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4th International Congress of the Brazilian Geophysical Society
- Conference date: 20 Aug 1995 - 24 Aug 1995
- Location: Rio de Janero, Brazil
- Published: 20 August 1995
301 - 330 of 330 results
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The Newmont VLFIMagnetometer System
Authors B. Nilsson and E. LauritsenNewmont Exploration developed a combined VLFlMagnetometer system in 1989, permitting simultaneous measurements ofVLF resistivity and the earth's magnetic field. The Magnetometer utilizes an Overhauser sensor, developed by GEM Systems, while the VLF receiver was developed in-house. The receiver has a frequency range of 10 to 30 kHz, allowing for the use of the Global OMEGA Navigation System which operates continuously in the 10 to 14 kHz frequency range. The receiver uses a short electric antenna, allowing for one-man operation.
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Stable Numerical Wavefield Transforms of TEM Data
Authors E. C. Slob, T.M. Habashy and C. Torres-VerdinSuccessful application of the wavefield transform to diffusive electromagnetic (TEM) field data opens up the possibilities of processing the data with the well known seismic processing techniques. Since the time source functions used in field surveys are usually step-current switches, the fields in the wavefield transform domain will be the response to a linear function, which is the q-domain equivalent source. Hence, the fields will in general be unbounded for large values of q and have delta-like and step-like is continuities for those values of q that correspond to the arrivals of waves. It is exactly this correspondence principle that makes a numerical implementation of the transform very difficult. This consideration has recently led to a reformulation of the wavefield transformation, where the q-domain field is convolved with a window function that is a smooth function of q which has zero mean. The window function can be chosen freely as long as it has a zero mean. The convolved fields will then be smooth and vanish for large values of q. Hence, TEM data should be convolved with the time domain equivalent of the window function and then be transformed to the qdomain. Since we have control over the window function, we have a controlled convolution problem in the q-dornain to find arrival times. Two numerical methods have been successfully tested, using the convolution, for single arrival data. Now we test it on more general TEM data.
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Detecting Trap Leakage with ALF, the Airborne Laser Fluorosensor; Contrasting Results from Contrasting Basin Settings
By A. WilliamsThe majority of the world's onshore oil fields leak very small quantities of petroleum to the earth's surface as seepage (Clarke and Cleverly, 1991). In new basins such seeps mark the ends of migration pathways and indicate the presence of undiscovered oil and gas accumulations. In many offshore petroliferous basins, the seeped oil forms such thin films that they are invisible to the naked eye or to other airborne or satellite-mounted detectors. ALF, the Airborne Laser Fluorosensor, however, can detect oil films down to a thickness of 0.005 microns and also provides information on hydrocarbon phase. ALF has detected such low levels of seepage -microseepage - in three contrasting basin settings; - • the Gulf of Mexico Slope, a structured (diapiric) passive margin where normal gravity oils and condensates are the dominant hydrocarbon phase • the Dampier Basin, Northwest Shelf of Australia, a relatively unstructured passive margin where light oils and condensates are typical • the Faeroes Basin, West of Shetlands, a Tertiary passive margin overlying a failed Mesozoic rift where both heavy oils and condensates are trapped. In each case, ALF results are contributing important new information on the limits of the playfairways and the phase of the trapped hydrocarbons.
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Aplicaçăo do Método "Analytic Signal" no Mapeamento das Soleiras de Diabásio da Regiăo.de Fartura (SP-PR)
O presente trabalho mostra a aplicaçăo do método Analytic Signal (Nabighian 1972; Macleod et al. 1993) a dados aeromagnéticos residuais de uma área do Projeto Aerogeofísico Botucatu (Paulipetrc-Encal 1972), limitada pelas seguintes coordenadas geográficas: 49°00' a 50°00' de longitude oeste e. 23°00' a 24°00' de latitude suI. As linhas de vôo foram posicionadas na direçăo N-S, espaçadas de 2000m, e os dados foram tornados a uma altura media de 450m sobre o terreno. Também foram realizados 4 (quatro) perfis magnetométricos terrestres, totalizando cerca de 16km, cujas principais anomalias foram modeladas visando definir as características magnéticas e a geometria dos corpos causadores.
