulentos, los cuales hacen posible el intercambio de energía cinética. Alrededor de la frecuencia de Coriolis, el efecto cinemático dominante es el campo de los giros geostróficos, mientras que a mayores frecuencias y especialmente cerca de la frecuencia inercial, los movimientos están dominados por la dinámica de las ondas internas, cuya propagación en el océano transfiere la energía a menores escalas a través de procesos de dispersión y de interacción onda-onda. Dependiendo de las condiciones oceanográficas, cuando las ondas internas rompen, generando como consecuencia, la transferencia de parte de su energía a las escalas más pequeñas mediante procesos de mezcla irreversible. Actualmente los mecanismos de transferencia de energía entre los distintos sub-rangos, se comprenden solo parcialmente. Esto es debido principalmente al vacío observacional existente en el rango espacial intermedio (-101 — 103 m). Esta falta de observaciones directas ha motivado que se hayan planteado diferentes modelos teóricos para explicar los mecanismos y rutas de transferencia, como por ejemplo los modelos de interacción onda-onda a nivel meso-escalar hasta escalas disipativas, las inestabilidades, y la interacción con la topografía. En este trabajo se presenta evidencia observacional indicando que la cascada energética en la termoclina del Mar de Alborán sigue la ruta de las inestabilidades. Esta se caracteriza por el intercambio de aguas Atlánticas y aguas Mediterráneas destacando su interfaz entre los 35 m y 110 m según datos hidrográficos registrados. En particular, se muestra que el rompimiento de las ondas internas está causado por el desarrollo de inestabilidades de cizalla como las de Kelvin-Helmholtz (K-H) siendo consistentes con los valores de variables oceanográficas determinadas a partir de medidas directas (número de Richardson < —0.25). Estos resultados innovadores se basan en el análisis espectral del desplazamiento vertical de reflectores acústicos registrados por primera vez con un sistema de sísmica multicanal de alta resolución (HR-MCS), que proporciona una cobertura espectral completa entre escalas de 103 m y 10 m en dirección horizontal y una resolución de unos 2 m en dirección vertical. Para el análisis se han utilizado datos de HR-MCS adquiridos durante la campaña de prospección geológica IMPULS-2006. El espectro energético del desplazamiento vertical de los reflectores (El), se ha calculado de forma análoga a otros estudios previos obtenidos con equipos sísmicos de menor resolución. Un punto clave para comparar las pendientes espectrales con estimaciones teóricas de la energía es que las ondulaciones de los reflectores acústicos reproduzcan el desplazamiento vertical de las isopicnas. Se asume que esta condición es válida para la zona de estudio, ya que ésta no se encuentra afectada por intrusiones salinas o de temperatura. A nivel mesoescalar, el espectro energético de las ondulaciones de los reflectores sigue el modelo de Garrett-Munk (1979) para ondas internas, que predice una pendiente espectral con valor -2. De acuerdo a la teoría y a simulaciones numéricas de alta resolución, el sub-rango transicional es asociado a las inestabilidades de cizalla en general, y a las de K-H en particular, debe presentar pendientes espectrales entre los -2.5 y -3.0. Este rango de pendientes es consistente con la pendiente espectral calculada en el rango de escalas intermedio (100 – 35 m), donde se obtiene un valor promedio de -2.8. Finalmente el modelo de Batchelor, que describe el sub-rango inercial a menores escalas predice que la pendiente espectral en este rango debe ser - 5/3. El análisis espectral muestra pendientes próximas a este valor (-1.64), a partir de los ~35 m, lo que sugiere que a estas escalas los vórtices laminares ya han colapsado y la dinámica empieza a ser dominada por procesos turbulentos. A partir de los valores obtenidos en la caracterización espectral, se ha determinado el nivel de mezcla generado para cada uno de los rangos espaciales. Los valores obtenidos se ajustan a los niveles de mezcla medidos directamente en la cuenca de Alborán con equipos hidrográficos convencionales, confirmando la validez del sistema HR-MCS para la identificación y caracterización de estructuras y procesos oceanográficos a escalas intermedias. Los parámetros de mezcla obtenidos con el sistema de sísmica HR-MCS, pueden contribuir en la mejora de los modelos predictivos de procesos relacionados con la dinámica oceánica, debido a su alto nivel de sinopticidad, alta resolución lateral y amplio rango de escalas, abarcando desde la mesoescala hasta la estructura fina
This work presents observational evidence clearly indicating that the energy cascade in the Alboran Sea thermocline follows the instability route. In particular we show that the internal wave breaking is due to the development of shear instabilities, and in particular Kelvin-Helmholtz (K-H) like ones. These innovative results are based on the spectral analysis of the acoustic reflectors vertical displacement recorded for the first time with a high resolution multichannel seismic system (HR-MCS), which provides a full spectral coverage between 103 m and 10 m in horizontal direction, and 2 m in vertical direction. Our analysis is based on HR-MCS data recorded in the IMPULS-2006 geological survey. The vertical displacement energy spectra of reflectors were calculated following a similar approach to that of previous studies using lower resolution seismic data. A key point to compare the spectral slopes with theoretical energy estimations is that the acoustic reflectors undulations reproduce the isopycnals vertical displacement. This is a reasonable assumption in our study area, since the Alboran Sea not subject to salinity-temperature compensating intrusions. At mesoscale level, the energy spectra of the reflectors undulation follows the Garret-Munk (1979) model, which predicts a power law spectral density with value -2. The calculated spectra show this slope value at scales larger than circa 100 m, near to the buoyancy scale calculated from oceanographic measurements (l(nh) aprox. Equal to 93m). Thus, we deduce that this spectral range corresponds to the internal waves regime in the mesoscale range. According to theory and high resolution numerical simulations, the transitional sub-range is associated in general to shear instabilities, and particularly to K-H instabilities that should display steeper spectral slopes between -2.5 and -3.0. This spectral slope range agrees with the slope calculated at the intermediate scale range (100 - 35 m), where the mean value is -2.8. A feature of the K-H structures is the laminar vortex shape, with a horizontal scale an order higher than vertical (used to be a ratio of 7/1) which also agrees with the seismic observations. Finally the Batchelor model, which is the most accepted model to describe the inertial sub-range at the smallest scales, predicts a spectral slope of -5/3. Our spectral analysis show slopes at this value (-1.64), from wavelengths smaller than circa 35 m, which suggest that the laminar vortex have collapsed and the dynamics starts to be dominated by turbulent processes. The mixing parameters obtained from HR-MCS data, can contribute to the improvement of the oceanic dynamic modelling, thanks to their high level of sinopticity, high lateral resolution and wide range of scales, covering from mesoscale to finestructure.

