RIVOLI-1 GAS DISCOVERY — EXMOUTH SUB-BASIN, WESTERN AUSTRALIA

Offshore exploration in the Exmouth Gulf commenced with seismic surveys during the early 1960s and resulted in the first well Bundegi-1 being drilled in 1978. This well, situated on the Rivoli-Bundegi Trend, encountered an interpreted residual hydrocarbon zone in the Birdrong Sandstone, an 18 m untested hydrocarbon zone in the Learmonth Formation, and tight, possibly gas bearing sandstones in the Mungaroo Formation.Modern shallow-water marine seismic data acquired by the EP 325 Joint Venture during surveys in 1987 and 1988 allowed accurate mapping of the basal Cretaceous section and the distribution of the Birdrong Sandstone. Complex structuring in the Jurassic and Triassic section was also resolved with the modern data.The Rivoli gas discovery, approximately 4.5 km northeast of Bundegi-1, was made in August 1989, with the intersection of a 10.5 m hydrocarbon column consisting mainly of gas but with a very thin oil leg (0.2 m). The Birdrong Sandstone reservoir comprises 10 m of fluvial sandstones overlain by 7 m of marginal marine sandstones and provides an important calibration point for depositional environments in this unit. The Rivoli gas pool occurs in a simple, downthrown anticline sealed by Winning Group shales. Geochemical analysis of oil extracted from core, suggests an earlier charge of 'Rough Range-type' oil, possibly generated from pre-Jurassic source rocks.Several prospects and a variety of play types are recognised and considerable exploration potential remains to be tested along the Rivoli-Bundegi Trend.

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Deep learning for low-frequency extrapolation from multioffset seismic data

Geophysics ◽

10.1190/geo2018-0884.1 ◽

2019 ◽

Vol 84 (6) ◽

pp. R989-R1001 ◽

Cited By ~ 19

Author(s):

Oleg Ovcharenko ◽

Vladimir Kazei ◽

Mahesh Kalita ◽

Daniel Peter ◽

Tariq Alkhalifah

Keyword(s):

Deep Learning ◽

Seismic Data ◽

Signal To Noise Ratio ◽

Waveform Inversion ◽

Low Frequency ◽

Low Frequencies ◽

Seismic Surveys ◽

Full Waveform ◽

Frequency Components ◽

Marine Seismic

Low-frequency seismic data are crucial for convergence of full-waveform inversion (FWI) to reliable subsurface properties. However, it is challenging to acquire field data with an appropriate signal-to-noise ratio in the low-frequency part of the spectrum. We have extrapolated low-frequency data from the respective higher frequency components of the seismic wavefield by using deep learning. Through wavenumber analysis, we find that extrapolation per shot gather has broader applicability than per-trace extrapolation. We numerically simulate marine seismic surveys for random subsurface models and train a deep convolutional neural network to derive a mapping between high and low frequencies. The trained network is then tested on sections from the BP and SEAM Phase I benchmark models. Our results indicate that we are able to recover 0.25 Hz data from the 2 to 4.5 Hz frequencies. We also determine that the extrapolated data are accurate enough for FWI application.

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RECENT DISCOVERIES IN THE PYRENEES MEMBER, EXMOUTH SUB-BASIN: A NEW OIL PLAY FAIRWAY

The APPEA Journal ◽

10.1071/aj04021 ◽

2005 ◽

Vol 45 (1) ◽

pp. 233 ◽

Cited By ~ 3

Author(s):

J.P. Scibiorski ◽

M. Micenko ◽

D. Lockhart

Keyword(s):