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Justificativas Para Urn Levantamento Aerogravimétrico na Bacia dos Parecis, Mato Grosso (Brasil)
By F. MarinhoOs trabalhos de pesquisa para a definiçăo da arquitetura geológico-estrutural da Bacia dos Parecis, embasando uma avaliaçăo consistente do seu potencial petrolifero, tęm sido dificultados pela presença de florestas muito densas áreas inacessíveis (reservas indigenas, fazendas de acesso proibido, etc.), extensa rede drenagem e pobre rede viária. Os dados aeromagnéticos da porçăo oeste da bacía propiciaram interpretaçőes conflitantes relativas ŕ estruturaeao e espessura sedimentar. Todavia, o levantamento de 478 km de linhas sismicas de reconhecimento e 0 levantarnento gravimétrico regional (Petrobras, 1992, 1993), permitiram a definiçăo do arcabouço estrutural da bacia e a possível continuaçăo para leste das suas principais feiçőes estruturais. A interpretaçăo conjunta das seçőes sísmicas de reconhecimento (Siqueira e Teixeira, 1993) e dos dados de campos potenciais, apoiada por modelagens de dados gravimétricos e magnetométricos (Braga e Oliveira, 1994), deram suporte ŕ proposiçăo de tres perfuraçőes estratigráficas. A eficácia do método gravimétrico na definiçăo da estruturaçăo do embasamento da parte oeste desta bacia e as dificuldades naturais em estendę-lo para leste por via terrestre, justificam a realizaçăo dos aerolevantamentos combinados de gravimetria e magnetometria na porçăo oriental da bacia. Este é o primeiro levantamento aerogravimétrico no Brasil e seus resultados preliminares serăo apresentados no congresso.
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Analise Critica do Nivelamento de Dados Geofisicos com Ajustes dos Erros de Cruzamento em Levantamentos Maritimos
Authors J.P. Rebés Lima and M. Polo Pereira da Boa HoraOs Erros de Cruzamento (''Cross-Over Erros" - COEs) săo discrepâncias observadas nos valores de parâmetres geofisicos obtidos nos pontos de interseçăo de linhas de rotas de cruzeiros em levantamentos marítimos. Existem diversos fatores que contribuem para a existęncia destes erros, sendo que uma porçăo substancial dos mesmos tem origem sistemática e pode ser reduzida por análise dos COEs para cada cruzeiro.
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Base de Dados de Projetos Aerogeofisicos do Brasil (Aero)
More LessA Companhia de Pesquisa de Recursos Minerais (CPRM), o Serviço Geológico do Brasil, empresa pública subordinada ao Ministério de Minas e Energia, elaborou, a partir de 1986, o Sistema de lnformaçőes Geológicas do Brasil (SIGA), o qual consiste em um conjunto de bases de dados de geocięncias com vistas a apoiar o Programa Levantamentos Geológicos Basicos do Brasil (PLGB), convęnio inicialmente celebrado entre o Departamento Nacional da Produçăo Mineral (DNPM) e a CPRM. Considerando o grande acervo de dados digitais e cartográficos de projetos aerogeofisicos conduzidos pela CPRM (levantamento, processamento e interpretaçăo), bem como por ser ela que mantem o controle de qualidade e a guarda, desde a década de 1970, dos projetos aerogeofisicos patrocinados por órgăos governamentais e algumas empresas privadas de mineraçăo, e tendo em vista as inúmeras solicitaçőes do público interessado nesses dados como suporte ŕ cartografia geológica e em projetos de prospecçăo e pesquisa minerais, a CPRM houve por bem elaborar também um modele de base de dados aerogeofisicos que viesse contemplar o usuário com as principais informaçőes técnicas de caráter documental, possibilitando a consulta on line via terminal de computador ou através de microcomputador (disquete ou CD-ROM): a Base de Dados de Projetos Aerogeofisicos do Brasil (AERO) disponivel ao público, na sua primeira etapa, a partir de 1992.
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Determinaçăo de Superficie Curie: Regiăo Central de Goiás
Authors M. de Lawrence B. Blum and A.C. Bittencourt PiresA distribuçăo de temperatura e pressăo na litosfera terrestre afeta uma grande variedade de propriedades e processos fisicos. As propriedades magnéticas das rochas săo afetadas de tal modo que, em algum lugar do interior da Iitosfera, a temperatura chega a um ponto em que a magnetizaçăo é perdida. É possível estimar a profundidade desse ponto através do tratamento de dados magnéticos com base em certas suposiçőes.