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20

Gigandet, Katherine M. "Processing and Interpretation of Illinois Basin Seismic Reflection Data." Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1401309913.

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21

Schorr, Gregory Thomas. "Study of seismic reflection data over Virginia Mesozoic basins." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/91064.

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Studies of Vibroseis reflection profiles over the exposed Triassic-Jurassic Culpeper, Richmond, and Scottsville Basins, and another profile over a probable early Mesozoic basin (Toano) beneath the Atlantic Coastal Plain sediments, in Virginia indicate that resolution of the geometry of the basins is inhibited by small impedance contrasts between the rock units within the basin and those bordering the basin. None of the seismic sections exhibit reflections which can be directly attributed to a Triassic-pre-Triassic interface. Resolution of the geometry of the basin sediments depends upon the presence of anomalously high or low velocity/density rock units within the basin, and similarly the presence of large amplitude reflections from within these and possibly other basins may imply the presence of these units, which include basalt and lignite. A method of analyzing the refracted waves in the seismic reflection data with large receiver offsets for determination of apparent velocities and the geometry of the refraction interface is presented. The Culpeper seismic lines indicate a basin with a maximum thickness of 2500 m along the western side and approximately 1750 m along the eastern side of the basin. The maximum thickness of the Richmond Basin below the seismic line is approximately 2700 m. The Scottsville Basin contains sedimentary strata with a thickness of 1750 m and the seismic data from the Toano Basin indicate a thickness of 3000 m. The compressional wave velocity of the strata within these basins has a range of 4000-5300 m/sec.
M.S.

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22

Pickup, Simon Lee Barton. "Rifted margin development of West Iberia from deep seismic reflection profiles." Thesis, Royal Holloway, University of London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286364.

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23

Ecevitoglu, Berkan G. "Velocity and Q from reflection seismic data." Diss., Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/77793.

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This study has resulted in the discovery of an exact method for the theoretical formulation of the effects of intrinsic damping where the attenuation coefficient, a(v), is an arbitrary function of the frequency, v. Absorption-dispersion pairs are computed using numerical Hilbert transformation; approximate analytical expressions that require the selection of arbitrary constants and cutoff frequencies are no longer necessary. For constant Q, the dispersive body wave velocity, p(v), is found to be p(v) = (p(v_N)/(1+(1/2Q H(-v)/v)) where H denotes numerical Hilbert transformation, p(v) is the phase velocity at the frequency v, and p(v_N) is the phase velocity at Nyquist. From (1) it is possible to estimate Q in the time domain by measuring the amount of increase, ΔW, of the wavelet breadth after a traveltime, Q=(2Δ𝛕)/(𝝅ΔW) The inverse problem, i.e., the determination of Q and velocity is also investigated using singular value decomposition (SVD). The sparse matrices encountered in the acquisition of conventional reflection seismology data result in a system of linear equations of the form AX = B, with A the design matrix, X the solution vector, and B the data vector. The system of normal equations is AᵀAX = AᵀB where the least-squares estimate of X = X = V(1/S)UᵀB and the SVD of A is A = USVᵀ. A technique to improve the sparsity pattern prior to decomposition is described. From an application of equation (2) using reference reflections from shallower reflectors, crystalline rocks in South Carolina over the depth interval from about 5 km to 10 km yield values of Qin the range Q = 250 - 300. Non-standard recording geometries ( "Q-spreads") and vibroseis recording procedures are suggested to minimize matrix sparseness and increase the usable frequency bandwidth between zero and Nyquist. The direct detection of body wave dispersion by conventional vibroseis techniques may be useful to distinguish between those crustal volumes that are potentially seismogenic and those that are not. Such differences may be due to variations in fracture density and therefore water content in the crust.
Ph. D.

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Martínez, Loriente Sara. "Geophysical and geological characterization of the active structures and of the nature of the basement in the Eurasia-Africa plate boundary (SW Iberian Margin): Implications for regional geodynamics and seismic hazard assessment = Caracterització geofísica i geològica de les estructures actives i la natura del basament en el límit de plaques Euràsia-Àfrica (Marge SO d’Ibèria): Implicacions per la geodinàmica regional i per l’avaluació de la perillositat sísmica." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/132537.

