Origin of seafloor pockmarks overlying submarine landslides: Insights from semi-automated mapping of 3D seismic horizons (North West Shelf, Australia)

The newly acquired 3,590 km2 Demeter 3D high resolution seismic survey covers most of the North West Shelf Venture (NWSV) area; a prolific hydrocarbon province with ultimate recoverable reserves of greater than 30 Tcf gas and 1.5 billion bbls of oil and natural gas liquids. The exploration and development of this area has evolved in parallel with the advent of new technologies, maturing into the present phase of revitalised development and exploration based on the Demeter 3D.The NWSV is entering a period of growing gas market demand and infrastructure expansion, combined with a more diverse and mature supply portfolio of offshore fields. A sequence of satellite fields will require optimised development over the next 5–10 years, with a large number of wells to be drilled.The NWSV area is acknowledged to be a complex seismic environment that, until recently, was imaged by a patchwork of eight vintage (1981–98) 3D seismic surveys, each acquired with different parameters. With most of the clearly defined structural highs drilled, exploration success in recent years has been modest. This is due primarily to severe seismic multiple contamination masking the more subtle and deeper exploration prospects. The poor quality and low resolution of vintage seismic data has also impeded reservoir characterisation and sub-surface modelling. These sub-surface uncertainties, together with the large planned expenditure associated with forthcoming development, justified the need for the Demeter leading edge 3D seismic acquisition and processing techniques to underpin field development planning and reserves evaluations.The objective of the Demeter 3D survey was to re-image the NWSV area with a single acquisition and processing sequence to reduce multiple contamination and improve imaging of intra-reservoir architecture. Single source (133 nominal fold), shallow solid streamer acquisition combined with five stages of demultiple and detailed velocity analysis are considered key components of Demeter.The final Demeter volumes were delivered early 2005 and already some benefits of the higher resolution data have been realised, exemplified in the following:Successful drilling of development wells on the Wanaea, Lambert and Hermes oil fields and identification of further opportunities on Wanaea-Cossack and Lambert- Hermes;Dramatic improvements in seismic data quality observed at the giant Perseus gas field helping define seven development well locations;Considerably improved definition of fluvial channel architecture in the south of the Goodwyn gas field allowing for improved well placement and understanding of reservoir distribution;Identification of new exploration prospects and reevaluation of the existing prospect portfolio. Although the Demeter data set has given significant bandwidth needed for this revitalised phase of exploration and development, there remain areas that still suffer from poor seismic imaging, providing challenges for the future application of new technologies.

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Prospectivity insights from automated pre-interpretation processing of open-file 3D seismic data: characterising the Late Triassic Mungaroo Formation of the Carnarvon Basin, North West Shelf of Australia

The APPEA Journal ◽

10.1071/aj14002 ◽

2015 ◽

Vol 55 (1) ◽

pp. 15 ◽

Cited By ~ 1

Author(s):

Cliff C. Ford ◽

James K. Dirstein ◽

Alistair John Stanley

Keyword(s):

Spatial Databases ◽

Late Triassic ◽

Data Sets ◽

3D Seismic ◽

Gas Reservoirs ◽

Waveform Data ◽

Open File ◽

North West ◽

The North ◽

Carnarvon Basin

Waveform data from pre-interpretation processing is used in nine Late Triassic interpretation case studies from an area extending more than 30,000 km2 across the Exmouth Plateau, Kangaroo Trough and Rankin Trend on the North West Shelf of Australia. Events selected from a database of automatically generated surfaces extracted from six large open-file 3D marine surveys (~16,000 km2) are used to analyse reservoirs, seals, and pore fluid within the Brigadier and Mungaroo formations in this peer-reviewed paper. Today, geoscience teams are challenged with vast data sets such as the archived versions of more than 125 Carnarvon Basin 3D seismic surveys. Pre-interpretation processing delivers a database of numerous seismic events that cannot be effectively managed using traditional interpretation workstations. With, however, a 3D viewer to query, edit and merge the results, geoscience teams are able to review many large surveys and the surfaces in their interpretation workflows. At the 2013 WABS Conference in Perth, WA, two papers offered models for the Late Triassic gas reservoirs. These models represent many years of synthesis and integration of data by teams of geoscientists from two of the major operators on the North West Shelf. Validation and corroboration of the proposed models was gained by using selected pre-interpretation surfaces. Stacking patterns, waveform fitness, amplitude and two-way time surfaces from these spatial databases revealed geological insights about the formations, such as their complexity of structure, extent of reservoirs, and continuity of seals, along with a better understanding about the trapping and charge systems of the fields.

