Seismic attributes and structural interpretation—it takes two to tango...

2012 ◽  
Vol 52 (1) ◽  
pp. 437 ◽  
Author(s):  
Guillaume Backé ◽  
Ernest Swierczek ◽  
Justin MacDonald ◽  
Adam Bailey ◽  
David Tassone ◽  
...  
Keyword(s):  
Structural Information ◽  
Median Filter ◽  
Seismic Attributes ◽  
3D Seismic ◽  
Seismic Amplitude ◽  
The North ◽  
Amplitude Data ◽  
Fracture Models ◽  
Processing Techniques

In this paper, different 3D seismic attributes calculated to improve the accuracy and robustness of structural interpretations in several energy-rich Australian basins are compared. Detailed and precise fault and fracture maps are crucial not only for initial petroleum play assessment, but also for fault seal analysis and reservoir integrity studies. Robust fault and fracture models are also needed to improve the design of reservoir simulation programs and to manage the long-term containment of gas in geological formations. Different attributes (including coherency, dip-steered similarity, dip-steered median filter, dip-steered variance, apparent dip, and dip-steered most-positive and most-negative curvatures) from an array of 3D seismic datasets to better image structural fabrics, such as normal and different fractures patterns, in the North Perth, Cooper, Ceduna, Otway and Gippsland basins have been calculated. The results provide a remarkable improvement in the quality and precision of structural maps using this multi-attribute mapping workflow by comparison with more conventional maps produced, solely using seismic amplitude data. The key to the successful application of multi-attribute structural analysis, however, remains with the ability of the interpreter to identify meaningful structural information from a large volume of data. Thus, the structural expertise of the interpreter remains as the cornerstone to making geological sense of the various seismic processing techniques available.

Unsupervised machine learning using 3D seismic data applied to reservoir evaluation and rock type identification

2021 ◽  
pp. 1-69
Author(s):  
Marwa Hussein ◽  
Robert R. Stewart ◽  
Deborah Sacrey ◽  
Jonny Wu ◽  
Rajas Athale
Keyword(s):  
Machine Learning ◽  
Seismic Data ◽  
Rock Type ◽  
Seismic Attributes ◽  
Reservoir Quality ◽  
3D Seismic ◽  
Reservoir Properties ◽  
Unsupervised Machine Learning ◽  
Amplitude Data ◽  
3D Seismic Data

Net reservoir discrimination and rock type identification play vital roles in determining reservoir quality, distribution, and identification of stratigraphic baffles for optimizing drilling plans and economic petroleum recovery. Although it is challenging to discriminate small changes in reservoir properties or identify thin stratigraphic barriers below seismic resolution from conventional seismic amplitude data, we have found that seismic attributes aid in defining the reservoir architecture, properties, and stratigraphic baffles. However, analyzing numerous individual attributes is a time-consuming process and may have limitations for revealing small petrophysical changes within a reservoir. Using the Maui 3D seismic data acquired in offshore Taranaki Basin, New Zealand, we generate typical instantaneous and spectral decomposition seismic attributes that are sensitive to lithologic variations and changes in reservoir properties. Using the most common petrophysical and rock typing classification methods, the rock quality and heterogeneity of the C1 Sand reservoir are studied for four wells located within the 3D seismic volume. We find that integrating the geologic content of a combination of eight spectral instantaneous attribute volumes using an unsupervised machine-learning algorithm (self-organizing maps [SOMs]) results in a classification volume that can highlight reservoir distribution and identify stratigraphic baffles by correlating the SOM clusters with discrete net reservoir and flow-unit logs. We find that SOM classification of natural clusters of multiattribute samples in the attribute space is sensitive to subtle changes within the reservoir’s petrophysical properties. We find that SOM clusters appear to be more sensitive to porosity variations compared with lithologic changes within the reservoir. Thus, this method helps us to understand reservoir quality and heterogeneity in addition to illuminating thin reservoirs and stratigraphic baffles.

