OIL AND GAS PROSPECTS OF THE GELTWOOD BEACH ANTICLINE, MILLICENT, SOUTH AUSTRALIA

1963 ◽  
Vol 3 (1) ◽  
pp. 69
Author(s):  
R. C. SPRIGG ◽  
J. B. WOOLLEY

The Geltwood Beach (buried) anticline is located near the ocean coast in south-east South Australia, directly west of the agricultural and industrial town of Millicent. The structure is developed in Mesozoic to Tertiary sediments forming the inner part of the continental sedimentary terrace which in this situation coincides also with the Nelson "half-graben".The Geltwood Beach anticline is more than five miles long by two or more miles wide. It is part of a still larger regional development which pitches south-east into the deeper known portions of the Gambier-Otway Cretaceous to Tertiary Basin. There is no surface expression to the structure.Structural "closure" on the base of the Tertiary may not exceed 100 feet, but an extensive area of structural flattening along the crest of the anticline (defined by structural drilling and geophysical techniques) overlies a zone of extensive sedimentary wedge-out within the predicted and prospective cretaceous sediments in depth. The wedging is predicted to be in the nature of progressive overlap onto structural "nosing" or alternatively, buried-ridge development in presumed Otway Group sediments in depth.A thickness of 5,000 to 8,000 feet of unconsolidated Upper Cretaceous to Tertiary sediments, wedging to the north-west along the crest of the anticline in the deeper developments is expected to include the prospective Belfast Mudstone equivalents and related beds of the Port Campbell (Victoria) Association.The Geltwood Beach structure lies approximately half way between the Mt. Salt No. 1 and Beachport No. 1 wells. In the distance of 45 miles between the latter wells, the dominantly Cretaceous (post-Otway) sedimentary section wedges spectacularly from 7,000 feet (possibly considerably more) to no more than 100 feet. The available geophysical evidence suggests that most of this wedging occurs within the zone of the Geltwood Beach anticline. For this reason, the anticline is believed to be well located for the development of structural and stratigraphic traps in a marginal continental shelf environment of proven thick sedimentation.In the Mt. Salt No. 1 well, clays and shales encountered at at least five stratigraphic levels within the Lower Tertiary to Middle Cretaceous section provided adequate capping to underlying highly porous and permeable reservoir sands, the lowermost of which were brine-bearing.Geltwood Beach is a locale of preferred coastal bitumen stranding. The weight of published evidence now points to nearby submarine seepage within the reach of erosive storm waves: recorded earthquakes in this vicinity are known to have greatly affected the activity of these seepages.The conclusion is reached that the Geltwood Beach anticline is favourably situated up-dip on the inner continental shelf margin to accumulate hydrocarbons in potentially commercial quantities. The structure lies south of the Beachport-Kalangadoo "hinge-line" of the Nelson half-graben in a zone of submarine oil seepage. A proposed deep test well to be located near the culmination of shallower structure is expected to provide a satisfactory test in respect to both structural and (to a lesser extent) deeper stratigraphic entrapment of petroleum.

2002 ◽  
Vol 8 (2-3) ◽  
pp. 206-208
Author(s):  
V.G. Osadchyi ◽  
◽  
O.A. Prykhod'ko ◽  
I.I. Hrytsyk ◽  
◽  
...  

2021 ◽  
Vol 40 (3) ◽  
pp. 172-177
Author(s):  
Jarrad Grahame ◽  
Victoria Cole

The North West Shelf (NWS) of Australia is a prolific hydrocarbon province hosting significant volumes of hydrocarbons, primarily derived from Jurassic and Cretaceous targets. A new regional, integrated geoscience study has been undertaken to develop insights into the paleogeography and petroleum systems of Late Permian to Triassic successions, which have been underexplored historically in favor of Jurassic to Cretaceous targets. Within the NWS study area, graben and half-graben depocenters developed in response to intracratonic rifting that preceded later fragmentation and northward rifting of small continental blocks. This, coupled with contemporaneous cycles of rising sea levels, brought about the development of large embayments and shallow, epeiric seas between the Australian continental landmass and outlying continental fragments in the early stages of divergence. Key elements of the study results discussed herein include the study methodology, the paleogeographic and gross depositional environment mapping, and the reservoir and source kitchen modeling. The study results highlight the presence of depocenters that developed within oblique rift zones due to regional Permo-Triassic strike-slip tectonics that bear compelling similarities to modern-day analogues. These intracratonic rift zones are well-known and prominent tectonic features resulting from mantle upwelling and weakening of overlying lithospheric crust, initiating the development of divergent intraplate depocenters. The comprehensive analysis of these depocenters from a paleogeographic and petroleum system perspective provides a basin evaluation tool for Triassic prospectivity.


