scholarly journals Comparative analysis of nonhyperbolic multiparametric travel-time approximations of multicomponent seismic data considering difference of depth between source and receiver using OBN technology

2019 ◽  
Vol 37 (4) ◽  
pp. 397
Author(s):  
Nelson Ricardo Coelho Flores Zuniga ◽  
Eder Cassola Molina ◽  
Renato Luiz Prado
Keyword(s):  
Comparative Analysis ◽  
Travel Time ◽  
Seismic Data ◽  
Complexity Analysis ◽  
Velocity Analysis ◽  
Ocean Bottom ◽  
Multicomponent Seismic ◽  
Calculated Curve ◽  
The Difference ◽  
Wave Conversion

AbstractThe processing of multicomponent seismic data is already a challenge concerning the velocity analysis. When it is performed for offshore survey, the difficulty increases a lot more with the use of OBN (Ocean Bottom Nodes) technology. The ray tracing asymmetry generated by the wave conversion and the difference of datum between source and receptor are not the only factors which contribute for a strongly nonhyperbolic travel-time event. The layered subsurface models and the large offsets employed in the offshore surveys make the nonhyperbolicity even stronger. Aiming to solve this problem, eight approximations to perform the velocity analysis were tested for two models. The complexity analysis of each nonhyperbolic multiparametric approximation was also studied to understand their behaviors during the optimization process. The relative error between the observed curve and the calculated curve with each approximation was computed for PP and PS reflection events of two models. With these informations, it was possible to determine which approximation is the most reliable one for this kind of models.Keywords: multicomponent, OBN, nonhyperbolic, multiparametric. ResumoO processamento de dados sísmicos multicomponentes já é um desafio com relação à análise de velocidades. Quando realizado para levantamentos marítimos, a dificuldade aumenta muito mais com o uso da tecnologia OBN (Ocean Bottom Nodes). A assimetria no traçado de raios gerada pela conversão de onda e pela diferença de profundidade entre fonte e receptor não são os únicos fatores que contribuem para um evento de tempos de trânsito fortemente não-hiperbólico. Os modelos estratificados de subsuperfície e os grandes afastamentos aplicados nos levantamentos marítimos tornam a não-hiperbolicidade ainda mais forte. Visando resolver este problema, oito aproximações para realizar a análise de velocidades foram testadas para dois modelos. A análise de complexidade de cada aproximação não-hiperbólica multiparamétrica também foi estudada para entender seus comportamentos durante o processo de otimização. Os erros relativos entre as curvas observadas e calculadas com cada aproximação foram calculados para os eventos de reflexão PP e PS dos dois modelos. Com estas informações, foi possível determinar qual aproximação é a mais confiável para estes tipos de modelos.Palavras-chave: multicomponente, OBN; não-hiperbólico, multiparamétrico.

scholarly journals COMPARISON OF TRAVEL-TIME APPROXIMATIONS FOR UNCONVENTIONAL RESERVOIRS FROM SANTOS BASIN

2017 ◽  
Vol 35 (4) ◽  
pp. 273 ◽  
Author(s):  
Nelson Ricardo Coelho Flores Zuniga ◽  
Eder Cassola Molina ◽  
Renato Luiz Prado
Keyword(s):  
Travel Time ◽  
Complexity Analysis ◽  
Numerical Study ◽  
Optimization Criterion ◽  
Hydrocarbon Exploration ◽  
Unconventional Reservoirs ◽  
Ocean Bottom ◽  
Converted Wave ◽  
Reflection Seismic ◽  
Multicomponent Seismic