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IMPACT OF 3D SEISMIC ON EXPLORATION AND DRILLING SUCCESS IN THE DAMPIER SUB-BASIN, WA

The APPEA Journal ◽

10.1071/aj98006 ◽

1999 ◽

Vol 39 (1) ◽

pp. 87

Author(s):

D.R. Kingsley ◽

L.A. Tilbury

Keyword(s):

Success Rate ◽

3D Seismic ◽

3D Technology ◽

Spatial Continuity ◽

North West ◽

Associated Production ◽

The North ◽

3D Data ◽

Stratigraphic Reservoir ◽

Structural Definition

Application of 3D technology and the strategy of acquiring 'wall-to-wall' 3D data over WA-28-P and the associated production licences has had a major impact on the exploration and appraisal success of the North West Shelf Venture.The different aspects of 3D technology have contributed to this success to varying degrees according to the geological setting of the prospects and fields. In general, all have benefited from improved structural definition, better stratigraphic/reservoir definition, improved depth conversion and the spatial continuity of data inherent in 3D datasets.Noteable discoveries attributable to 3D technology include North Rankin West (NRA–22), Perseus–1 (and appraisals Perseus–2, –3A, Perseus South–1), Capella–1, Sculptor–1, Hermes (Lambert–2), Keast–1, Dockrell–2, and appraisal wells Yodel–2, Egret–2 and Lambert–4. Despite this outstanding success, several noteable dry wells, including West Dixon–1 (Triassic), Spica–1, Malmsey–1 and Wanaea–5 (appraisal), have been drilled.The continuing application of 3D technology, although in an increasingly mature area where more subtle and higher risk traps will be the norm, is expected to maintain a high success rate for the North West Shelf Venture.

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Stress-induced seismic azimuthal anisotropy, sand-shale content, and depth trends offshore North West Australia

Geophysics ◽

10.1190/geo2015-0709.1 ◽

2017 ◽

Vol 82 (2) ◽

pp. C77-C90 ◽

Cited By ~ 1

Author(s):

Lisa J. Gavin ◽

David Lumley

Keyword(s):

Confining Pressure ◽

Horizontal Stress ◽

Azimuthal Anisotropy ◽

P Wave ◽

Model Parameters ◽

Burial Depth ◽

3D Seismic ◽

Depth Limit ◽

North West ◽

S Waves

Seismic azimuthal anisotropy is apparent when P-wave velocities vary with source-receiver azimuth and downward-propagating S-waves split into two quasi-S-waves, polarized in orthogonal directions. Not accounting for these effects can degrade seismic image quality and result in erroneous amplitude analysis and geologic interpretations. There are currently no physical models available to describe how azimuthal anisotropy induced by differential horizontal stress varies with sand-shale lithology and depth; we develop a model that does so, in unconsolidated sand-shale sequences offshore North West Australia. Our method naturally introduces two new concepts: “critical anisotropy” and “anisotropic depth limit.” Critical anisotropy is the maximum amount of azimuthal anisotropy expected to be observed at the shallowest sediment burial depth, where the confining pressure and sediment compaction are minimal. The anisotropic depth limit is the maximum depth where the stress-induced azimuthal anisotropy is expected to be observable, where the increasing effects of confining pressure, compaction, and cementation make the sediments insensitive to differential horizontal stress. We test our model on borehole log data acquired in the Stybarrow Field, offshore North West Australia, where significant differential horizontal stress and azimuthal anisotropy are present. We determine our model parameters by performing regressions using dipole shear log velocities, gamma-ray shale volume logs, and depth trend data. We perform a blind test using the model parameters derived from one well to accurately predict the azimuthal anisotropy values at two other wells in an adjacent area. We use our anisotropy predictions to improve the well-tie match of the modeled angle-dependent reflectivity amplitudes to the 3D seismic amplitude variation with offset data observed at the well locations. Future applications of our method may allow the possibility to estimate the sand-shale content over a wide exploration area using anisotropic parameters derived from surface 3D seismic data.

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Recent Submarine Landslides on the Continental Slope of Storfjorden and Kveithola Trough-Mouth Fans (North West Barents Sea)

Submarine Mass Movements and Their Consequences ◽

10.1007/978-94-007-2162-3_65 ◽

2011 ◽

pp. 735-745 ◽

Cited By ~ 11

Author(s):

Renata G. Lucchi ◽

Maria T. Pedrosa ◽

Angelo Camerlenghi ◽

Roger Urgeles ◽

Ben De Mol ◽

...

Keyword(s):

Continental Slope ◽

Barents Sea ◽

Submarine Landslides ◽

North West ◽

Trough Mouth Fans

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The Western Australia Modeling project — Part 1: Geomodel building

Interpretation ◽

10.1190/int-2018-0217.1 ◽

2019 ◽

Vol 7 (4) ◽

pp. T773-T791 ◽

Cited By ~ 1

Author(s):

Jeffrey Shragge ◽

Julien Bourget ◽

David Lumley ◽

Jeremie Giraud ◽

Thomas Wilson ◽

...