2019 ◽  
Vol 7 (4) ◽  
pp. SH19-SH31
Author(s):  
Gabriela Salomão Martins ◽  
Webster Ueipass Mohriak ◽  
Nivaldo Destro

The Sergipe-Alagoas Basin, situated in the north-east Brazilian margin, has a long tradition of oil and gas production and the presence and distribution of evaporites play an important role in petroleum systems in the basin. However, little research has focused on the structural evolution of the older, synrift evaporitic sections of the basin. We have focused explicitly in the detailed subsurface structural characterization of the rift in the Alagoas subbasin and the distribution of the Early Aptian evaporites. To accomplish this objective, we interpreted selected 2D and 3D seismic and well data located in two areas known as the Varela Low (VL) and Fazenda Guindaste Low (FGL). We identified diverse deformation styles in those two basin depocenters. Our interpretation indicates that VL consists of a half-graben with a significant rollover structure, controlled by two listric northeast–southwest border faults. The deformation in the hanging wall is also accommodated by release faults and minor antithetic faults. In this depocenter, we mapped in the seismic and the well data an older evaporitic sequence within the Coqueiro Seco Fm., known as Horizonte Salt. This evaporitic section occurs in the internal part of the VL half graben, where it is limited by release and antithetic faults. Significant salt strata growing toward the antithetic fault is observed. Whereas, the FGL represents a graben elongated along the north-east direction and is controlled by several types of structures. We recognized normal synthetic and antithetic faults, transfer zones, release faults, and rollover anticlines in the seismic throughout this depocenter. We mapped an evaporitic section within the Maceió Fm., known as Paripueira Salt, which consists of disconnected salt bodies, restricted to the hanging walls of synrift faults.


2007 ◽  
Vol 65 (1-4) ◽  
pp. 417-429 ◽  
Author(s):  
John R. Siddorn ◽  
J. Icarus Allen ◽  
Jerry C. Blackford ◽  
Francis J. Gilbert ◽  
Jason T. Holt ◽  
...  

2001 ◽  
Vol 41 (2) ◽  
pp. 80
Author(s):  
S.J. Smith

Last year the petroleum industry witnessed the enactment of new legislation both at Commonwealth and State levels. The principal legislative change to environmental management was the introduction of the Commonwealth Government’s Environmental Protection and Biodiversity Act, 2000 (EPBC Act). South Australia and Victoria also implemented new Petroleum Acts and/ or Regulations.Construction of the Eastern Gas Pipeline was also completed last year, whilst preliminary approvals and environmental assessment continues for the Papua New Guinea, Timor Sea and Tasmania Natural Gas pipelines. Offshore exploration continued, particularly in the North West Shelf, Otway Basin, Timor Sea and Bass Strait.Other critical areas of environmental management included greenhouse gases, national pollution inventory reporting and the increasing requirements for environmental approval and management under various state environmental legislation.This paper provides an overview of environmental developments in the petroleum industry during the year 2000, in particular, the implication of new legislation, new technology, e-commerce and a greater focus on environmental reporting.