REDUCING RESOURCE UNCERTAINTY USING SEISMIC AMPLITUDE ANALYSIS ON THE SOUTHERN RANKIN TREND, NORTHWEST AUSTRALIA

1999 ◽  
Vol 39 (1) ◽  
pp. 128 ◽  
Author(s):  
D. Sibley ◽  
F. Herkenhoff ◽  
D. Criddle ◽  
M. McLerie
Keyword(s):  
Seismic Attributes ◽  
3D Seismic ◽  
Amplitude Analysis ◽  
Seismic Amplitude ◽  
Amplitude Versus Offset ◽  
Minimum Number ◽  
Gas Fields ◽  
Resource Uncertainty

Between 1973 and 1996 West Australian Petroleum Pty Limited (WAPET) discovered five major gas fields on the southern Rankin Trend including Spar, West Tryal Rocks, Gorgon, Chrysaor, and Dionysus (collectively termed the Greater Gorgon Resource). Recent discoveries at Chrysaor and Dionysus emphasise the role of subtle 3D seismic attributes in finding hydrocarbons and defining reserves with a minimum number of wells.The Gorgon, Chrysaor, and Dionysus fields were covered by 3D seismic data shot in 1991 and 1995, which led WAPET to discover Chrysaor and later Dionysus. Subsequent to the 3D acquisitions, field reservoirs have been correlated with anomalous seismic events (seismic amplitude and amplitude versus offset) that conform to depth structure. Follow-up work has shown that combining these 3D seismic attributes improves the prediction of wet sands, gas sands, and other lithologies.The resulting understanding and confidence provided by this 3D seismic has driven an aggressive exploration program and defined field reserves at a high confidence level. Results include the recent award of permit area WA-267-P to WAPET and the ongoing studies to begin development of the Greater Gorgon Resource.

Identification of polygonal faulting from legacy 3D seismic data in vintage Gulf of Mexico data using seismic attributes

2021 ◽  
pp. 1-17
Author(s):  
Karen M. Leopoldino Oliveira ◽  
Heather Bedle ◽  
Karelia La Marca Molina
Keyword(s):  
Seismic Data ◽  
Seismic Attributes ◽  
Fault System ◽  
3D Seismic ◽  
Seismic Attribute ◽  
Variable Amplitude ◽  
Attribute Analysis ◽  
Amplitude Data ◽  
3D Seismic Data ◽  
Polygonal Fault

We analyzed a 1991 3D seismic data located offshore Florida and applied seismic attribute analysis to identify geological structures. Initially, the seismic data appears to have a high signal-to-noise-ratio, being of an older vintage of quality, and appears to reveal variable amplitude subparallel horizons. Additional geophysical analysis, including seismic attribute analysis, reveals that the data has excessive denoising, and that the continuous features are actually a network of polygonal faults. The polygonal faults were identified in two tiers using variance, curvature, dip magnitude, and dip azimuth seismic attributes. Inline and crossline sections show continuous reflectors with a noisy appearance, where the polygonal faults are suppressed. In the variance time slices, the polygonal fault system forms a complex network that is not clearly imaged in the seismic amplitude data. The patterns of polygonal fault systems in this legacy dataset are compared to more recently acquired 3D seismic data from Australia and New Zealand. It is relevant to emphasize the importance of seismic attribute analysis to improve accuracy of interpretations, and also to not dismiss older seismic data that has low accurate imaging, as the variable amplitude subparallel horizons might have a geologic origin.

On the value of 3D seismic amplitude data to reduce uncertainty in the forecast of reservoir production

2006 ◽  
Vol 50 (3-4) ◽  
pp. 269-284 ◽  
Author(s):  
Omar J. Varela ◽  
Carlos Torres-Verdín ◽  
Larry W. Lake
Keyword(s):  
3D Seismic ◽  
Seismic Amplitude ◽  
Amplitude Data