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In this PhD Thesis I present a new interpretation of: 1) active structures implicating old oceanic lithosphere; 2) the nature of the basement; and 3) the distribution of the basement domains and the geodynamic reconstruction of the SW Iberian margin, a region that hosts the slow convergent boundary between the African and Eurasian plates. This interpretation is based on new geophysical data acquired, processed and modeled in the framework of this PhD work. The main findings of my study are the following ones: 1) Recently acquired high-resolution multichannel seismic profiles together with bathymetric and sub-bottom profiler data (SWIM 2006 survey) from the external part of the Gulf of Cadiz (Eurasia-Africa plate boundary) reveal active deformation involving old (Mesozoic) oceanic lithosphere [Martínez-Loriente et al., 2013]. This dataset shows active strike-slip occurring along the prominent lineaments North and South, imaging seafloor displacements and active faulting to depths of at least 10 km and of a minimum length of 150 km [Bartolome et al., 2012]. Seismic moment tensors show predominantly WNW–ESE right-lateral strike-slip motion [Geissler et al., 2010]. Estimates of earthquake source depths close to the fault planes indicate upper mantle (i.e., depths of 40–60 km) seismogenesis [Stich et al., 2010, Bartolomé et al., 2012], implying the presence of old, thick, and brittle lithosphere. Moreover, the SWIM 2006 dataset also reveals E-W trending dextral strike-slip faults showing surface deformation of flowerlike structures, which predominate in the Horseshoe Abyssal Plain. In contrast, NE-SW trending compressive structures prevail in the Coral Patch Ridge and in the Seine Hills [Martínez-Loriente et al., 2013]. Although the Coral Patch Ridge region is characterized by subdued seismic activity, the area is not free from seismic hazard. Most of the newly mapped faults correspond to active blind thrusts and strike-slip faults that are able to generate large magnitude earthquakes (Mw 7.2 to 8.4) [Martínez-Loriente et al., 2013]. 2) Combined seismic and gravity modeling along NEAREST profile P1 acquired in the external part of the SW Iberian margin, reveals the presence of a serpentinized peridotite basement flooring the Gorringe Bank and adjacent sectors of the Tagus and Horseshoe abyssal plains [Sallarès et al., 2013]. These three domains would be part of a wide ultramafic rock band [Sallarès et al., 2013], similar to the Zone of Exhumed Continental Mantle off Western Iberia [Pinheiro et al., 1992; Dean et al., 2000]. Furthermore, the basement velocity structure of the southeastern part of the profile (i.e., the Coral Patch Ridge and Seine Abyssal Plain) indicates the presence of a highly heterogeneous, thin oceanic crust (4-6 km-thick), similar to that described in slow/ultraslow spreading centers, with local high-velocity anomalies possibly representing serpentinite intrusions [Martínez-Loriente et al., submitted]. 3) The integration of the results from NEAREST profiles P1 and P2 that runs across the central Gulf of Cadiz [Sallarès et al., 2011], and previously existing data reveals the presence of three main oceanic domains offshore SW Iberia [Martínez-Loriente et al., submitted]: (a) the Seine Abyssal Plain domain, made of oceanic crust that would be generated during the first slow (~8 mm/yr) stages of seafloor spreading of the northeastern segment of the Central Atlantic (i.e. 190 Ma – 180 Ma) [Martínez-Loriente et al., submitted]; (b) the Gulf of Cadiz domain, constituted of oceanic crust generated in the Alpine-Tethys spreading system between Iberia and Africa, which was coeval with the formation of the Seine Abyssal Plain domain and lasted up to the North Atlantic continental break-up (Late Jurassic) [Sallarès et al., 2011]; and (c) the Gorringe Bank domain, made of exhumed mantle rocks that was probably generated during the earliest phase of the North Atlantic opening that followed the continental crust breakup (Early Cretaceous) [Sallarès et al., 2013]. During the Miocene, the NW–SE trending Eurasia–Africa convergence resulted in thrusting of the southeastern segment of the exhumed serpentinite band over the northwestern one, forming the Gorringe Bank [Sallarès et al., 2013]. These models indicate that the Seine Abyssal Plain and Gulf of Cadiz domains are separated by the Lineament South strike-slip system, whereas the Gulf of Cadiz and Gorringe Bank domains are bounded by a deep thrust fault system located at the center of the Horseshoe Abyssal Plain, which we refer to as the Horseshoe Abyssal plain Thrust [Martínez-Loriente et al., submitted]. These new findings are relevant for geohazard assessment in the region. On one hand, the presence of active deformation has been demonstrated in the external part of the Gulf of Cadiz, involving structures considered inactive [e.g. Zitellini et al., 2009] until the present work. On the other hand, the knowledge of the nature of the SW Iberian margin basement may provide valuable information into the process of seismogenesis, such as earthquake nucleation and velocity propagation. Both aspects will help to refine regional seismic and tsunami hazard assessment models.
El Margen SO de Iberia es una zona de gran interés dónde han tenido lugar grandes terremotos y tsunamis, como el de Lisboa de 1755 (Mw 8.5) o el de Horseshoe de 1969 (Mw 8.0). La convergencia NO-SE entre las placas de África y Eurasia controla la actividad sísmica de moderada magnitud que caracteriza la región. Datos de sísmica de reflexión multicanal adquiridos recientemente, junto con datos batimétricos y perfiles de alta resolución (campaña SWIM 2006; IP: Eulàlia Gràcia) de la parte externa del Golfo de Cádiz (límite de placas Eurasia- África), revelan deformación activa involucrando litosfera oceánica antigua (Mesozoico). Estos conjuntos de datos muestran deformación en dirección a lo largo de dos lineaciones prominentes (la Lineación Norte y la Lineación Sur), se observan desplazamientos del fondo marino y fallamiento activo a profundidades de 10 km y con una longitud mínima de 150 km [Bartolomé et al., 2012]. Además los datos de SWIM revelan fallas de strike-slip orientadas E-W mostrando deformación en superficie en forma de estructuras en flor. También se observan estructuras compresivas de dirección NE-SO en la zona del Coral Patch Ridge y de las Seine Hills [Martínez-Loriente et al., 2013]. Pese a que la región se caracteriza por una sismicidad muy débil, los datos demuestran que hay deformación activa. Muchas de las nuevas estructuras cartografiadas corresponden a cabalgamientos ciegos y estructuras en dirección que son capaces de generar grandes terremotos (Mw 7.2 ¿ 8.4) y consecuentes tsunamis [Martínez-Loriente et al., 2013]. Los modelos de tomografía y gravimetría a lo largo del perfil NEAREST P1 adquirido en la parte externa del Margen SO de Iberia, revelan la presencia de peridotita serpentinizada en el basamento del Gorringe Bank y los sectores adyacentes de las llanuras abisales de Tagus y Horseshoe [Sallarès et al., 2013]. Estos tres dominios formarían parte de una banda de rocas ultramáficas, la cual se habría generado probablemente durante la primera fase de la abertura del Atlántico Norte (Cretácico Inferior) [Sallarès et al., 2013]. La estructura de velocidad en la parte sur del perfil, indica la presencia de una corteza oceánica delgada y muy heterogénea, similar a la descrita en zonas de generación de corteza lenta o muy lenta [Martínez-Loriente et al., submitted]. Esta corteza oceánica delgada se habría formado durante la primera fase lenta (8 mm/año) de generación de corteza en el segmento NE del Atlántico Central (190-180 Ma) [Martínez-Lorietne et al., submitted]. La integración de los resultados de los perfiles NEAREST P1 y P2 [Sallarès et al., 2011], junto con datos previamente publicados, revelan la presencia de 3 dominios oceánicos en el Margen SO de Iberia: (1) El dominio de la Llanura abisal del Seine, generada durante los primeros episodios de generación de corteza oceánica del segmento NE del Atlántico Central; (2) el dominio del Golfo de Cádiz, compuesto por corteza oceánica generada en el sistema de expansión Alpino-Tethys entre Iberia y África, el cual es sincrónico con la formación del dominio anterior; (3) el dominio del Gorringe Bank, compuesto por rocas del manto exhumadas, formadas durante las primeras fases de la abertura del Atlántico Norte. Estos modelos indican que la Llanura abisal del Seine y el Golfo de Cádiz están separadas por la Lineación Sur, mientras que el Golfo de Cádiz y el Gorringe Bank están separados por un sistema de falla profunda localizado en el centro de la llanura de Horseshoe, al cual nos referimos como el cabalgamiento de la llanura abisal de Horseshoe [Martínez-Loriente et al., submitted]. Estos nuevos descubrimientos son relevantes para los estudios de peligrosidad sísmica en la región. Por un lado, la presencia de deformación activa ha sido demostrada en la parte externa del Golfo de Cádiz, involucrando estructuras consideradas hasta el momento como inactivas [Zitellini et al., 2009]. Por el otro lado, el conocimiento de la naturaleza del basamento en el Margen SO de Iberia puede proporcionar información muy valiosa en el proceso de sismogénesi, como la nucleación de terremotos y la velocidad de propagación. Ambos aspectos pueden ayudar a refinar los modelos de evaluación del riesgo sísmico y de tsunamis.