Keyword(s):

Western Australia ◽

Seismic Data ◽

Large Scale ◽

Viscoelastic Model ◽

Companion Paper ◽

3D Seismic ◽

Seismic Modeling ◽

North West ◽

Northern Carnarvon Basin ◽

And Migration

A key goal in industry and academic seismic research is overcoming long-standing imaging, inversion, and interpretation challenges. One way to address these challenges is to develop a realistic 3D geomodel constrained by local-to-regional geologic, petrophysical, and seismic data. Such a geomodel can serve as a benchmark for numerical experiments that help users to better understand the key factors underlying — and devise novel solutions to — these exploration and development challenges. We have developed a two-part case study on the Western Australia (WA) Modeling (WAMo) project, which discusses the development and validation of a detailed large-scale geomodel of part of the Northern Carnarvon Basin (NCB) located on WA’s North West Shelf. Based on the existing regional geologic, petrophysical, and 3D seismic data, we (1) develop the 3D geomodel’s tectonostratigraphic surfaces, (2) populate the intervening volumes with representative geologic facies, lithologies, and layering as well as complex modular 3D geobodies, and (3) generate petrophysical realizations that are well-matched to borehole observations point-wise and in terms of vertical and lateral trends. The resulting 3D WAMo geomodel is geologically and petrophysically realistic, representative of short- and long-wavefield features commonly observed in the NCB, and leads to an upscaled viscoelastic model well-suited for high-resolution 3D seismic modeling studies. In the companion paper, we study WAMo seismic modeling results that demonstrate the quality of the WAMo geomodel for generating shot gathers and migration images that are highly realistic and directly comparable with those observed in NCB field data.

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3D Seismic classification of Fluid Escape Pipes in the western Exmouth Plateau, North West Shelf of Australia (A)

Journal of the Geological Society ◽

10.1144/jgs2020-096 ◽

2020 ◽

pp. jgs2020-096

Author(s):

Susy Mercado Ruge ◽

Nicola Scarselli ◽

Awad Bilal

Keyword(s):

Fluid Flow ◽

Significant Risk ◽

Sedimentary Basins ◽

Upper Jurassic ◽

Seismic Survey ◽

3D Seismic ◽

Seismic Reflection Data ◽

North West ◽

Exmouth Plateau ◽

Northern Carnarvon Basin

Fluid escape pipes are vertical pathways of focused flow venting from a variety of deep overpressure sources. These geological features are typical of many sedimentary basins, including proven petroliferous provinces worldwide, such as the North Sea and the Exmouth Plateau in the Northern Carnarvon Basin, Northwest Australia. High quality three-dimensional (3D) seismic reflection data from the western Exmouth Plateau revealed the occurrence of exceptionally well-imaged fluid escape pipes affecting the Jurassic strata and the Triassic Mungaroo Formation, a key reservoir unit in the basin. A total of 171 fluid escape pipes, including blowout, seepage and hydrothermal pipes, were mapped, and their geomorphic characteristics were analysed. In the study area, these features form prominent vertical columns up to 4.5 km long disrupting continuous reflections of the Triassic to Jurassic section. Numerous fluid escape pipes terminate with paleo-pockmarks affecting at the Upper Jurassic syn-extension strata, providing evidence for pipe genesis during the early stages of the Late Jurassic rifting in the Exmouth Plateau . Fluid escape pipes were found rooting from different stratigraphic levels, suggesting multiple fluid sources within the Triassic sediments. Several fluid flow structures nucleated along or nearby rift-related fault planes within the Mungaroo Formation providing further evidence of rifting as a main triggering factor of important fluid flow in the basin.In the study area, the presence of fluid escape pipes represents a significant risk for the preservation of potential hydrocarbons accumulations as when these features form, vertical fluid venting breaches through stratigraphy compromising the integrity of seal units. This seems supported by the lack of significant discoveries within the area covered by seismic survey analysed in this research.