ABSTRACT. The reflection seismic method is extremely important for the hydrocarbon exploration. With more complex geological structures, as the pre-salt from Santos Basin, the reservoir exploration becomes more challenging and the multicomponent seismic investigation improves its mapping and characterization. To obtain multicomponent seismic data of an offshore survey it is necessary to use the OBN (Ocean Bottom Nodes) technology. The converted wave behavior, the large offsets and the difference of datum between source and receptors for layered media, results in strong nonhyperbolic travel-time events. Furthermore, the complexity and peculiarities of some unconventional reservoirs found in the pre-salt also increase the difficulty to perform the velocity analysis. For these reasons, it is necessary to use nonhyperbolic multiparametric travel-time approximations to control the nonhyperbolicity. Here we perform the comparison of nonhyperbolic travel-time approximations of seismic reflection events derived from geological models. The numerical study was considered as an inverse problem and it was treated according to an optimization criterion. The complexity analysis was performed in order to understand the behavior of each approximation concerning the unicity. After the computation of the relative errors between the observed curve and the calculated curve for each nonhyperbolic approximation, it was possible to find out the one with the highest accuracy for the events tested here.  Keywords:  multicomponent, OBN, nonhyperbolic.RESUMO.Ométodo sísmico de reflexão é extremamente importante para a exploração de hidrocarbonetos. Comestruturas geológicasmais complexas, como o pré-sal da Bacia de Santos, a exploração de reservatórios se tornamais desafiadora e a utilização da sísmica multicomponente promove o mapeamento e caracterização estrutural. Para obter-se dados de sísmica multicomponente em um levantamento offshore é necessário utilizar a tecnologia OBN (Ocean Bottom Nodes ). O comportamento de ondas convertidas, longos afastamentos e diferença de datum entre fonte e receptor pra meios estratificados resultam em uma forte não-hiperbolicidade dos eventos de tempos de trânsito. Além disso, a complexidade e peculiaridades, de alguns reservatórios não convencionais encontrados no pré-sal, também aumentam a dificuldade em realizar a análise de velocidades. Por estes motivos, é necessário usar aproximações não-hiperbólicas multiparamétricas de tempos de trânsito para controlar os efeitos da não-hiperbolicidade. No presente trabalho, foi realizada a comparação de aproximações não-hiperbólicas de tempos de trânsito de eventos sísmicos de reflexão provenientes de modelos geológicos. O estudo numérico foi considerado como um problema inverso e foi tratado de acordo com um critério de otimização. A análise de complexidade foi realizada para compreender o comportamento de cada aproximação com respeito a unicidade. Após computar os erros relativos entre a curva observada e as calculadas com cada aproximação, foi possível descobrir a aproximação que apresentou maior precisão para os testes realizado.Palavras-chave: multicomponente, OBN, não-hiperbólicas.

Comparison of nonhyperbolic travel-time approximations for multicomponent seismic data

2015 ◽  
Author(s):  
Nelson Ricardo Coelho Flores Zuniga* ◽  
Oleg Bokhonok ◽  
Liliana Alcazar Diogo
Keyword(s):  
Travel Time ◽  
Seismic Data ◽  
Multicomponent Seismic

A New NMO Method Based on Non-Hyperbolic Reflection Event

2013 ◽  
Vol 718-720 ◽  
pp. 343-346
Author(s):  
Yong Ge ◽  
Yu Hong Xie ◽  
Lie Li ◽  
Jiao Deng He ◽  
Tian Cai Li ◽  
...  
Keyword(s):  
Travel Time ◽  
Seismic Data ◽  
Velocity Analysis

The conventional velocity analysis and normal moveout (NMO) are based on hyperbolic event, but the assumption of hyperbolic travel-time only applies to the situation where offset is less than or equal to the depth of reflecting interface. In recent years, in order to explore the new domain in deeper region, acquisition and processing about seismic data are developed rapidly. Maximum offset of acquisition has been reached or more than 8000 meters, and the coverage reached 100 times too. So the conventional hyperbolic normal moveout is not suitable for long cable acquisition. To solve the problems led by long array, this paper introduces the long array non hyperbolic NMO method, and it works well both in the model and practical data.

Integrated 2D 4-C OBC velocity analysis of near-seafloor sediments, Green Canyon, Gulf of Mexico

Geophysics ◽  
2008 ◽  
Vol 73 (6) ◽  
pp. B109-B115 ◽  
Author(s):  
Michael V. DeAngelo ◽  
Paul E. Murray ◽  
Bob A. Hardage ◽  
Randy L. Remington
Keyword(s):  
Seismic Data ◽  
Velocity Analysis ◽  
Ocean Bottom ◽  
Reflection Mode ◽  
Velocity Models ◽  
Velocity Information ◽  
Interval Velocities ◽  
Seafloor Sediments ◽  
Vital Element

Using 2D four-component ocean-bottom-cable (2D 4-C OBC) seismic data processed in common-receiver gathers, we developed robust [Formula: see text] and [Formula: see text] interval velocities for the near-seafloor strata. A vital element of the study was to implement iterative interpretation techniques to correlate near-seafloor P-P and P-SV images. Initially, depth-equivalent P-P and P-SV layers were interpreted by visually matching similar events in both seismic modes. Complementary 1D ray-tracing analyses then determined interval values of subsea-floor [Formula: see text] and [Formula: see text] velocities across a series of earth layers extending from the seafloor to below the base of the hydrate stability zone (BHSZ) to further constrain these interpretations. Iterating interpretation of depth-equivalent horizons with velocity analyses allowed us to converge on physically reasonable velocity models. Simultaneous [Formula: see text] and [Formula: see text] velocity analysis provided additional model constraints in areas where data quality of one reflection mode (usually [Formula: see text] in the near-seafloor environments) would not provide adequate information to derive reliable velocity information.