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Lau, Chi-tong Andy. "Marine geological model in Mirs Bay, NE Hong Kong, using marine seismic reflection." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B40722405.

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Guy, Erich D. "Analysis and modeling of high-resolution multicomponent seismic reflection data." Columbus, Ohio : Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1044983175.

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Thesis (Ph. D.)--Ohio State University, 2003.
Title from first page of PDF file. Document formatted into pages; contains xxxviii, 372 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: Jeffrey J. Daniels, Dept. of Geological Sciences. Includes bibliographical references (p. 362-372).

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Rutledge, III Frederick Alexander. "HIGH RESOLUTION GEOPHYSICAL INVESTIGATION OF LATE QUATERNARY DEFORMATION IN THE LOWER WABASH VALLEY FAULT SYSTEM." UKnowledge, 2004. http://uknowledge.uky.edu/gradschool_theses/294.

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Seven and a half kilometers of high-resolution SH-wave seismic reflection profiles were collected across the Mt. Vernon graben, a 35 km by 3 km graben (bounded by the Wabash Island (WIF) and Hovey Lake faults (HLF)) in the southern Wabash Valley fault system (WVFS) of southern Indiana. Forty-six discrete faults were imaged that displaced Quaternary horizons in the vicinity of the WIF and HLF. The structural styles associated with faults include: 1) normal displacement, 2) reverse displacement and other compressional features, 3) varying magnitudes of slip along fault planes, and 4) different senses of slip along individual fault planes. Carbon 14 dating of displaced horizons suggests movement between approximately 26,000 and 42,000 YBP. The style and timing of Quaternary deformation within the WVFS, the close association of soil faults to documented post-Pennsylvanian bedrock faults (HLF and WIF), and focal mechanism studies of current seismicity in the Wabash Valley seismic zone are all direct evidence that the extensionally-formed faults of the WVFS are being transpressionally reactivated: a manner consistent with the current east-northeast westsouthwest regional compressive stress field.

