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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

Detecting incised valley-fill sandstone in Beauchamp field by using seismic attributes, Stanton County, USA

Almalki, Saad Abdullah January 1900 (has links)
Master of Science / Department of Geology / Matthew W. Totten / A 3D seismic survey was conducted on Beauchamp, Beauchamp North and Beauchamp Northwest fields, which are located in Stanton County, southwest Kansas, by Berexco, Inc. Stanton County is situated on the Hugoton embayment which is the shelf of the Anadarko basin. The producing formation in this area is the Morrow formation, which is the lower Pennsylvanian period. The Morrow formation is mostly a clastic unit and its base was transgressive marine. It is considered an unconformity lying on the Mississippian rocks. Wide geologists agreed with the name of Morrow as name in the rock stratigraphic sequence in the study area (Forgotson, et al., 1966). "The Morrowan series is defined as the interval between the base of the Atokan Thirteen finger limestones and the top of the pre-Pennsylvanian unconformity" (Puckette, et al., 1996). The depositional environment of upper Morrow Formation in western Kansas, according to Sonnenberg (1985), Krystinik et al (1990), was a valley-fill deposit. The purpose of this study is to focus on detecting valley-fill sandstone in the study area by using appropriate seismic attributes. Coherence and discontinuity along dip succeeded to map incised valley-fill sandstone width. On another hand, spectral decomposition displayed subtle changes in incised valley thickness. Positive curvature shows valley edges in moderate resolution, but the most negative curvature wasn't clear enough to display the valley-fill sand. The result of RMS amplitude and average energy attributes results were almost the same. They exhibited four areas of high amplitude and energy in the valley which may indicate the presence of hydrocarbon. Sweetness and envelope amplitude both detected the valley in the study area. A gamma ray cross section shows that there are sequences of incised valley-fill sandstone which are sandstone A, B, C and D of the upper Morrow formation. Johns 2-12 well is producing oil from lower Morrow and sandstone A, thus the valley in the study area may produce oil from Sandstone A or B as RMS amplitude and average energy showing high amplitude in four areas in the valley.
2

Incorporating seismic attribute variation into the pre-well placement workflow, a case study from Ness County, Kansas, USA

Abbas, Mazin Y. January 1900 (has links)
Master of Science / Department of Geology / Matthew W. Totten / 3D seismic surveys have become the backbone of many exploration programs because of their high resolution and subsequent success for wildcat test wells. There are occasions when the predicted subsurface geology does not agree with the actual geology encountered in the drilled well. A case in point occurred during the drilling of several wells based upon a 3D seismic survey in Ness County, Kansas, where the predicted Cherokee Sand did not meet the expectations. By better understanding the subsurface geologic features in the subject area, this study will attempt to answer the question “what went wrong?” Seismic attribute analysis workflow was carried out and the results were correlated to the available geological and borehole data within the survey boundaries. The objective of running this workflow was to describe facies variations within the Cherokee Sandstone. Correlations between seismic attributes and physical properties from well data were used to define these variations. Finally, Distributions of the seismic facies were mapped to predict the distribution of potential reservoir rocks within the prospect area.
3

ANALYSIS OF THICKNESS VARIATIONS OF THE AUX VASES FORMATION IN WHITE COUNTY, ILLINOIS THROUGH APPLICATION OF GEOPHYSICAL WELL LOGS AND 3-D SEISMIC REFLECTION ATTRIBUTES

Smith Jr, Richard Lee 01 August 2015 (has links)
A two square mile (5.2 square kilometer) 3-D seismic reflection survey was completed in northeastern White County, Illinois for petroleum exploration in January of 2008. Well log data was made available from Royal Drilling and Producing, who contracted the seismic survey, and additional data was retrieved from the ILOIL database. Raster (TIFF format) images that were available for nearly every well location in the study area were calibrated for depth and stratigraphic tops picked. The purpose of this study is to analyze the Aux Vases formation using 3-D seismic reflection data and attribute analysis by comparing this data to well log information that is greatly available in the study area. Synthetic seismograms were calculated to calibrate seismic reflection data time to actual geological depth to a formation. The synthetic seismograms were calculated using wavelets extracted from the 3-D seismic data and edited, digital (LAS format) sonic and density logs measured in three wells. Geophysical log data from wells in the area were used to interpret formation top and bottoms. With the Aux Vases and Ste. Genevieve top information, an isopach was generated. Horizons were handpicked in all 318 seismic lines and isochron maps were generated to compare time thickness to actual thickness of the isopach maps. Attribute analysis was performed on horizon and volume cubes to interpret the Aux Vases formation in the study area. These attributes included instantaneous phase, instantaneous amplitude, and instantaneous frequency. Additionally, multiple spectral decomposition cubes (from four SEG-Y volumes) were generated for 520-580 ms intervals and interpreted at 550 ms. The combination of this data lead to identification of two larger stratigraphic bodies and several smaller ones in the study area. Thickness comparison between these attributes and isopach maps was completed and found similarities that can be used to determine potential thickness. A thickness estimate was completed at Well B using the frequency from spectral decomposition. A channel was mapped in the western edge of the survey using spectral decomposition and other attributes. Finally, a fault was identified in the southeastern portion of the survey area.
4