Rayleigh-Marchenko redatuming for target-oriented, true-amplitude imaging

Geophysics ◽  
2017 ◽  
Vol 82 (6) ◽  
pp. S439-S452 ◽  
Author(s):  
Matteo Ravasi
Keyword(s):  
Seismic Data ◽  
Field Data ◽  
Scaling Factor ◽  
Velocity Analysis ◽  
Ocean Bottom ◽  
Structural Imaging ◽  
Dual Sensor ◽  
Band Limited ◽  
Borehole Seismic ◽  
Amplitude Versus

Marchenko redatuming is a revolutionary technique to estimate Green’s functions from virtual sources in the subsurface using only data measured at the earth’s surface, without having to place either sources or receivers in the subsurface. This goal is achieved by crafting special wavefields (so-called focusing functions) that can focus energy at a chosen point in the subsurface. Despite its great potential, strict requirements on the reflection response such as knowledge and accurate deconvolution of the source wavelet (including absolute scaling factor) and co-location of sources and receivers have so far challenged the application of Marchenko redatuming to real-world scenarios. I combine the coupled Marchenko equations with a one-way version of the Rayleigh integral representation to obtain a new redatuming scheme that handles internal as well as free-surface multiples using dual-sensor, band-limited seismic data (with an unknown source signature) from any acquisition system that presents arbitrarily located sources above a line of regularly sampled receivers—for example, ocean-bottom, source-over-spread streamer, and horizontal borehole seismic data. The redatuming scheme is validated using synthetic and field data, and the retrieved subsurface wavefields are used for improved structural imaging and taken as input for the computation of true-amplitude angle gathers, which can lead to more accurate amplitude-versus-angle interpretation and velocity analysis.

Vector-wave-based elastic reverse time migration of ocean-bottom 4C seismic data

Geophysics ◽  
2018 ◽  
Vol 83 (4) ◽  
pp. S333-S343 ◽  
Author(s):  
Pengfei Yu ◽  
Jianhua Geng ◽  
Jiqiang Ma
Keyword(s):  
Seismic Data ◽  
Ocean Bottom ◽  
Reverse Time ◽  
Reverse Time Migration ◽  
S Wave ◽  
Vector Wave ◽  
S Waves ◽  
Time Migration ◽  
Multicomponent Seismic ◽  
Wavefield Extrapolation

The acoustic-elastic coupled equation (AECE) has several advantages when compared with conventional scalar-wave-based elastic reverse time migration (ERTM) methods used to image ocean-bottom multicomponent seismic data. In particular, vector-wave-based ERTM requires vectorial P- and S-waves on the source and receiver sides, but these cannot be directly obtained from wavefield extrapolation using AECE. Therefore, we have developed a P- and S-wave vector decomposition (VD) approach within AECE; this approach enables the deduction of a novel VD-based AECE, from which vectorial P- and S-waves can be obtained directly via wavefield extrapolation. We are also able to derive a new formulation suitable for vector-wave-based ERTM of ocean-bottom multicomponent seismic data that can generate a phase-preserved PS-image. Three synthetic examples illustrate the validity and effectiveness of our new method.

FINANCIAL CONTROLLING IN THE SYSTEM OF FINANCIAL MANAGEMENT

2018 ◽  
Vol 28 (1) ◽  
pp. 137-141
Author(s):  
Petya Yordanova – Dinova
Keyword(s):  
Comparative Analysis ◽  
Financial Management ◽  
Financial Stability ◽  
Business Environment ◽  
Innovative Approach ◽  
Financial Sustainability ◽  
The Common ◽  
The Difference ◽  
Effective Use ◽  
And Control

This paper explores the comparative analysis of the financial controlling, who is a result from the common controlling concept and the financial management. In the specialized literature, financial controlling is seen as an innovative approach to financial management. It is often presented as the most promising instrument of financial diagnostics. Generally speaking, financial controlling is seen as a process of managing the company`s assets which are valued in monetary measures. The difference between the financial management and the financial controlling is that the second covers all functions of management, analysis and control of finances, aiming at maximizing their effective use and increasing the value of the enterprise. Financial controlling is often seen as a function of the common practice of financial management. Its objective is to preserve the financial stability and financial sustainability of enterprises operating in a highly aggressive business environment.

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