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Nautiyal, Atul. "Aspects of spatial wavelets and their application to modelling seismic reflection data." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26504.

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The propagation of seismic waves may be described in the space-frequency domain by the Rayleigh-Sommerfeld convolution integral. The kernel of this integral is called a spatial wavelet and it embodies the physics and geometry of the propagation problem. The concepts of spatial convolution and spatial wavelet are simple and are similar to other topics studied by geophysicists. With a view to understanding these concepts, some aspects of spatial wavelets and their application to two-dimensional, zero-offset, acoustic seismic modelling were investigated. In studying the spatial wavelet, two topics in particular were examined: spatial aliasing and wavelet truncation. Spatial aliasing arises from the need to compute a discrete wavelet for implementation on a computer. This problem was solved by using an analytic expression for the spatial wavelet in the Fourier (wavenumber) domain. In the wavenumber domain the wavelet was windowed by a fourth order Butterworth operator, which removed aliasing. This technique is simple and flexible in its use. The second problem of wavelet truncation is due to the necessity of having a wavelet of finite length. A length limiting scheme based upon on the energy content of a wavelet was developed. It was argued that if that if a large portion of the wavelet energy was contained in a finite number of samples, then truncation at that sample would incur a minimal loss of information. Numerical experiments showed this to be true. The smallest length wavelet was found to depend on temporal frequency, medium velocity and extrapolation increment. The combined effects of these two solutions to the practical problem of computing a spatial wavelet resulted in two drawbacks. First, the wavelets provide modelling capabilities up to structural dips of 30 degrees. Second, there is a potential for instability due to recursive application of the wavelet. However, neither of these difficulties hampered the modelling of fairly complex structures. The spatial wavelet concept was applied to seismic modelling for media of varying complexity. Homogeneous velocity models were used to demonstrate diffraction evolution, dip limitations and imaging of curved structures. The quality of modelling was evaluated by migrating the modelled data to recover the time-image model of the reflection structure. Migrations of dipping and synform structures indicated that the modelled results were of a high calibre. Horizontally stratified velocity models were also examined for dipping and synform structures. Modelling these reflection structures showed that the introduction of a depth variable velocity profile has a tremendous influence on the synthetic seismic section. Again, migration proved that the quality of the data was excellent. Finally, the spatial wavelet algorithm was extended to the case of laterally varying velocity structures. The effects of space variant spatial convolution in the presence of a smoothed velocity field were examined. Smoothed velocity fields were computed by a simple weighted averaging procedure. The weighting function used was a decaying exponential whose decay rate determined the amount of smoothing. Seis-mograms computed for this case showed that the algorithm gave smoother and more continuous reflection signatures when the velocity field has been smoothed so that the largest lateral velocity gradient corresponded to the lower end of the temporal frequency band of the spatial wavelets. In this respect, the results are similar to those of geometric ray theory. Also, the travel times of these models compared favourably with those of ray tracings.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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Pappano, Phillip A. "Structure and regional tectonic setting across the Atlantic Coastal Plain of northeastern Virginia as interpreted from reflection seismic data." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09122009-040224/.

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Rumpfhuber, Eva-Maria. "An integrated analysis of controlled-and passive source seismic data /." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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Jiao, Junru. "Residual migration velocity analysis in the plane wave domain : theory and applications /." Access restricted to users with UT Austin EID Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3023551.

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Peterman, David Joseph. "Seismic Reflection Profiling near Middletown, Ohio and Interpretation of Precambrian Deformational Settings." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1463936515.

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劉志棠 and Chi-tong Andy Lau. "Marine geological model in Mirs Bay, NE Hong Kong, using marine seismic reflection." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40722405.

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Zhang, Yaohui. "Common conversion point stacking for P-SV converted waves /." Access abstract and link to full text, 1992. http://0-wwwlib.umi.com.library.utulsa.edu/dissertations/fullcit/9218599.

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Laletsang, Kebabonye. "Seismic exploration for metallic mineral deposits /." Internet access available to MUN users only, 2001. http://collections.mun.ca/u?/theses,27435.

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Prada, Dacasa Manuel. "The structure and formation of the Tyrrhenian basin in the Western Mediterranean back-arc setting = Formación y estructura de la cuenca del Tirreno en el contexto de retrarco del Mediterráneo Occidental." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/245750.