Alternatives in Paleocene exploration West of Shetland: a case study

2004 ◽  
Vol 40 (2) ◽  
pp. 131-143 ◽  
Author(s):  
John R. Smallwood ◽  
David Prescott ◽  
Wayne Kirk
Keyword(s):  
Seismic Data ◽  
Seismic Attributes ◽  
Well Testing ◽  
3D Seismic ◽  
Seismic Amplitude ◽  
Magnetic Fabrics ◽  
3D Data ◽  
History Of ◽  
The Uk

SynopsisThis paper illustrates oil exploration in the West of Shetlands area from 1995 to 2001 by documenting the history of Block 205/9, awarded in the UK 16th Licensing Round in 1995. Good quality Paleocene sands had been encountered in the 1989 well 205/9-1 in the down-dip part of the block, and equivalent sands were absent on the adjacent Flett Ridge to the SE, setting up the possibility of a pinchout play. The first well testing the play, 205/8-1, was drilled on the overall pinchout on 2D seismic data, but 3D seismic data were acquired across the area to better delineate the depositional systems. The first well drilled on the 3D data to test the sand pinchout, 205/14-3, failed to encounter sands in communication with those in 205/9-1, so attention turned to alternative stratigraphic traps highlighted by seismic amplitude anomalies. Detailed evaluation of the seismic data revealed that the attractive seismic amplitude response of one potential prospect was actually an artefact associated with overlying basalt. Further analysis of the 3D seismic attributes identified a tongue of sand south of 205/9-1, and analysis of magnetic fabrics from core data in 205/9-1 revealed that sand was input to this area from the NE, contrary to previous models. Unfortunately the seismic attributes, supported by fluid inclusion data, suggested that the sand was water-wet. As a result of the evaluation work, the block was relinquished in 1999 without further drilling. While there is undoubtedly scope for stratigraphic traps in the area to prove hydrocarbon-bearing, experience on the 205/9 block and other studies led to a refocusing on dip-closed structures, and a resulting discovery, the first in the Faroes, consisted of 170 m of hydrocarbon-bearing sands in the T10 Paleocene interval.

scholarly journals APPLYING FILTERS AND SEISMIC ATTRIBUTES FOR ENHANCING FAULTS IN THE 3D SEISMIC SURVEY OF ALTO DE SIRIRIZINHO (SERGIPE-ALAGOAS BASIN, NORTHEAST BRAZIL)

2013 ◽  
Vol 31 (1) ◽  
pp. 109
Author(s):  
Arthur Victor Medeiros Francelino ◽  
Alex Francisco Antunes
Keyword(s):  
Seismic Data ◽  
Median Filter ◽  
Random Noise ◽  
Seismic Attributes ◽  
Oil Fields ◽  
Seismic Survey ◽  
Northeast Brazil ◽  
3D Seismic ◽  
3D Seismic Data

The 3D seismic data allow that mature oil fields be reevaluated in order to improve the characterization of faults that affect the flow of hydrocarbons. The use of seismic attributes and filtering allows an improvement in the identification and enhancement of these fractures on seismic data. In this study, we used two different filters: the dip-steered median filter to remove random noise and increase the lateral continuity of reflections, and the fault-enhancement filter used to enhance the discontinuities of the reflections. After filtering, similarity and curvature attributes were applied in order to identify the distribution of fractures along the data. Theuse of these attributes and filters contributed greatly to the identification and enhancement of the continuity of the fractures. RESUMO: Com o advento da sísmica 3D, campos de petróleo maduros podem ser reavaliados melhorando a caracterização das falhas que influenciam o fluxo de hidrocarbonetos. A utilização de filtragens e atributos sísmicos possibilita uma melhora na identificação e no realce dessas fraturas no dado sísmico. No presente trabalho foram utilizados dois tipos de filtros, sendo o dip-steered median filter, com a finalidade de retirar os ruídos aleatórios e aumentar a continuidade lateral das reflexões, e o fault-enhancement filter para realçar as descontinuidades das reflexões. Após a etapa de filtragem foram aplicados os atributos de similaridade e curvatura, para se identificar a distribuição das falhas. O uso dos atributos e filtragens colaborou fortemente para a identificação e o realce da continuidade das fraturas. Palavras-chave: reservatório fraturado; interpretação sísmica e atributos sísmicos

Long-term Cyclic Variations of Prominences, Green and Red Coronae over Solar Cycles

2000 ◽  
Vol 179 ◽  
pp. 201-204
Author(s):  
Vojtech Rušin ◽  
Milan Minarovjech ◽  
Milan Rybanský
Keyword(s):  
Emission Lines ◽  
High Latitudes ◽  
Green Line ◽  
Solar Cycles ◽  
The South ◽  
Coronal Emission ◽  
Local Maxima ◽  
The North ◽  
Cyclic Variations

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.