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APLIKASI METODE PSEUDO 3D SEISMIK DI CEKUNGAN JAWA BARAT UTARA MENGGUNAKAN K.R. BARUNA JAYA II

Oseanika ◽

10.29122/oseanika.v1i2.4562 ◽

2021 ◽

Vol 1 (2) ◽

pp. 1-12

Author(s):

Trevi Jayanti Puspasari ◽

Sumirah Sumirah

Keyword(s):

Data Processing ◽

Seismic Data ◽

Oil And Gas ◽

Oil And Gas Industry ◽

Processing Technique ◽

3D Seismic ◽

Seismic Data Processing ◽

West Java ◽

Gas Industry ◽

North West

ABSTRAK Tuntutan untuk mengikuti perkembangan kebutuhan industri migas menjadi motivasi dalam mengembangkan teknik penerapan dan aplikasi akuisisi seismik multichannel 2D. Perkembangan kebutuhan eksplorasi industri migas tidak diimbangi dengan anggaran peningkatan alat survei seismik milik negara termasuk yang terpasang di K.R. Baruna Jaya II – BPPT. Penerapan metode pseudo 3D pada disain survei dan pengolahan data dapat menjadi solusi efektif dan efisien dalam mengatasi persoalan tersebut. Metode Pseudo 3D merupakan suatu teknik akuisisi dan pengolahan data dengan menitik beratkan pada disain akuisisi dan inovasi pengolahan data seismik 2D menghasilkan penampang keruangan (3D) berdasarkan input data seismik yang hanya 2D. Penelitian ini bertujuan untuk mengaplikasikan metode pseudo 3D seismik di Cekungan Jawa Barat Utara menggunakan wahana KR. Baruna Jaya II yang dilakukan pada Desember 2009. Sebagai hasil, pengolahan data 2D lanjutan telah dilakukan dan diperoleh profil penampang seismik keruangan (3D). Profil hasil pengolahan data Pseudo 3D ini dapat menjadi acuan dalam pengambilan keputusan dan rencana survei berikutnya. Kata Kunci: Seismik Pseudo 3D, Seismik multichannel 2D, K.R. Baruna Jaya II, Cekungan Jawa Barat Utara. ABSTRACT [Aplication of Seismic Pseudo 3D in Nort West Java Basin Using K.R. Baruna Jaya II] The demand to follow the growth of needs in the oil and gas industry is a motivation in the developing of techniques for assessment and applying 2D multichannel seismic acquisition. The development of exploration needs for the oil and gas industry is not matched by budget for an upgrade Government’s seismic equipment including equipment installed in K.R. Baruna Jaya II. Applied Pseudo 3D method in survey and seismic data processing can be an effective and efficient solution. The pseudo 3D method is a data acquisition and processing technique with an emphasis on the acquisition design and 2D seismic data processing innovation to produce a 3D seismic volume. This study aims to apply the pseudo 3D seismic method in the North West Java Basin using the K.R. Baruna Jaya II which was held in Desember 2009. As a Result, advanced seismic processing was carried out to output a seismic volume (3D) profile. This profile can be used as a reference in making decisions and planning the next survey. Keywords: Pseudo 3D Seismic, Seismic 2D multichannel, K.R. Baruna Jaya II, Nort West Java Basin.

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SEISMIC DELINEATION OF STRUCTURE-CONTROLLED CARBONATE CEMENT AND POTENTIAL ECONOMIC IMPLICATIONS, ANGEL FIELD, NORTH WEST SHELF

The APPEA Journal ◽

10.1071/aj94017 ◽

1995 ◽

Vol 35 (1) ◽

pp. 280

Author(s):

S. Ryan-Grigor ◽

J.P. Schulz-Rojahn

Keyword(s):

Seismic Data ◽

High Amplitude ◽

Fault System ◽

3D Seismic ◽

Economic Implications ◽

Northern Margin ◽

North West ◽

The North ◽

Migration Pathways ◽

3D Seismic Data

Major carbonate-cemented zones occur in Late Jurassic Angel Formation sandstones of marine mass flow origin that contain large hydrocarbon reserves in the Angel Field, Dampier Sub-basin. Preliminary results suggest that poikilotopic dolomite cement is dominant. The carbonate-cemented zones are identifiable from wireline log response and 3D seismic data, and occur in discrete intervals with a cumulative thickness of approximately 165m at Angel-2. These intervals produce a zone of high amplitude reflections of about 100 ms two-way time. Field-wide seismic mapping indicates that these carbonate-cemented zones sharply abut the northern margin of a major east-west trending strike-slip fault system that traverses this field. The carbonate-cemented zones extend in a wedge-like shape towards the northeast and concentrate along the crest of the main structural trend.The results underscore the importance of 3D seismic data for a better estimation of reservoir risk and reserves in variably carbonate-cemented sandstones.The carbonate-cemented zones may represent a 'plume' related to migration of petroleum and/or carbon dioxide. Therefore delineation of major carbonate-cemented zones using seismic data may aid in the identification of petroleum migration pathways and pools in the North West Shelf. Alternatively, carbonate cements dissolved south of the major fault zone and possibly in downdip locations in which case dissolution pores may exist in these areas. Further research is required to evaluate these hypotheses.

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