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In this thesis I present a geophysical study that aims to define the structure and petrological nature of the main geological domains in the Central Tyrrhenian basin, and to investigate the mechanisms involved in their formation. The geophysical data used in this thesis was acquired during the MEDOC (2010) survey within the framework of the MEDOC project, which was designed to improve our understanding of the origin and evolution of rifted margins. The present work is based on the analysis, processing, modeling, and interpretation of coincident Wide-Angle Seismic (WAS), Multichannel Seismic (MCS), and gravity data corresponding to the two longest transects acquired during the MEDOC survey in the Central Tyrrhenian basin, the southern Line GH/MEDOC-6 (~450 km) and the northern Line EF/MEDOC-4 (~400 km). Both lines run across the Central Tyrrhenian basin from Sardinia to the Campania margin. The processing of MCS data provides the tectonic structure and geometry of the sedimentary basins, whereas the modeling of WAS data from travel-time tomography provides 2D seismic velocity models from which the velocity distribution of the crust and uppermost mantle, and the geometry of the crust-mantle boundary are inferred. The WAS models are then converted to density models using existing empirical relationships for different lithologies in order to test which of the different hypothesis concerning the petrological nature of the basement (e.g. continental/oceanic crust or exhumed mantle) explain better the observed gravity data. The results obtained together with the integration of geological data from rock sampling of the seabed reveals the existence of three geological domains in the Central Tyrrhenian, that is: continental crust, magmatic crust, and exhumed mantle. The comparison between the results of Line EF/MEDOC-4 (northern line) with those of the Line GH/MEDOC-6 (southern line) reveals that the velocity and tectonic structure of the three geological domains differ in some regions from north to south. These differences are most likely attributed to the southward increase of extension that characterizes the Tyrrhenian basin. The basement configuration presented in this thesis led to a completely new definition of geological domains in the Central Tyrrhenian. According to the presented distribution of the basement, rifting in the Central Tyrrhenian basin would have started with continental crust extension, continued with back-arc spreading leading to generation of magmatic back-arc crust, and followed by mantle exhumation intruded by later magmatic episodes. The interpretation of these results differ from current conceptual models of the formation of rifting systems involving mantle exhumation and indicate that the response of the continental lithosphere to extension processes may be more complex than previously assumed. Finally, to explain the mechanism involved in the formation of these domains, I examine the modes of back-arc basin formation proposed to explain the formation of the western Pacific basins [Martinez et al., 2007; Dunn and Martinez, 2011], as well as the causes that may have led to mantle exhumation [Pérez-Gussinyé, et al., 2006]. In summary, the proposed conceptual model is based on a slab rollback and depleted mantle setting, in which production of extension-related melting is limited, thus, crustal accretion is attributed to hydrous flux melting. The model presents 5 stages of opening that includes: (I) a normal subduction scenario followed by (II) development of the back-arc rift, (III) initiation of back-arc spreading, (IV) mantle exhumation, and finally (V) emplacement of large volcanic edifices in the central parts of the basin.
La tesis que presento se centra en el estudio de la estructura cortical y de los procesos de formación de la cuenca del Tirreno, con el principal propósito de ampliar el conocimiento sobre los mecanismos involucrados en la evolución de márgenes divergentes. Para ello, en esta tesis se realiza el procesado, análisis, modelización, e interpretación geológica de dos perfiles geofísicos adquiridos durante la campaña de sísmica marina MEDOC (2010) en el mar Tirreno. Ambos perfiles geofísicos incluyen datos de sísmica de gran ángulo (SGA), de reflexión multicanal (SRM) y de gravimetría, a partir de los cuales he obtenido los resultados siguientes: 1.Dos modelos de velocidad de propagación de ondas P (Vp) y de la geometría del Moho. 2.Análisis estadístico de incertidumbre de los parámetros de cada modelo de velocidad. 3.Modelado gravimétrico a partir de la conversión a densidad de los modelos de Vp. Con este método se pretende constreñir la petrología de los diferentes dominios geológicos a partir del empleo de diferentes relaciones empíricas de velocidad-densidad para diferentes tipos de roca. 4.Dos perfiles de SRM stackados y migrados en tiempo, de los cuales procesé uno de ellos (MEDOC 4). La interpretación conjunta de estos resultados junto con un análisis exhaustivo de las velocidades de los modelos, e información geológica de las rocas del lecho marino, han permitido caracterizar la naturaleza cortical (continental/oceánico) de los principales dominios geológicos en la cuenca del Tirreno central, los cuales incluyen: corteza continental, corteza de retroarco de carácter magmático y manto exhumado. Estos resultados junto con observaciones de la geomorfología de la batimetría, han dado paso a la discusión de la distribución en planta de dichos dominios geológicos en toda el área de estudio. Finalmente, propongo un modelo de apertura de cuenca en el cual se especula sobre la formación de los diferentes dominios geológicos identificados anteriormente. Dicho modelo se basa en los modos de apertura de cuencas de retroarco propuestos para las cuencas del Pacífico occidental, y en estudios de modelización numérica realizados para explicar la exhumación del manto en los márgenes pasivos del Atlantico Norte.

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Holguin, Macuster Ruben. "A SEISMIC REFLECTION STUDY OF A MISSISSIPPIAN MUD-MOUND NEAR ADEN, ILLINOIS." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2384.

