Review of Cunningham et al. The Impact of Seismic Interpretation Methods on the Analysis of Faults: A Case Study from the Snøhvit Field, Barents Sea

Abstract. Five seismic interpretation experiments were conducted on an area of interest containing a fault relay in the Snøhvit field, Barents Sea, Norway, to understand how the interpretation method impacts the analysis of fault and horizon morphologies, fault lengths, and throw. The resulting horizon and fault interpretations from the least and most successful interpretation methods were further analysed to understand their impact on geological modelling and hydrocarbon volume calculation. Generally, the least dense manual interpretation method of horizons (32 inlines and 32 crosslines; 32 ILs × 32 XLs, 400 m) and faults (32 ILs, 400 m) resulted in inaccurate fault and horizon interpretations and underdeveloped relay morphologies and throw, which are inadequate for any detailed geological analysis. The densest fault interpretations (4 ILs, 50 m) and 3D auto-tracked horizons (all ILs and XLs spaced 12.5 m) provided the most detailed interpretations, most developed relay and fault morphologies, and geologically realistic throw distributions. Sparse interpretation grids generate significant issues in the model itself, which make it geologically inaccurate and lead to misunderstanding of the structural evolution of the relay. Despite significant differences between the two models, the calculated in-place petroleum reserves are broadly similar in the least and most dense experiments. However, when considered at field scale, the differences in volumes that are generated by the contrasting interpretation methodologies clearly demonstrate the importance of applying accurate interpretation strategies.

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A case study on semiautomatic seismic interpretation of unconformities and faults in the southwestern Barents Sea

Interpretation ◽

10.1190/int-2017-0152.1 ◽

2018 ◽

Vol 6 (2) ◽

pp. SD29-SD40 ◽

Cited By ~ 2

Author(s):

Aina J. Bugge ◽

Stuart R. Clark ◽

Jan E. Lie ◽

Jan I. Faleide

Keyword(s):

Barents Sea ◽

Seismic Interpretation ◽

Connected Components ◽

Normal Faults ◽

Morphological Operations ◽

Image Region ◽

The North ◽

Seismic Amplitudes ◽

Cenozoic Sediments

Recently, there has been a growing interest in automatic and semiautomatic seismic interpretation, and we have developed methods for extraction of 3D unconformities and faults from seismic data as alternatives to conventional and time-consuming manual interpretation. Our methods can be used separately or together, and they are time efficient and based on easily available 2D and 3D image-processing algorithms, such as morphological operations and image region property operations. The method for extraction of unconformities defines seismic sequences, based on their stratigraphic stacking patterns and seismic amplitudes, and extracts the boundaries between these sequences. The fault-extraction method extracts connected components from a coherence-based fault-likelihood cube where interfering objects are addressed prior to the extraction. We have used industry-based data acquired in a complex geological area and implemented our methods with a case study on the Polhem Subplatform, located in the southwestern Barents Sea north of Norway. For this case study, our methods result in the extraction of two unconformities and twenty-five faults. The unconformities are assumed to be the Base Pleistocene, which separates preglacial and postglacial Cenozoic sediments, and the Base Cretaceous, which separates the severely faulted Mesozoic strata from prograding Paleocene deposits. The faults are assumed to be mainly Jurassic normal faults, and they follow the trends of the eastern and southwestern boundaries of the Polhem Subplatform; the north–south-trending Jason Fault complex; and the northwest–southeast-trending Ringvassøy-Loppa Fault complex.

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The Impact of High-Resolution Biostratigraphy on Reservoir Prediction and Basin History--A Barents Sea Case Study

AAPG Bulletin ◽

10.1306/0c9b1ba1-1710-11d7-8645000102c1865d ◽

1991 ◽

Vol 75 ◽

Author(s):

HUSMO, TORE, Esso Norge, Forus, Nor

Keyword(s):

High Resolution ◽

Barents Sea ◽

Reservoir Prediction ◽

The Impact

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The Impact of Seismic Interpretation Methods on the Analysis of Faults: A Case Study from the Snøhvit Field, Barents Sea

10.5194/se-2020-174 ◽

2020 ◽

Author(s):

Jennifer Cunningham ◽

Nestor Cardozo ◽

Chris Townsend ◽

Richard Callow

Keyword(s):