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Multi-Diciplinary Integration Utilizing Visualization Technology: A Case Study
Authors A. A. Peloso and A. DeweyRecent advances in visualization technology have provided a means to reduce uncertainty in hydrocarbon recovery. Integrating, geophysical, geological, and geostatistical data in a common three-dimensional scene provides the basis for making better informed decisions towards characterizing the reservoir. To illustrate this approach, this paper presents at from the South Casper Creek Field in Wyoming. The Casper Creek Field is a foreland fold of the Rocky Mountains. The focus of this study is the producing oil reservoir Tensleep sand of Pennsylvanian age. The Tensleep lies above the marine evaporite Amsden formation and below the evaporites, carbonates and silts of the Phosphoria formation (Agatson,1952).
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Superficie Curie e Relaçőes com Geologia, Geofísica e Recursos Minerais da Regiăo Central de Goiás
Authors M. de Lawrence B. Blum and A.C. Bittencourt PiresA regiăo central de Goiás, principalmente a situada entre os paralelos 14° e 16°S e os meridianos 48° e 51°W (área de estudo), tem despertado a curiosidade de muitos desde o século XVIII, quando as bandeiras se embrenharam pelo sertăo goiano em busca de ouro. Todavia, o interesse năo é só econômico. Sua complexidade geológica (Figura 1) tem atraído diversos pesquisadores nas últimas décades na tentativa explicar sua gęnese.
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Interpretaçăo de Imagem Magnética Digital: Regiăo Central de Goiás
Authors M. de Lawrence B. Blum and A.C. Bittencourt PiresO uso de imagens geofisicas digitais em interpretaçőes diversas, ou mesmo em conjunto com outras informaçőes, tem se tornado, a cada dia, indiscutivelmente importante. Isso se deve ŕ alta qualidade e facilidade de visualizaçăo que a maioria das imagens proporciona. Qualidade e facilidade estas dificeis de se encontrar em mapas de contorno muito detalhados. Filtros de freqüęncia tambem tęm sido muito utilizados em dados geofisicos. Esses filtros servem para realçar ou revelar anomalias de interesse geológico-prospectivo. Neste estudo, dados aeromagnéticos do Projeto Geofisico Brasil-Canadá da regiăo central de Goiás săo interpretados utilizando-se imagem geofisica e filtro de freqüęncia 'passa-baixa'.
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Desempenho de Métodos de Interpolaçăo Espacial na Composiçăo de Mapas Aerogeofísicos.
Authors R. Stevanato, F.J. Fonseca Ferreira, P.C. Soares and F. Valdyr da SilvaNeste trabalho săo comparados diversos métodos de interpolaçăo ou inferęncia de dados aerogeofisicos como o bidirecional, a curvatura mínima e a geoestatistica.
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Gravimetria da Suite Intrusiva de Itú-SP
Authors T. Mtanos Mouallen, W. Shukowsky and M.S. Maria MantovaniA regiăo de ltú, delimitada pelos paralelos 22.8°S e 23.5°S e pelos meridianos 46.7OW e 47.6"W, situa-se na zona de transiçăo entre os terrenos Pré-cambrianos e as coberturas sedimentares da Bacia do Paraná no Estado de Săo Paulo (Figura 1). Acompanhando a porçăo leste da borda da bacia, ao norte da Falha de Extrema observa-se o Complexo Amparo, composto principalmente de gnaisses, migmatitos, quartzitos existos do Proterozóico Inferior. Intrudidos nesses terrenos, granitóides sin- e tardi-orogęnicos do Ciclo Brasiliano, se extendem por uma área de aproximadamente 400 km, constituindo a Suite intrusiva de ltu (Pascholati, 1987). Ao sul da Falha de Extrema situam-se os metassedimentos do Grupo Săo Roque, constituídos por filitos, xistos e quartzitos do Proterozóico Superior.
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Mapa de Anomalias Bouguer no Estudo do Arcabouço Tectónico do Sul de Minas Gerais: Dados Preliminares
Authors W. Malagutti Filho, Y. Hasui, N. Haraly, H.D. Ebert, P.C. Hackspacher and J. R. SturaroNo presente trabalho săo apresentados os resultados de um levantamento gravimétrico executado por pesquisadores do IGCE - UNESP, na regiăo sul do Estado de Minas Gerais.O objetivo principal da pesquisa é a contribuiçăo para o conhecimento do arcabouco tectônico da regiăo com enfase ŕ delineaçăo das suturas que definem as articulaçőes entre os blocos Săo Paulo, Brasilia e Vitória. As estaçőes gravimétricas foram levantadas com um gravímetro Lacoste-Romberg e os valores de altitude foram obtidos a partir de um levantamento barométrico. As figuras mostradas no final do trabalho ilustram a distribuiçăo dos pontos e o mapa de Anomalias Bouguer obtido, no qual podem ser observadas algumas das principais feiçőes geotectônicas da área.