Long Term Changes in Wind and Wave Climate on the North Sea

1991 ◽  
Author(s):  
Frank M. J. Hoozemans
Keyword(s):  
North Sea ◽  
Wave Climate ◽  
The North ◽  
Long Term Changes ◽  
The North Sea

Mafias on the Move

2011 ◽  
Author(s):  
Federico Varese
Keyword(s):  
United States ◽  
New York ◽  
Organized Crime ◽  
The United States ◽  
The West ◽  
Market Expansion ◽  
The North ◽  
Economic Transformations ◽  
At Will

Organized crime is spreading like a global virus as mobs take advantage of open borders to establish local franchises at will. That at least is the fear, inspired by stories of Russian mobsters in New York, Chinese triads in London, and Italian mafias throughout the West. As this book explains, the truth is more complicated. The author has spent years researching mafia groups in Italy, Russia, the United States, and China, and argues that mafiosi often find themselves abroad against their will, rather than through a strategic plan to colonize new territories. Once there, they do not always succeed in establishing themselves. The book spells out the conditions that lead to their long-term success, namely sudden market expansion that is neither exploited by local rivals nor blocked by authorities. Ultimately the inability of the state to govern economic transformations gives mafias their opportunity. In a series of matched comparisons, the book charts the attempts of the Calabrese 'Ndrangheta to move to the north of Italy, and shows how the Sicilian mafia expanded to early twentieth-century New York, but failed around the same time to find a niche in Argentina. The book explains why the Russian mafia failed to penetrate Rome but succeeded in Hungary. A pioneering chapter on China examines the challenges that triads from Taiwan and Hong Kong find in branching out to the mainland. This book is both a compelling read and a sober assessment of the risks posed by globalization and immigration for the spread of mafias.

CURRENT STATE AND DEVELOPMENT PERSPECTIVES OF THE CASPIAN SPRAT FISHERIES

2018 ◽  
pp. 69-75
Author(s):  
Tatiana Vasilievna Pomogaeva ◽  
Aliya Ahmetovna Aseinova ◽  
Yuriy Aleksandrovich Paritskiy ◽  
Vjacheslav Petrovich Razinkov
Keyword(s):  
Food Item ◽  
Growth Potential ◽  
North West ◽  
Marine Fishery ◽  
The North ◽  
Current State ◽  
West Part ◽  
Eggs And Larvae ◽  
Intensive Growth

The article presents annual statistical data of the Caspian Research Institute of Fishery. There has been kept track of the long term dynamics of the stocks of three species of Caspian sprat (anchovy, big-eyed kilka, sprat) and investigated a process of substituting a food item of sprats Eurytemora grimmi to a small-celled copepod species Acartia tonsa Dana. According to the research results, there has been determined growth potential of stocks of each species. Ctenophoran-Mnemiopsis has an adverse effect on sprat population by eating fish eggs and larvae. Ctenophoram - Mnemiopsis is a nutritional competitor to the full-grown fishes. The article gives recommendations on reclamation of stocks of the most perspective species - common sprat, whose biological characteristics helped not to suffer during Ctenophoram outburst and to increase its population during change of the main food item. Hydroacoustic survey data prove the intensive growth of common sprat biomass in the north-west part of the Middle Caspian. According to the results of the research it may be concluded that to realize the volumes of recommended sprat catch it is necessary to organize the marine fishery of common sprat at the Russian Middle Caspian shelf.

Sign in / Sign up

Export Citation Format

Share Document