2009 ◽  
Vol 49 (1) ◽  
pp. 465
Author(s):  
Thomas Bernecker

The Australian Government formally releases new offshore exploration areas at the annual APPEA conference. This year, 31 areas plus two special areas in five offshore basins are being released for work program bidding. Closing dates for bid submissions are either six or twelve months after the release date (i.e. 3 December 2009 and 29 April 2010), depending on the exploration status in these areas is and on data availability. The 2009 release areas are located in Commonwealth waters offshore Northern Territory, Western Australia, South Australia and Victoria, comprising intensively explored areas close to existing production as well as new frontiers. As usual, the North West Shelf features very prominently and is complimented by new areas along the southern margin, including frontier exploration areas in the Ceduna Sub-basin (Bight Basin) and the Otway Basin. The Bonaparte Basin is represented by one release area in the Malita Graben, while five areas are available in the Southern Browse Basin in an under-explored area of the basin. A total of 14 areas are being released in the Carnarvon Basin, with eight areas located in the Dampier Sub-basin, three small blocks in the Rankin Platform and three large blocks on the Northern Exmouth Plateau (these are considered a deep water frontier). In the south, six large areas are on offer in the Ceduna Sub-basin and five areas of varying sizes are being released in the Otway Basin, including a deep water frontier offshore Victoria. The special release areas are located in the Petrel Sub-basin, Bonaparte Basin offshore Northern Territory, and encompass the Turtle/Barnett oil discoveries. The 2009 offshore acreage release offers a wide variety of block sizes in shallow as well as deep water environments. Area selection has been undertaken in consultation with industry, the states and Territory. This year’s acreage release caters for the whole gamut of exploration companies given that many areas are close to existing infrastructure while others are located in frontier offshore regions. As part of Geoscience Australia’s Offshore Energy Security Program, new data has been acquired in offshore frontier regions and have yielded encouraging insights into the hydrocarbon prospectivity of the Ceduna-Sub-basin.


2018 ◽  
Vol 58 (2) ◽  
pp. 719
Author(s):  
Lourens Jacobs ◽  
Nancy Nguyen ◽  
Ryan Beccarelli

Woodside is an Australian oil and gas company and a leading global operator of offshore gas platforms and onshore LNG processing facilities. It is a public company listed on the Australian Securities Exchange headquartered in Perth, Western Australia. Woodside operates the Goodwyn A gas platform on behalf of the North West Shelf (NWS) Project. Woodside assessed Li-ion battery technology and considered the technology mature and ready to be utilised on offshore and onshore operating assets. Woodside operates dedicated islanded gas turbine power generation at each of its onshore and offshore facilities. It was concluded that a large battery energy storage solution (BESS) can deliver several advantages if connected to such an islanded power generation system. The most significant benefit materialises by using a BESS as backup (or spinning reserve) for the gas turbine generators (GTGs). Woodside decided to pioneer the Li-ion BESS technology in a first of its kind application on the NWS Project offshore Goodwyn A gas platform. The Goodwyn A BESS is designed for a 1 MW power and 1 MWh energy capacity, which is considered sufficient to provide the spinning reserve for the Goodwyn A platform. Currently, Goodwyn A operates four 3.2 MW GTGs to provide a typical load of 7–8 MW, with one GTG providing the N+1 spinning reserve. When the BESS is connected to the power generation system, Goodwyn A will operate three GTGs, with the BESS proving the backup in case one of the GTGs trip. The BESS will provide the full 1 MW for a minimum of 1 h, which will give the operators enough time to start the standby GTG or adjust the facility loads (load shedding). The result will be a decrease in overall fuel gas consumption (due to better efficiencies on the remaining GTGs in operation) and a related reduction in CO2 emissions. The project supports the overall objective of the North West Shelf Project to improve the energy intensity of its facilities by 5% by 2020. Woodside believes that developing capability and experience on the installation of BESSs, using Goodwyn A as an early adopter, will facilitate similar and larger installations on other Woodside operated offshore and onshore assets. This is one of the technologies Woodside believes will play an important role to ensure a lower carbon future globally.


2020 ◽  
Vol 60 (2) ◽  
pp. 588
Author(s):  
Meysam Banimahd ◽  
Steve Tyler ◽  
Matthew Kuo ◽  
Fiona Chow

The July 2019 magnitude 6.6 earthquake 200 km offshore from Broome is a recent reminder of the significant risk that earthquakes pose to oil and gas infrastructure in Australia. Unlike tropical cyclones, there are no reliable methods for predicting the timing, location and magnitude of imminent earthquakes. Appropriate risk management is therefore required, together with the implementation of emergency response and integrity management procedures, to manage the potential impacts to health, safety, process safety, the environment and production. Given the concentration of oil and gas infrastructure in the north west of Australia, a collaborative approach is advantageous for earthquake risk management and emergency response measures. This paper shares Woodside’s earthquake risk and integrity management procedures with the aim of enabling appropriate quality and consistency throughout the industry. The paper reviews state-of-the-art international practice in earthquake risk management for critical infrastructure from design to operation. Applicable seismic design criteria, likely failure modes and performance requirements are also described. Woodside’s real-time earthquake alert and integrity management systems are presented. Recommendations are made on best practice for earthquake risk management in the region and areas for further collaboration and improvement within the industry.


Sign in / Sign up

Export Citation Format

Share Document