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In 2011 and 2012 a Vibroseis™ seismic reflection survey, consisting of one westeast and one north-south seismic reflection profile, was conducted near the community of Aden (Hamilton County), Illinois, for hydrocarbon exploration purposes. Previous interpretations of the west-east seismic line (Ranaweera, 2015), as well as drill cuttings (Cantrell, 2011) from a nearby well (Webb #1), indicated the existence of a mud-mound within the Ullin Limestone. This thesis studied the shape and dimensions, as well as the seismic velocity properties, of the Aden mud-mound by re-processing and interpreting the Aden seismic reflection data. The interpretation process was aided by constructing two-dimensional synthetic seismograms from well log data from the nearby Broughton and Johnsonville oil fields, which are known locations of Waulsortian mud-mounds similar to the one inferred to exist at Aden. The results of this investigation indicate that the Aden mudmound has a longitudinal extent of approximately 0.6 miles (0.97 km) wide across the west-east ADEN #1 profile. From north-to-south on the ADEN #2 profile, the feature is approximately 0.7 miles (1.13 km) long. The geologic feature is located within the Ullin Limestone (Lower Mississippian) and is only manifested by the draping of younger strata overlying the mud-mound as observed on the seismic reflection images. Results from the 2D synthetic seismograms indicate that the seismic reflections generated across the known mud-mounds at Broughton and Johnsonville are similar to the seismic reflections seen at the location of the interpreted mud-mound on the Aden seismic reflection data. The presence of the Aden mud-mound is inferred by the draping of overlying strata above the mud-mound. This is interpreted to be caused by the increase in stratigraphic relief at the top of the Ullin, which becomes thicker at the mud-mound locations. Geologic and well log data from drill holes at Aden revealed that the interpreted Aden mud-mound formed in the Harrodsburg Member of the Ullin Limestone. The Harrodsburg is approximately 90 feet (27 meters) thick at Aden but becomes thicker at the location Webb #1 (up to 152 feet) where the mud-mound is located, indicating that the Aden mud-mound is at least 152 feet thick, when measured from the base of the Harrodsburg Member. A study of Root-Mean-Squared (RMS) and interval velocities, derived from sonic and pseudo-sonic log data from wells from the Aden, Broughton, and Johnsonville locations, indicated that RMS and interval velocities from the upper member (Harrodsburg Member) of the Ullin Limestone are higher than RMS and interval velocities present in the lower member (Ramp Creek Member) of the Ullin. Stacking velocities derived from the Aden seismic reflection data matched the RMS velocity values derived from sonic log data from drill holes at Aden with percent differences of less than 5%. This study indicates that stacking velocities at this location are accurate enough (within approximately 5%) to perform velocity studies when well log data from drill holes are not available. Additionally, there were no significant variations in stacking velocity profiles in the Ullin Limestone atthe Aden mud-mound location when compared to stacking velocity profiles derived at CMP locations away from the mud-mound. Likewise, there were no significant variations between RMS and Interval velocity profiles of the Ullin Limestone, derived from wells that were drilled into mud-mound locations at Aden, Broughton, and Johnsonville, and RMS and interval velocity profiles derived from wells that were drilled away from the mud-mound locations. The conclusion of this study is that RMS and interval velocity profiles, as well as stacking velocity profiles from seismic reflection data, are not good indicators for pinpointing the existence and location of carbonate mud-mounds. The best method to identify such carbonate structures is by interpreting their structure observed on seismic reflection records, including the draping effect on shallow reflections above the mudmound as observed in the recorded seismic reflection data, and by analyzing drill cuttings if available.

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Kahn, Daniel Scott. "The Blake Ridge a study of multichannel seismic reflection data /." Thesis, Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-06072004-131223/unrestricted/kahn%5Fdaniel%5Fs%5F200405%5Fms.pdf.

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39

Mustain, Mahmud. "The application of the shallow seismic reflection method and AVO analysis to identify the water table reflection." Thesis, University of Leicester, 2000. http://hdl.handle.net/2381/30442.

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A simple mathematical model of a sandstone aquifer has been constructed based on a local example, the Sherwood Sandstone of the East Midlands, UK. Simple seismic reflectivity calculations show that the air-water interface should theoretically produce a detectable seismic reflected wave for sandstone porosities as low as 10%. A synthetic seismic reflection dataset was constructed for a typical field survey geometry, and processed using the Promax system to produce a stacked section. The final section clearly shows the water table reflector. A field dataset from a subsequent survey has also been processed using the same sequence which also imaged a clear reflector at 30m depth. This is important evidence that the method has uses in identifying water table as a part of progress in shallow seismic reflection survey. The methods currently employed are (1) to define the optimum field, and (2) to define the optimum processing sequence, so that water table reflection can be imaged in a variety of geological situations. The application of Amplitude versus Offset (AVO) analysis to CMP gathers from the field data shows a characteristic increase of amplitude with increasing angle of incidence for super-critical reflection. In this way the water table reflector is clearly identified with the amplitude increasing by 30% over the range of incident angle from 28Â° to 34Â°. AVO analysis has also been applied to other field data that has a similar geological setting, but with a lithological reflector over the same super-critical angle. The resulting AVO curve shows a decrease in amplitude of over 90% with increasing offset, clearly differentiating from the water table reflection. Both water table and lithological results closely agree with theoretical predictions.

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Harsha, Senusi Mohamed. "Interpretation of Southern Georgia coastal plain velocity structure using refraction and wide-angle reflection methods." Thesis, Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/25886.

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Ahmadi, Omid. "Application of the Seismic Reflection Method in Mineral Exploration and Crustal Imaging : Contributions to Hardrock Seismic Imaging." Doctoral thesis, Uppsala universitet, Geofysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-259396.