Seismic Data ◽

Joint Venture ◽

Depositional Environments ◽

3D Seismic ◽

High Quality ◽

Gas Field ◽

Geological Information ◽

Key Factor ◽

Complex Structural ◽

3D Seismic Data

Recent drilling by BHP Billiton Pty Ltd in WA-155-P(1) and WA-12-R, on behalf of its partners Apache Energy Ltd and INPEX ALPHA LTD, has resulted in the discovery of four oil fields in the southern Exmouth Sub-basin, namely Ravensworth, Crosby, Stickle and Harrison. These discoveries, together with the earlier discoveries made by West Muiron–5 and Pyrenees–2, define the Early Cretaceous Pyrenees Member play fairway.The Pyrenees Trend play was first conceived in 1999 following appraisal of the Macedon gas field (Keall, 1999), but the concept remained dormant until the integration of geological information with high quality 3D seismic data led to the recognition of hydrocarbon related seismic attributes in the postulated play fairway.Ravensworth–1 intersected a 37 m gross oil column below a 7 m gas cap in high quality Pyrenees Member sandstones beneath the regionally significant Intra- Hauterivian Unconformity. Ravensworth, located on a northeast–southwest trending fault terrace, is a complex structural-stratigraphic trap that relies on separate top, base and cross-fault seals. High quality 3D seismic data coupled with recent interpretation techniques were integral to its discovery. In particular, the quantitative interpretation of seismic amplitude populations was a key factor in decreasing exploration risk.The Ravensworth discovery was followed by successful exploration wells on the adjacent Crosby, Stickle and Harrison fault terraces. Four appraisal wells have since been drilled at the northern ends of the main discoveries.The oil in the Pyrenees Member discoveries is biodegraded, moderately viscous (8–11 cp) and heavy (18–19° API gravity). Methane-dominated gas caps were intersected in Ravensworth–1, West Muiron–5 and Pyrenees–2.The recent drilling and coring campaigns by BHP Billiton and others in the Exmouth Sub-basin have significantly advanced knowledge of the stratigraphy and depositional environments of the late Tithonian to early Berriasian Macedon, Muiron and Pyrenees Members of the lower Barrow Group. The lower Barrow Group is a third order sequence deposited rapidly in marine to fluviodeltaic environments in response to the breakup of Gondwana and the onset of active rifting along the West Australian margin.BHP Billiton and its joint venture partners are assessing the commercial viability of the Pyrenees Trend discoveries.

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TROBRIAND BASIN EXPLORATION, PAPUA NEW GUINEA

The APPEA Journal ◽

10.1071/aj75008 ◽

1976 ◽

Vol 16 (1) ◽

pp. 81 ◽

Cited By ~ 2

Author(s):

K.T. Tjhin

Keyword(s):

Seismic Data ◽

Regional Studies ◽

Aeromagnetic Survey ◽

Tectonic Plates ◽

Seismic Surveys ◽

Irian Jaya ◽

Petroleum Generation ◽

Exploratory Wells ◽

Marine Seismic ◽

East West

Regional studies suggested that the Solomon Sea would be underlain by upper Tertiary sediments inluding possible Miocene reef carbonates similar to those found in the Gulf of Papua and Irian Jaya. As the Trobriand area of the Solomon Sea lies in a zone of interaction between the Australian and Pacific tectonic plates, it was considered likely that Tertiary basins prospective for petroleum would be present. In 1969 the East Papua aeromagnetic survey revealed a magnetic low which was interpreted as a basin, here named the Trobriand Basin. A sedimentary section of some 3000 m, situated under shallow water was indicated.Amoco, Australian Oil & Gas and Southern Pacific Petroleum made application for and were granted exploration permit PNG/15P in June, 1971. The Group initially undertook field geological, aerial photographic and hydrographic surveys which revealed the presence of numerous Pliocene to Recent coral reefs throughout the permit and also indicated the likely nature of economic basement. Between April 1972 and May 1973, three marine seismic surveys by Western Geophysical produced 2250 km of reflection profiles. The seismic data suggest that the Trobriand Basin is an east-west trending graben filled with up to 5000 m of probable Miocene and younger sediments. Positive structures, of which several were interpreted as mid-Miocene reefs, were mapped.Two subsidised exploratory wells, Goodenough No. 1 and Nubiam No. 1, were drilled in 1973. Only minor and questionable hydrocarbon shows were encountered and both wells bottomed in Miocene volcaniclastics. The wells penetrated immature upper Tertiary sediments with low present and palaeo-geothermal gradients and consequently the sediments might be considered an unfavourable environment for petroleum generation. Nevertheless, the Trobriand Basin has not been adequately explored for hydrocarbon accumulations as only a portion of the Tertiary section has been evaluated in two widely-spaced wells.

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STRATIGRAPHY AND PETROLEUM POTENTIAL OF THE ONSHORE CARPENTARIA BASIN, QUEENSLAND

The APPEA Journal ◽

10.1071/aj89009 ◽

1990 ◽

Vol 30 (1) ◽

pp. 149

Author(s):

B.A. McConachie ◽

J. Filatoff ◽

N. Senapati

Keyword(s):