3D seismic attributes analysis in reservoir characterization: the Morrison NE field & Morrison field, Clark County Kansas

Vohs, Andrew B. January 1900 (has links)
Master of Science / Department of Geology / Abdelmoneam Raef / Seismic reservoir characterization and prospect evaluation based 3D seismic attributes analysis in Kansas has been successful in contributing to the tasks of building static and dynamic reservoir models and in identifying commercial hydrocarbon prospects. In some areas, reservoir heterogeneities introduce challenges, resulting in some wells with poor economics. Analysis of seismic attributes gives insight into hydrocarbon presence, fluid movement (in time lapse mode), porosity, and other factors used in evaluating reservoir potential. This study evaluates a producing lease using seismic attributes analysis of an area covered by a 2010 3D seismic survey in the Morrison Northeast field and Morrison field of Clark County, KS. The target horizon is the Viola Limestone, which continues to produce from seven of twelve wells completed within the survey area. In order to understand reservoir heterogeneities, hydrocarbon entrapment settings and the implications for future development plans, a seismic attributes extraction and analysis, guided with geophysical well-logs, was conducted with emphasis on instantaneous attributes and amplitude anomalies. Investigations into tuning effects were conducted in light of amplitude anomalies to gain insight into what seismic results led to the completion of the twelve wells in the area drilled based on the seismic survey results. Further analysis was conducted to determine if the unsuccessful wells completed could have been avoided. Finally the study attempts to present a set of 3D seismic attributes associated with the successful wells, which will assist in placing new wells in other locations within the two fields, as well as promote a consistent understanding of entrapment controls in this field.
5

[en] SEISMIC AMPLITUDE SMOOTHING BY ANISOTROPIC DIFFUSION PRESERVING STRUCTURAL FEATURES / [pt] SUAVIZAÇÃO DE DADOS DE AMPLITUDE ATRAVÉS DE DIFUSÃO ANISOTRÓPICA COM PRESERVAÇÃO DE FEIÇÕES SÍSMICAS

PATRICIA CORDEIRO PEREIRA PAMPANELLI 23 February 2016 (has links)
[pt] A interpretação sísmica consiste em um conjunto de metodologias que visam compreender o modelo estrutural e estratigráfico de uma determinada região. Durante este processo, o intérprete analisa a imagem sísmica buscando identificar estruturas geológicas como falhas, horizontes e canais, dentre outras. Dada a baixa razão sinal-ruído, os algoritmos que dão suporte à interpretação precisam de uma etapa de pré-processamento onde o ruído é reduzido. Esta tese propõe um novo método de filtragem por difusão anisotrópica que melhor preserva as feições sísmicas de interesse. A formulação do processo de difusão permite que os atributos identificadores de horizontes e de falhas sejam incorporados ao método a fim de evitar que estas estruturas sejam corrompidas durante a difusão da amplitude sísmica. O método proposto implementado apresenta resultados aplicados a dados reais disponíveis na literatura. Para estes resultados, é apresentada uma análise da influência do método de filtragem anisotrópica proposta nas medidas de correlação ao longo de horizontes previamente rastreados. Finalmente, a tese apresenta algumas conclusões e sugestões para trabalhos futuros. / [en] Seismic interpretation can be viewed as a set of methodologies to enhance the understanding of the structural and stratigraphic model of a given region. During this process, the interpreter analyzes the seismic imaging seeking to identify geological structures such as faults, horizons and channels, among others. Given the low signal to noise ratio, the algorithms that support the interpretation require a pre-processing stage where the noise is reduced. This thesis proposes a new filtering method based on the anisotropic diffusion of the amplitude field. The formulation of the diffusion process proposed here uses seismic attributes to identify horizons and faults that are preserved in the diffusion process. The proposed method implemented in this thesis also presents results applied to real and synthetic data. Based on these results, we present an analysis of the influence of the proposed method in correlation measurements over horizons previously tracked. Finally the thesis presents some conclusions and suggestions for future work.
6

[en] CLASSIFICATION OF SEISMIC FACIES USING SEISMIC MULTI-ATTRIBUTE / [pt] CLASSIFICAÇÃO DE FÁCIES SÍSMICAS UTILIZANDO MULTIATRIBUTOS SÍSMICOS