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The seismic reflection method has been used extensively in mineral exploration and for imaging crustal structures within hardrock environments. In this research the seismic reflection method has been used and studied to address problems associated with hardrock settings. Papers I and II, address delineating and imaging a sulfide ore body and its surrounding rocks and structures in Garpenberg, central Sweden, at an active mine. 3D ray-tracing and finite-difference modeling were performed and the results suggest that although the detection of the ore body by the seismic reflection method is possible in the area, the presence of backfilled stopes in the mine makes seismic imaging of it difficult. In paper III the deeper structures of the Pärvie fault system in northern Sweden were revealed down to about 8 km through 2D seismic reflection profiling. The resulting images were interpreted using microearthquake data as a constraint. Based on the interpretation, some locations were suggested for future scientific deep drilling into the fault system. In paper IV, the seismic signature of complex geological structures of the Cue-Weld Range area in Western Australia was studied using a portion of a deep 2D seismic reflection profile. The pronounced reflections on the seismic images were correlated to their corresponding rock units on an available surface geological map of the study area. 3D constant velocity ray-tracing was performed to constrain the interpretation. Furthermore, the proposed structural model was tested using a 2D acoustic finite-difference seismic modeling method. Based on this study, a new 3D structural model was proposed for the subsurface of the area. These studies have investigated the capability of the seismic reflection method for imaging crustal structures within challenging hardrock and complex geological settings and show some its potential, but also its limitations.

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Demirbaäg, Mustafa Emin. "Estimation of seismic parameters from multifold reflection seismic data by generalized linear inversion of Zoeppritz equations." Diss., Virginia Tech, 1990. http://hdl.handle.net/10919/37224.

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Taikulakov, Yerlan Yengelsbekovich. "Subsurface Structure Of The Central Thrace Basin From 3d Seismic Reflection Data." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12612894/index.pdf.

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The Thrace Basin located in northwest Turkey displays attractive prospective traps for hydrocarbon and has received much attention from the petroleum industry. Despite the extensive exploration efforts, there are only few studies which address the fault kinematics and deformation mechanism of the region in connection with structural development. In this study, 3D raw seismic data set collected around Temrez High near Babaeski fault zone will be processed and interpreted along with the available borehole data to reveal the subsurface structure of the region that will contribute towards understanding the Neogene tectonic evolution of the central Thrace basin, origin of the transcurrent tectonics and possible role of the North Anatolian Fault Zone.

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Samson, Claire. "Recording the Kapuskasing pilot reflection survey with refraction instruments : a feasibility study." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66063.

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Janiszewski, Frank David. "Seismic reflection and gravity constraints on the bedrock configuration in the greater East Missoula area." CONNECT TO THIS TITLE ONLINE, 2007. http://etd.lib.umt.edu/theses/available/etd-05232007-120605/.

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Okojie-Ayoro, Anita Onohuome. "An approach to mapping of shallow petroleum reservoirs using sntegrated conventional 3D and shallow P- and SH-wave seismic reflection methods at Teapot Dome Field in Casper, Wyoming /." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2143.pdf.

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Hubbard, Susan S. "Paleozoic and Grenvillian structures in the southern Appalachians: extended interpretation from seismic reflection data." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/41998.

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Interpretive reprocessing of seismic reflection data and correlation of the seismic data with gravity data have elucidated Paleozoic and Grenvillian structures in the southern Appalachians. The seismic data include ADCOII, Seisdata, and COCORP reflection profiles which traverse the Blue Ridge and Inner Piedmont geologic provinces of South Carolina, North Carolina, and Georgia.

Based on the reprocessed data, all of the major faults within the allochthonous upper crust, including the Brevard fault zone and the Hayesville fault, are interpreted to root in the Blue Ridge master decollÃ©ment. Reflectors extending beneath the surface location of the Hayesville fault may be a deformational zone that extends in the direction of structural strike and is associated with Alleghanian transpression. Alternatively, the reflectors may actually represent the subsurface location of the J layesvil1e fault, in which case convergent reflector geometry of the Hayesvi1le fault and the Blue Ridge thrust suggest that the Blue Ridge thrust occupied a zone of weakness previously created by the Hayesville fault. Both the Blue Ridge thrust and Brevard fault zone ramps are interpreted to have a genetic re1ation to underlying basement topography. Relative amplitude data enabled the discrimination between Blue Ridge-Inner Piedmont crystalline rocks from underlying Lower Paleozoic shelf strata, thereby allowing the delineation of the Blue Ridge thrust. The revised geometry of the Blue Ridge thrust constrains the top of the shelf sequence beneath the Blue Ridge to depths less than 3 km. This relatively shallow depth of the shelf sequence, and the presence of duplex structures and bright spots within the sequence are auspicious factors for hydrocarbon exploration.

Reflectors within the upper-to-lower crust are interpreted to be preserved Grenvillian structures that were reactivated at the basement surface during Late Proterozoic-Early Cambrian extension. The reflectors are cross-cut by proposed post-Grenvillian, pre-Alleghanian low density intrusions that have acoustically transparent bases. Correlation of seismic and gravity data suggests that disturbances in the Douguer gravity field can be attributed to these structures within the autochthonous crust.

Discontinuous reflection packages from depths of 36-42 km are interpreted to originate from the Mohorovicic Discontinuity. The reflectors trend about N 15Â°E with a true dip of approximately 15Â°NW.
Master of Science

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Silva, Aristeguieta Maria. "Optimization of seismic least-squares inversion /." Access abstract and link to full text, 1993. http://0-wwwlib.umi.com.library.utulsa.edu/dissertations/fullcit/9325432.

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Jiao, Lingxiu. "Imaging of the Sudbury Structure, Ontario, Canada, using the seismic reflection and refraction method." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ62644.pdf.

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Ogilvie, Jeffrey Scott. "Modeling of seismic coda, with application to attenuation and scattering in southeastern Tennessee." Thesis, Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/25871.

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Dissertations / Theses on the topic 'Seismic reflection method. Geology'

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