Seismic Data ◽

Joint Venture ◽

Drill Hole ◽

Depositional Environments ◽

Petroleum Exploration ◽

Petroleum Reservoir ◽

Petroleum Potential ◽

Reflection Seismic ◽

The Past ◽

Sedimentary Fill

Over the past four years Comalco in joint venture with Bridge Oil have undertaken extensive exploration within the Carpentaria Basin. Over 3000 km of multifold reflection seismic data has been acquired and four petroleum exploration wells were drilled. In addition, the Queensland Department of Mines (GSQ) has drilled four cored full-section stratigraphic wells in the deeper parts of the basin.Analysis of the work to date indicates that the basin is not as structurally simple as first thought. Four sub- basins are recognised based on the composition and timing of Mesozoic sedimentary fill. These are the Weipa, Western Gulf, Staaten and Boomarra sub-basins. The Boomarra Sub-basin contains a Middle Triassic red-bed sequence which is 250 m thick in drill hole GSQ Dobbyn- 1. Thick, Middle Jurassic-Lower Cretaceous, basal fluvial and marine sandstone sequences are restricted to the Weipa and Staaten sub-basins, where they are confined principally to the palaeotopographic valleys. The Western Gulf Sub-basin is believed to contain minimal basal Mesozoic sandstone.Although sedimentary depositional environments exhibit widespread continuity throughout the Carpentaria Basin, variations in lithology and provenance as well as diachronism can be demonstrated between the various sub-basins. Most notably the late Neocomian marine transgression began earlier at Weipa than in the southern sub-basins. A basin-wide stratigraphy has been developed from deep drill hole correlations and mapping of outcrop sections around the margin of the basin in the Olive River, Gregory Range and Melish Park areas thus enabling the petroleum reservoir character of the basin to be determined.

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Formation geological depth image according to refraction and reflection marine seismic data

Geofizicheskiy Zhurnal ◽

10.24028/gzh.0203-3100.v39i6.2017.116375 ◽

2017 ◽

Vol 39 (6) ◽

pp. 106-121

Author(s):

A. O. Verpahovskaya ◽

V. N. Pilipenko ◽

Е. V. Pylypenko

Keyword(s):

Seismic Data ◽

Depth Image ◽

Marine Seismic

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PROCESSING AND IMAGING OF MARINE SEISMIC DATA FROM THE JEQUITINHONHA BASIN (BAHIA, BRAZIL)

Brazilian Journal of Geophysics ◽

10.22564/rbgf.v33i3.743 ◽

2016 ◽

Vol 33 (3) ◽

Author(s):

Lourenildo W.B. Leite ◽

J. Mann ◽

Wildney W.S. Vieira

Keyword(s):

Seismic Data ◽

Sedimentary Basins ◽

Study Results ◽

Marine Seismic ◽

Present Case Study

ABSTRACT. The present case study results from a consistent processing and imaging of marine seismic data from a set collected over sedimentary basins of the East Brazilian Atlantic. Our general aim is... RESUMO. O presente artigo resulta de um processamento e imageamento consistentes de dados sísmicos marinhos de levantamento realizado em bacias sedimentares do Atlântico do Nordeste...

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SOUTH GEORGIA MICROCONTINENT: CURRENT TECTONIC SETTING FROM GPS AND MARINE SEISMIC DATA

10.1130/abs/2019am-331332 ◽

2019 ◽

Author(s):

Ian W.D. Dalziel ◽

◽

Robert Smalley ◽

Lawrence A. Lawver ◽

Demian Gomez ◽

...

Keyword(s):

Seismic Data ◽

Tectonic Setting ◽

South Georgia ◽

Marine Seismic

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A Machine Learning-Based Seismic Data Compression and Interpretation Using a Novel Shifted-Matrix Decomposition Algorithm

Applied Sciences ◽

10.3390/app11114874 ◽

2021 ◽

Vol 11 (11) ◽

pp. 4874

Author(s):

Milan Brankovic ◽

Eduardo Gildin ◽

Richard L. Gibson ◽

Mark E. Everett

Keyword(s):

Real Time ◽

Seismic Data ◽

Matrix Decomposition ◽

Original Data ◽

Velocity Estimation ◽

Singular Vectors ◽

Well Stimulation ◽

Marine Seismic ◽

Value Decomposition ◽

Seismic Data Compression

Seismic data provides integral information in geophysical exploration, for locating hydrocarbon rich areas as well as for fracture monitoring during well stimulation. Because of its high frequency acquisition rate and dense spatial sampling, distributed acoustic sensing (DAS) has seen increasing application in microseimic monitoring. Given large volumes of data to be analyzed in real-time and impractical memory and storage requirements, fast compression and accurate interpretation methods are necessary for real-time monitoring campaigns using DAS. In response to the developments in data acquisition, we have created shifted-matrix decomposition (SMD) to compress seismic data by storing it into pairs of singular vectors coupled with shift vectors. This is achieved by shifting the columns of a matrix of seismic data before applying singular value decomposition (SVD) to it to extract a pair of singular vectors. The purpose of SMD is data denoising as well as compression, as reconstructing seismic data from its compressed form creates a denoised version of the original data. By analyzing the data in its compressed form, we can also run signal detection and velocity estimation analysis. Therefore, the developed algorithm can simultaneously compress and denoise seismic data while also analyzing compressed data to estimate signal presence and wave velocities. To show its efficiency, we compare SMD to local SVD and structure-oriented SVD, which are similar SVD-based methods used only for denoising seismic data. While the development of SMD is motivated by the increasing use of DAS, SMD can be applied to any seismic data obtained from a large number of receivers. For example, here we present initial applications of SMD to readily available marine seismic data.

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