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Paleomagnetism of Carbonatic Sedimentary Sequences of the Salitre Formation - Chapada Diamantina - Bahia
More LessPreliminary paleomagnetic results for 25 oriented hand samples and 71 oriented cylindrical cores of carbonates from the Salitre Formation (Sao Francisco Craton) are presented. The carbonate deposition is considered to have occurred probably between 767Ma and 900Ma. Most samples yielded a northern direction with high positive inclination after alternating field and thermal treatments. The calculated mean magnetization direction was Dm=3.7°; Im=67.1° (
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Gravimetric Mapping of theTaubate Basin Structural Framework, Southeast Brazil
Authors F.L. Fernandes and C.H. KiangA gravimetric survey was executed on the Taubate Basin in order to know its basement geometry. A LaCoste&Romberg gravimeter was used to acquire 646 sites, in an area of 3000 J(m2 on the Taubate Basin and proximaJ basement. Two filters were applied on the original data to maximize the signal of the basin. The filtered map was calibrated with the interpretation of PETROBRAS seismic section to generate a structural map of the basement. According to the shape and geometry of the compartments, Taubate Basin can be interpreted as a typical example of RIFT basin.
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Magnetic Anomalies on the Argentine Continental Shelf
Authors M. E. Ghidella, C. M. Paterlini, L. C. Kovacs and G. A. RodriguezARGUS is a joint program between NRL (Naval Research Laboratory. U.S. Navy) and SIHN (Servicio de Hidrograffa Naval, Argentine Navy), whose objective is to carry out a detailed survey of the Argentine continental shelf. The first stage of this project was erformed in April, 1991, and covered the area between 35° S and 45° . S. The second stage took place in September, 1993, and extended the coverage to 47° S. The aircraft used was a long range Orion P-3, belonging to the US Navy and equipped by NRL. The data set complements formerly existing marine data, providing a denser coverage over the shallow water zones, which comprise the continuation of important continental sedimentary basins as well as features related to the Atlantic Ocean rifting processes. In this paper we present magnetic anomaly maps together with a preliminary interpretation, based upon the maps themselves and formerly existing Geophysical data.
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Interpretacion Geofisica Integrada de un Transecto NW-SE a través de Los Andes Venezolanos
Authors l. A. Escobar and I. RodriguezEn base a datos gravimétricos y aeromagnéticos se propone un modelo cortical de un transecto a través de los Andes Venezolanos, considerando: los mecanismos focales determinados por Pennington (1980) para el NW de Sur America, las evidencias paleomagnéticas de rotación del bloque andino asociada a un sistema de cizallas dextrales (Pindell y Barrett, 1990) y la presencia de una superficie de despegue a nivel de basamento bajo el sistema de semigrabens reactivados en forma inversa durante el Neógene, que conforman el cinturón plegado que define los Andes Venezolanos (Alezones et al., 1994). Se retoma la idea de corteza flexionada "raíz litosférica" bajo el minimo gravimétrico en la antefosa del Lago de Maracaibo, descartando la presencia de subducción tipo A por falta de evidencias sismo- lógicas, estadisticamente aceptables. El modelo propone rotación y desplazamiento de las estructuras asimétricas que conforman los Andes venezolanos hasta adoptar su configuración actual, dejando atrás la corteza flexionada y generando un desbalance isostático local.
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A 2-D Resistivity Survey on the Investigation of the Low Enthalpy Geothermal Field of Kimolos Island, Greece
Authors I.F. Louis, P. Tsourlos and V. KarastathisIn this study we present the results of a 2-D electrical resistivity survey carried out on Kimolos Island (Greece) aiming to investigate the shallow conductivity structure of the north eastern part of the Island and therefore to assist In the evaluation of its geothermal potential. The collinear dipole-dipole resistivity technique was used in the field for the data set acquisition. The analysis of these observations determined the vertical and lateral extent of the electrical resistivity variation and allowed the detailed delineation of a E-SW trending tectonic structure, which Is the main carrier of the low enthalpy geothermal fluid. The results presented by means of cross sections are well correlated with drilling results, hot springs and other surface manifestations of the geothermal activity.