Barents Sea ◽

Structural Evolution ◽

Vertical Displacement ◽

Seismic Interpretation ◽

Volume Calculation ◽

Area Of Interest ◽

Geological Modelling ◽

X 32 ◽

The Impact ◽

Interpretation Method

Abstract. Five seismic interpretation experiments were conducted on an area of interest containing a fault relay in the Snøhvit field, Barents Sea, Norway, to understand how interpretation method impacts the analysis of fault and horizon morphologies, fault lengths, and vertical displacement (throw). The resulting horizon and fault interpretations from the least and most successful interpretation methods were further analysed to understand the impact of interpretation method on geological modelling and hydrocarbon volume calculation. Generally, the least dense manual interpretation method of horizons (32 inlines (ILs) x 32 crosslines (XLs), 400 m) and faults (32 ILs, 400 m) resulted in inaccurate fault and horizon interpretations and underdeveloped relay morphologies and throw that can be considered inadequate for any detailed geological analysis. The densest fault interpretations (4 ILs, 50 m) and auto-tracked horizons (1 IL x 1 XL, 12.5 m) provided the most detailed interpretations, most developed relay and fault morphologies and geologically realistic throw distributions. Analysis of the geological modelling proved that sparse interpretation grids generate significant issues in the model itself which make it geologically inaccurate and lead to misunderstanding of the structural evolution of the relay. Despite significant differences between the two models the calculated in-place petroleum reserves are broadly similar in the least and most dense experiments. However, when considered at field-scale the magnitude of the differences in volumes that are generated solely by the contrasting interpretation methodologies clearly demonstrates the importance of applying accurate interpretation strategies.

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IMPACTS OF SEISMIC VELOCITY MODEL CALIBRATION FOR TIME-DEPTH CONVERSION:A CASE STUDY

Brazilian Journal of Geophysics ◽

10.22564/rbgf.v36i4.1965 ◽

2018 ◽

Vol 36 (4) ◽

pp. 1

Author(s):

Frank Cenci Bulhões ◽

Gleidson Diniz Ferreira ◽

José Fernando Caparica Jr.

Keyword(s):

Model Building ◽

Seismic Velocity ◽

Velocity Model ◽

Seismic Interpretation ◽

Time Data ◽

Velocity Modeling ◽

Seismic Resolution ◽

Velocity Model Building ◽

The Impact

ABSTRACT. In this work we discuss the impact of the uncertainties in the seismic interpretation on the velocity model building and time-depth conversion. The case study presented is located in the Campos Basin, Brazil. The main objective of this work is to show how the input data and the parameters affect substantially the velocity modeling. The methodology uses velocity model building methods and calibration parameters to integrate seismic interpretation and wells. It presents scenarios with calibration by time-depth tables and horizons-geological markers. The data converted to depth are compared to the time data and the geological markers. The data converted by the calibrated model with horizon-marker presented smaller differences compared to the markers and lower correlations in the pseudo-impedance. In the time-depth table calibration scenarios, the differences of the horizons compared to the markers were higher, but in the range of the seismic resolution and higher correlations.Keywords: seismic migration; wells; geological markers; exploration; interpretation.RESUMO. Neste trabalho é apresentado como as incertezas na interpretação sísmica impactam na cons-trução do modelo de velocidades e na conversão tempo-profundidade resultante. A área de estudo de estudo está localizada na Bacia de Campos, Brasil. O principal objetivo deste trabalho é mostrar como os dados de entrada e parâmetros afetam na modelagem de velocidade e conversão tempo x profundidade. A metodologia é comparar três diferentes cenários para calibração da velocidade de processamento e imageamento com as interpretações sísmicas e de poços: o cenário 1 utiliza ajuste por horizonte com marcador geológico e raio de influência 5 km; no cenário 2 é utilizada as tabelas tempo-profundidade, raio de influência 5 km por krigagem com derivada externa; e o cenário 3 utilizou-se tabelas tempo-profundidade, raio de influência 2 km por krigagem com deriva externa. O controle de qualidade dos três modelos de velocidade são avaliados pela conversão dos horizontes, seções sísmicas e perfis de pseudo-impedância. No cenário 1, os horizontes convertidos apresentam menores diferenças de profundidade em relação aos marcadores comparados aos demais cenários. Por outro lado, os cenários 2 e 3 apresentam maiores correlações entre o sismograma sintético e a seção sísmica convertida para o cenário 1.Palavras-chave: migração sísmica; poços; marcadores geológicos; exploração; interpretação.

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