NELIA CANTANHEDE REIS 20 October 2022 (has links)
[pt] A interpretação sísmica é um processo fundamental para a exploração de hidrocarbonetos. Essa atividade consiste na identificação de informação geológica através do processamento e análise de dados sísmicos. Com o crescimento acentuado e a complexidade dos dados sísmicos, a análise manual de fácies sísmicas tornou-se um desafio significativo. O mapeamento de fácies sísmicas é um processo demorado e que requer profissionais especializados. O objetivo deste trabalho visa aplicar a classificação multiatributos usando uma rede neural encoder-decoder para mapear as fácies sísmicas e auxiliar no processo de interpretação. Um conjunto de atributos sísmicos, foram calculados utilizando o software Opendtect versão 6.6 a partir dos dados de amplitude contidos no Dataset Facies-Mark . Sendo eles: Energia, Pseudo Relevo, Fase instantânea e Textura, todos foram selecionados por um intérprete. A função de perda utilizada pela rede foi weighted categorical crossentropy, pelo fato das classes serem consideravelmente desbalanceadas. O treinamento foi realizado nas direções inlines e crosslines para as respectivas combinações: atributos, atributo + amplitude, e somente a amplitude. Os resultados baseado na métrica frequency weighted intersection over union (FWIU), mostraram que os atributos junto com a amplitude obtiveram o melhor resultado, 85,73 por cento, em comparação com as outras combinações citadas. Em comparação direta com o trabalho que inspirou essa dissertação, o multiatributos performou melhor. / [en] Seismic interpretation is a fundamental process for hydrocarbon exploration. This activity consists of identifying geological information through the processing and analysis of seismic data. With seismic data s rapid growth and complexity, manual seismic facies analysis has become a significant challenge. Mapping seismic facies is a time-consuming process that requires specialized professionals. The objective of this work is to apply multi-attribute classification using an encoder-decoder neural network to map the seismic facies and assist in the interpretation process. A set of seismic attributes were calculated using Opendtect version 6.6 software from the amplitude data contained in the Facies-Mark Dataset. These being: Energy, Pseudo Relief, Instant Phase, and Texture were all selected by an interpreter. The loss function used by the network was weighted categorical cross-entropy, because the classes are considerably unbalanced. The training was performed in the inlines and crosslines directions for the respective combinations: attributes, attribute + amplitude, and only the amplitude. The results based on the frequency weighted intersection over union (FWIU) metric showed that the attributes along with the amplitude obtained the best result, 85.73 percent, compared to the other combinations mentioned. In direct comparison with the work that inspired this dissertation, multi-attribute performed better.
7

Submarine mass movement processes on the North Sea Fan as interpreted from the 3D seismic data

Gafeira Gonçalves, Joana January 2010 (has links)
This research has been focused on the characterisation and analysis of the deposits of large-scale mass movement events that shaped the North Sea Fan since the Mid-Pleistocene. Located at the mouth of the cross-shelf trough Norwegian Channel, the North Sea Fan is one of the largest through-mouth fans in the glaciated european margin with an area of approximately 142,000 km2. Submarine mass movement processed have occurred intermittenrly throughout the Quarternary history of the North Sea Fan, related to recurrent climate-related episodes of growth and retreat of the ice sheets. These processes can transport large amounts of sediment from the upper shelf up to the abyssal basins, playing an important role on the evolution of continental margins and can also reporesnet major geological hazards. This thesis uses mainly 3D seismic data to investigate the external geometry and internal structure of large-scale mass movement deposits. The high spatial resolution provided by the 3D seismic data has allowed a detailed geomorpholocial analysis of these deposits, This study involved the interpretation of the seismic data and the detailed pickling of key reflectors followed by tge extraction of both horizon and window-based seismic attributes. Digital elevation models of the key reflectors and their seismic attribute maps were then transferred to a geographical information system (GIS) where they were interactively interpreted using spatial analysis tools and the full visualisation potential of the software. The outcomes of this study highlight the importance of detailed horizon pickling and interactice interpretation followed by spatial analysis and visualisation in GIS environment. The identification of acoustic patterns within deposits that are normally described from 2D seismic as chaotic or acoustically transparent emphasizes the potential of detailed analysis of 3D seismic data. It gives an example of how this type of data can provide new insights into the mechanisms and processes associated with mass movements. In particular, amplitude and RMS amplitude maps provide remarkable detailed information of internal deformation structures whereas slope, shaded-relief and thickness maps allowed detailed characterisation of the external geometry. Various types of kinematic indicators can be recognized within the mass movement deposits through combined seismic analysis and detaield morphological mapping.
8

Komplexní seismické atributy a jejich aplikace na data z Mistlbašské kry / Complex seismic attributes and their application to Mistelbach block