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DEFORMATION HISTORY OF THE SIERRA MADRE ORIENTAL, MEXICO, AND ASSOCIATED HYDROCARBON System
Authors G. Prost, R. Marrett, M. Aranda, S. Egulluz, J. G. Galicia, J. Banda, J. Patino and S. OnuńoAn examination of the tectonic development and deformation style of the Sierra Madre Oriental (SMO) was undertaken as the first part of a joint project involving Pemex, the Instituto Mexicano del Petr61eo, and Amoco. This served as a starting point for an evaluation of the petroleum potential of this folded thrust belt. Structural style and amount of shortening along this Laramide thrust belt was found to be a function of the type of decollement: detachment in a weak (evaporite) layer tends to generate box or "fan" folds and few emergent thrusts, whereas detachment in . stronger units (shales, limestones) is associated with fault-bend and fault-propagation folds and emergent thrusts. All of these folds have been, for the most part, deeply eroded and reservoir units tend to be breached. Thermal maturity is also high (dry gas) over most of the SMO, and modeling suggests that in much of the area hydrocarbons were generated and migrated before Laramide deformation.
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Migración en profundidad 2D preapilamiento con la ecuación de onda transforamada linealmente
By V. CelisEn este trabajo se presenta la extensión a migración en profundidad de la metodología basada en la ecuación de la onda bajo una transformación lineal en su versión de preapilamiento 2D. Perfiles migrados son obtenidos del proceso y los mismos son sumados por receptor común para obtener la sección cero "offset" migrada preapilamiento. El método no tiene restricciones en cuanto al ángulo de buzamiento de las reflexiones y es capaz de manejar fuertes variaciones laterales de velocidad. El algoritmo es probado con datos sintéticos y reales.
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Evaluación de Algoritmos de Migración en Tiempo y Profundidad, Pre-apilamiento y Post-amilamiento
Authors C.E. Moreno, E. Del Pino, H. Cerquone and E. RoaCon datos sintéticos generados a partir de un modelo que simula rasgos de una zona estructuralmente compleja, se evaluan distintos algoritmos de migración, en tiempo y profundidad, post-apilamiento y pre-apilamiento, de cinco paquetes comerciales disponibles en el mercado. Dentro de las características que se pueden observar en los datos generados tenemos que la banda de frecuencia espaciales y temporales permiten definir bien las estructuras; la relación seńal-ruido es suficientemente amplia como para resolver facilmente el objetivo; ademas el campo de velocidades de propagación en el medio es bien conocido, las mismas del modelo con el que se generaron los datos; por lo tanto, si no se obtiene una imagen bien enfocada del subsuelo, el principal motivo será por limitaciones del algoritmo de migración que se utilice. Los datos sintéticos fueron generados por trazado de rayos, a partir de un modelo que simula condiciones geológicas complejas con un campo de velocidades muy sencillo: dos capas de velocidad constante. EI modelo, se encuentra basado en el logotipo de la operadora venezolana CORPOVEN, SA (Filial de PDVSA). Sobre este objetivo, se simuló una adquisición sismica 2D para generar una sección de incidencia normal y registros de disparo común. EI resultado final es la comparación de las secciones migradas con los modelos originales y el análisis de los distintos ruidos y artefactos producidos por los operadores de migración.
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Demonstration of Migration Velocity Analysis Tomography on a Complex Structure
Authors R. Roundtree and C. StorkWe demonstrate an approach called MVA (Migration Velocity Analysis) tomography for determining an accurate velocity model for prestack depth migration. As a direct inversion method, this approach produces an accurate velocity model in significantly less time than iterative migration approaches. Moreover, as a tomographic technique that uses raypaths, this approach may resolve complex velocity models that cause problems for focusing analysis methods. In this paper we will illustrate via synthetic models why the MVA Tomographic Inversion technique provides improved results over the more common method of Focussing Analysis. Additionally, we will demonstrate on a geologically complex overthrust area how you can iterate and improve the migration velocity field through incorporating geologic constraints to the Tomographic Inversion.
