Interpretation of four-component seismic data in a gas cloud area of the central Gulf of Mexico

Englehart, Thomas; Randazzo, Santi; Bertagne, Allen; Cafarelli, Bill

doi:10.1190/1.1438960

Cited by 18 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many efforts in seismic processing have been devoted to solving the problem of quality degradation and filtering the impact of gas chimneys on seismic sections (Dunbar et al, 1998;Englehart et al, 2001). In addition to the filtering techniques, tomography, seismic acquisition of shear waves and neural network that combine the use of different seismic attributes with this purpose (Aminzadeh et al, 2002).…”

Section: Methodology Seismic Processing To Optimize the Identification Of Gas Chimneysmentioning

confidence: 99%

Optimized Characterization of Gas Chimneys Based on Special Seismic Processing

Goulart¹,

Castro²,

Amorim³

2019

Braz J Geophys

View full text Add to dashboard Cite

A new computational methodology was developed to facilitate the interpretation of gas chimneys in seismic sections by analyzing the frequency spectrum of the seismic signal in the Hilbert Domain. Gas chimneys are structures associated with the migration of hydrocarbons or free gas, causing vertical chaotic disturbances in the seismic data. Its occurrence in oil reservoirs is considered an important indicator of the presence of an active petroleum system and its mapping is useful to reduce exploratory risks, increasing the probability of success of the pioneer wells. Standard seismic processing does not favor the recognition of gas chimneys, since their characteristic seismic signature is treated as noise and the low frequencies are strongly attenuated already in the period of the seismic acquisition. The set of reflections is calculated to enhance the low frequencies, making the gas chimneys easily identifiable in the seismic sections where they were not previously even perceived. The special processing flow was applied to seismic data from the Parnaíba Basin “(NE Brazil). This Paleozoic basin is especially rich in gas chimneys, which were favored by transcurrent tectonics associated with the Transbrasiliano Lineament. The gas chimneys interpretation could be validated by the observation of correlated seismic, topographic and geochemical features.KEYWORDS: special processing, gas chimney, exploratory risk, Parnaíba Basin. RESUMO. Uma nova metodologia computacional foi desenvolvida para facilitar a interpretação de chaminés de gás em seções sísmicas por meio da análise do espectro de frequência do sinal sísmico no Domínio de Hilbert. Chaminés de gás são estruturas associadas à migração de hidrocarbonetos ou gás livre, provocando perturbações caóticas verticais no dado sísmico. Sua ocorrência em reservatórios petrolíferos é considerada um importante indicador da presença de um sistema petrolífero ativo e seu mapeamento é útil para reduzir os riscos exploratórios, aumentando a probabilidade de sucesso dos poços pioneiros. O processamento sísmico padrão não favorece o reconhecimento das chaminés de gás, uma vez que a sua assinatura sísmica característica é tratada como ruído e as baixas frequências são fortemente atenuadas já no período da aquisição sísmica. O conjunto de reflexões é calculado para realçar as baixas frequências, tornando as chaminés de gás facilmente identificáveis nas seções sísmicas onde antes não eram nem percebidas. O processamento especial foi aplicado em dados sísmicos da Bacia do Parnaíba. Esta bacia paleozoica é especialmente rica em chaminés de gás, cuja presença foi favorecida pela tectônica transcorrente associada ao Lineamento Transbrasiliano. As chaminés de gás interpretadas puderam também ser validadas pela observação de feições sísmicas, topográficas e geoquímicas correlatas.Palavras-chave: processamento especial, chaminé de gás, risco exploratório, Bacia do Parnaíba.

show abstract

Section: Methodology Seismic Processing To Optimize the Identification Of Gas Chimneysmentioning

confidence: 99%

Optimized Characterization of Gas Chimneys Based on Special Seismic Processing

Goulart¹,

Castro²,

Amorim³

2019

Braz J Geophys

View full text Add to dashboard Cite

show abstract

“…Many efforts have been devoted to deal with this problem and filter out the impact of gas clouds and provide interpretable sections by imaging through them. Aside from different filtering techniques, tomography, and shear wave information have been used, for example, Dunbar (1998) and Englehart (2001), to accomplish this. While this paper also deals with gas clouds and gas chimneys, the main focus is to highlight such events and establish a link between chimney characteristics (occurrence, type and extent) and different geological features or exploration questions.…”

Section: Introductionmentioning

confidence: 99%

Interpretation of gas chimney volumes

Aminzadeh¹,

Connolly²,

Groot³

2002

SEG Technical Program Expanded Abstracts 2002

View full text Add to dashboard Cite

SummaryIn this paper we describe how seismically derived gas chimneys can be used to determine hydrocarbon migration paths. The emphasis will be on how to interpret chimney cubes. Through several case history examples, we will show chimney cubes can reveal vertical hydrocarbon migration paths that can be interpreted from their source into reservoir traps all the way to the surface. We will highlight distinguishing features of chimneys for oil-prone versus gas-prone prospects, and those related to separating active fault migration pathways. Further, we will show chimneys can support charging of shallow reservoirs. Our understanding of the petroleum system can improve by combining gas chimney data with other information. As such a chimney cube can be seen as a new exploration tool.

show abstract

Multi-attribute and Artificial Neural Network Analysis of Seismic Inferred Chimney-like Features in Marine Sediments: A Study from KG Basin, India

Ramu

Sain

2021

Journal of the Geological Society of India

View full text Add to dashboard Cite

In marine seismic sections, features like “chimneys”, characterized by low similarity chaotic zones or vertical disordered characteristics arise due to migration of gas. Numerous interpretation tools have been developed for the identification of chimney features from seismic data. Here, a study over a 2D seismic reflection profile, acquired by CSIR-National Geophysical Research Institute (NGRI), Hyderabad in the Krishna-Godavari (KG) basin in 2010 was carried out. The data is optimally conditioned or post-processed before extracting the attributes such as the similarity, dip variance, energy, and frequency washout, to capture the chimneys on seismic data. Finally, the attributes are combined and trained over interpreter’s acquaintances through a non-linear multi-layer perceptron (MLP) neural network to compute a hybrid attribute, defined as the chimney meta-attribute. The neural training results into an overall normalized root mean squared (RMS) error of 0.6 to 0.7 between the train and test data sets. Three chimneys of ~1.5, ~0.9, ~1.3 km heights are observed over the seismic line. As chimneys represent gas migration paths, the computation of chimney attribute helps in understanding the genesis of gas-hydrates not only in the KG basin, studied here, but also in any other prospective basin.

show abstract

Interpretation of four-component seismic data in a gas cloud area of the central Gulf of Mexico

Cited by 18 publications

References 0 publications

Optimized Characterization of Gas Chimneys Based on Special Seismic Processing

Optimized Characterization of Gas Chimneys Based on Special Seismic Processing

Interpretation of gas chimney volumes

Multi-attribute and Artificial Neural Network Analysis of Seismic Inferred Chimney-like Features in Marine Sediments: A Study from KG Basin, India

Contact Info

Product

Resources

About