Voroňáková, Jana January 2014 (has links)
The purpose of this diploma thesis is to apply complex seismic attributes on 3D seismic data from Mistelbach block area and trying to figure out whether they are useful by seismic interpretation process. The geology of Vienna basin and the characteristics of Complex seismic attributes will be discussed. The thesis also includes analysis of the Lednice 11 gas reservoir and a new potential hydrocarbon reservoir identification, both using complex seismic attributes.
9

Accélération matérielle pour l’imagerie sismique : modélisation, migration et interprétation / Hardware acceleration for seismic imaging : modeling, migration and interpretation

Abdelkhalek, Rached 20 December 2013 (has links)
La donnée sismique depuis sa conception (modélisation d’acquisitions sismiques), dans sa phase de traitement (prétraitement et migration) et jusqu’à son exploitation pour en extraire les informations géologiques pertinentes nécessaires à l’identification et l’exploitation optimale des réservoirs d’hydrocarbures (interprétation), génère un volume important de calculs. Nous montrons dans ce travail de thèse qu’à chacune de ces étapes l’utilisation de technologies accélératrices de type GPGPU permet de réduire radicalement les temps de calcul tout en restant dans une enveloppe de consommation électrique raisonnable. Nous présentons et analysons les éléments sous-jacents à ces performances. L’importance de l’utilisation de motifs d’accès mémoire adéquats est particulièrement mise en exergue étant donné que l’accès à la mémoire représente le principal goulot d’étranglement pour les algorithmes abordés. Nous reportons des facteurs d’accélération de l’ordre de 40 pour la modélisation sismique par résolution de l’équation d’onde par différences finies (brique de base pour la modélisation et l’imagerie sismique) et entre 8 et 113 pour le calcul d’attributs sismiques. Nous démontrons que l’utilisation d’accélérateurs matériels élargit considérablement le champ du possible, aussi bien en imagerie sismique (modélisation de nouveaux types d’acquisitions à grande échelle) qu’en interprétation (calcul d’attributs complexes sur station de travail, paramétrage interactif des calculs, etc.). / During the seismic imaging workflow, from seismic modeling to interpretation, processingseismic data requires a massive amount of computation. We show in this work that, at eachstage of this workflow, hardware accelerators such as GPUs may help reducing the time requiredto process seismic data while staying at reasonable energy consumption levels.In this work, the key programming considerations needed to achieve good performance are describedand discussed. The importance of adapted in-memory data access patterns is particularlyemphasised since data access is the main bottleneck for the considered algorithms. When usingGPUs, speedup ratios of 40× are achieved for FDTD seismic modeling, and 8× up to 113× forseismic attribute computation compared to CPUs.
10

Rock formation characterization for carbon dioxide geosequestration: 3D seismic amplitude and coherency anomalies, and seismic petrophysical facies classification, Wellington and Anson-Bates fields, Sumner County, Kansas, USA

Ohl, Derek Robert January 1900 (has links)
Master of Science / Department of Geology / Abdelmoneam Raef / Amid increasing interest in geological sequestration of carbon dioxide (CO2), detailed rock formation characterization has emerged as priority to ensure successful sequestration. Utilizing recent advances in the field of 3D seismic attributes analysis, offers improved opportunities to provide more details when characterizing reservoir formations. In this study, several post-stack seismic attributes integrated with seismic modeling for highlighting critical structural elements and petrophysical facies variation of rock formations at Wellington and Anson-Bates fields, Sumner County, Kansas. A newly acquired 3D Seismic data set and several geophysical well logs are also used to achieve the objectives of this study. Results sought in this study are potentially important for understanding pathways for CO2 to migrate along. Seismic amplitude, coherency, and most negative curvature attributes were used to characterize the subsurface for structural effects on the rock formations of interest. These attributes detect multiple anomaly features that can be interpreted as small throw faults. However, in this study, there is a larger anomalous feature associated with the Mississippian formation that can be interpreted as a small throw fault or incised channel sand. Determining which of the two is very important for flow simulation models to be more exact. Modeling of the seismic was undertaken to help in the interpretation of the Mississippian amplitude anomaly. An artificial neural network, based on well log porosity cross-plots and three seismic attributes, was trained and implemented to yield a seismic petrophysical facies map. The neural network was trained using three volume seismic waveform attributes along with three wells with difference in well log porosity. A reworked lithofacies along small throw faults has been revealed based on comparing the seismic structural attributes and the seismic petrophysical facies. Arbuckle formation characterization was successful to a certain degree. Structural attributes showed multiple faults in the northern half of the survey. These faults are in agreement with known structure in the area associated with the Nemaha uplift. Further characterization of the Arbuckle was hindered by the lack of well data. This study emphasizes the need for greater attention to small-scale features when embarking upon characterization of a reservoir for CO2 based geosequestration.

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