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Relating Horizontal Resolution and Bandwidth after Migration
Authors D.A. Ebrom, S.A. Markley and J.A. McDonaldBefore migrations, horizontal resolution in seismic data is a function of both frequency and depth to target. After migration, the dependence of horizontal resolution on depth is removed, resulting from the collapse of the Fresnel zone to a smaller region. The horizontal extent of this smaller region Is predicted by plane wave theory to be controlled by the predomtnant frequency and the migration aperture. An essential point is that the presence of high frequencies in the wavelet (above the noise level) is important not just to the vertical resolution (which is relatively unaffected by migration) but also to the post-migration horizontal resolution. In order to experimentally verify this point, we collected physical-model seismic data over a model that had a variety of horizontal scale lengths. The data, which originally contained high frequencies, was low-pass filtered and the time-slices from high frequency and low frequency 3D seismic volumes were compared. The resolution losses are well explained by the predictions of plane wave theory.
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Two Methods for Subsurface Velocity and Structure Determination Based on RefiecHon Tomography
Authors D. Kosloff, E. Machet, Y. Falkowitz and Z. KorenPrestack depth migration has become a powerful tool for subsurface structure and velocity determination. We present two tomographic approaches that modify an initial model to produce an updated model which yields flatter prestack migration gathers. The first approach updates a model which consists of closed polygons and is suitable for situations where such a model can be interpreted from the data. The second approach is grid based and can allow a detachment between structure and velocity. Both approaches are derived from the tomographic principle. The spatial discretization yields, in both cases, a set of overdetermined linear equations which are solved by weighted least squares.
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Pattern Recognition Using Cluster Analysis Applied to Automated First Break Picking
By G. LiebhardtCluster analysis is a well-known statistical tool which is often applied when classification problems arise. The identification of first break signals may be interpreted as a specific classification or recognition problem. A "learning" classificator type is used to generate the initial database, which includes the manual choice of first breaks within some reference data and the calculation of probability densities describing the attribute space. Because the database may be updated during the automatic picking process, the system may adapt itself to changing signal and noise conditions.
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Imaging Alternatives Around Salt Bodies in the Gulf of Mexico
Authors S.Y.C. Lee, I.R. Mufti, G.A. Zelewski and N.J. House-FinchMobil has applied an arsenal of specific imaging techniques to a variety of salt related imaging problems in the Gulf of Mexico. The key to success in any imaging problem is close interaction between interpreters, velocity model builders, algorithm developers and computer hardware experts. What is presented is an array of different problems and associated technologies ranging from conventional 20 time processing to full 3D prestack depth migration as needed to solve specific geologic problems. These advanced technologies would not be possible without access to the latest fast thinking computers as well as an advanced computer network linking together the interpreter model builders, processors, mass storage devices and algorithm developers.
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An Iterative Procedure Employing Quasilinearization for Parameter Estimation in Acoustic Media
Authors E. Fernandez, P. Gauzellino and J.E. SantosAn iterative algorithm using quasilinenrization techniques to solve a parameter estimation problem for the acoustic wave equation in a single espace variable with absorbing boundary conditions depending on the parameter is described. The problem is formulated as the minimization of a quadratic cost functional. The derivative of the functional with respect to the parameter is obtained using the solution of a differentialequation similar to that of the direct problem. ' The non convexity of the cost functional is also adressed. Numerical examples are presented to illustrate the application of the algorithm.
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Removal of surface-related multiples from marine seismic data: A field data example
Authors R.G. van Borselen, J.T. Fokkema and P.M. van den BergRemoval of the effects of the free surface from seismic reflection data is an essential pre-processing step before pre-stack migration. The problem can be formulated by means of Rayleigh's reciprocity theorem which leads to an integral equation of the second kind for the desired pressure field, that does not include these free-surface effects. In order to solve the integral equation an estimate for the source wavelet is required. To obtain an accurate estimate for the source wavelet the minimum energy criterion is employed. The energy minimization problem is solved using a modified conjugate gradient method. As a result, a causal estimate for the source wavelet is obtained. The method is applied to a marine field data set and demonstrates the effectiveness of the procedure.
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Considerations on the Applications of the Parabolic Radon Transform
More LessDespite the wide use of the Parabolic Radon Transform in the context of multiple attenuation, some of its properties have not been discussed yet. These properties determine the best way of dealing with the Parabolic Radon Transform (PRT) in what concerns to both efficiency and CPU saving. Some common procedures in seismic processing like mute and NMO stretch have to be considered to avoid misuse of the PRT. This paper offers a discussion of important issues to deal with PRT. Some conclusions are based on theoretical predictions of the transform of an event with a hyperbolic moveout, taken here as representative of an ordinary situation in practice.
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