Origin of basin-scale syn-extensional synclines on the southern margin of the Northern Carnarvon Basin, Western Australia

2018 ◽  
Vol 176 (1) ◽  
pp. 115-128 ◽  
Author(s):  
Sam McHarg ◽  
Chris Elders ◽  
Jane Cunneen
Keyword(s):  
Western Australia ◽  
Southern Margin ◽  
Basin Scale ◽  
Northern Carnarvon Basin ◽  
Carnarvon Basin

NEOCOMIAN EUSTATIC CHANGES — BIOSTRATIGRAPHIC EVIDENCE FROM THE CARNARVON BASIN

1979 ◽  
Vol 19 (1) ◽  
pp. 66 ◽  
Author(s):  
J.F. Wiseman
Keyword(s):  
Sea Level ◽  
Western Australia ◽  
Northern Carnarvon Basin ◽  
Carnarvon Basin

A fall in sea level of approximately 200m affected the northern Carnarvon Basin of Western Australia during the earliest Neocomian. This was followed by a brief lowstand and then a basin-wide flooding beginning in the Late Valanginian or Early Hauterivian. Maps showing the pattern of inundation as the sea level rose reflect the palaeotopography of the basin at the time. These maps are derived from the age of the base of the onlapping sequence, namely the Winning Group. The ages are based on a palynological zonation of the Neocomian to Early Aptian.

PETROLEUM IN WESTERN AUSTRALIA: A REVIEW OF EXPLORATION, PRODUCTION, AND FUTURE PROSPECTS

1975 ◽  
Vol 15 (2) ◽  
pp. 72
Author(s):  
Phillip E. Playford
Keyword(s):  
Western Australia ◽  
Gas Production ◽  
Oil Field ◽  
Petroleum Exploration ◽  
Oil Reserves ◽  
The North ◽  
Recent Success ◽  
Northern Carnarvon Basin ◽  
Exploration Activity ◽  
Carnarvon Basin

Modern petroleum exploration has been in progress in Western Australia since 1952, and has been concentrated mainly in the Perth, Carnarvon, Canning, and Bonaparte Gulf Basins. Two large onshore fields have been developed, the Barrow Island oilfield in the Carnarvon Basin (found in 1964), and the Dongara gasfield in the Perth Basin (found in 1966). Small gasfields have also been developed at Mondarra, Gingin, and Walyering in the Perth Basin, but Gingin and Walyering are now virtually depleted.Major gas-condensate fields have been found offshore. These are the North Rankin, Goodwyn, West Tryal Rocks, and Angel fields in the northern Carnarvon Basin, and the Scott Reef field in the Browse Basin. They were found during the period 1971 to 1973, but none has yet been developed.Since 1968 the accent has been on offshore exploration, and this reached a peak in 1972. Exploration activity, both onshore and offshore, is currently declining, owing to the lack of recent success and the unfavourable exploration climate prevailing in Australia today.Original reserves in the Dongara gasfield amounted to about 13 billion cubic metres, of which nearly 2.1 billion have now been produced. Current gas production from Dongara and the small adjoining Mondarra field is about 2.2 million cubic metres per day, and production will continue at about this rate until 1981, after which it will begin declining. Production will fall steeply in 1987, when existing contracts expire. At that time about 90% of the reserves will have been depleted.The original in-place reserves of the Barrow Island oil-field amounted to some 750 million barrels, and it is expected that about 240 million will be recovered. Current oil production is around 37,000 barrels per day, compared with the peak of 48.000 barrels per day reached in 1970. Nearly 43% of the original reserves have now been produced.Total reserves of the major fields in the offshore northern Car-narvon Basin (in the proved and probable categories) are more than 345 billion cubic metres of gas and 320 million barrels of condensate. Of these amounts more than 220 billion cubic metres of gas and 180 million barrels of condensate are in the North Rankin field, which is the largest gasfield in Australia and is a giant by world standards. This is followed by Goodwyn (about 65 billion cubic metres of gas and 90 million barrels of condensate), West Tryal Rocks (more than 30 billion cubic metres of gas) and Angel (about 30 billion cubic metres of gas and 50 million barrels of condensate).Further drilling will be required before gas reserves of the Scott Reef field can be estimated, but the results of the first well and the size of the structure indicate that they could be very large. It is clear that future exploration in Western Australia will be mainly concentrated offshore, in the Carnarvon, Browse, Bonaparte Gulf, and Perth Basins. However, there are still some prospective onshore areas in the Perth, Carnarvon, and Canning Basins.The chances of finding giant oilfields in Western Australia have declined markedly in recent years, as It seems that the generative sequences are mainly gas prone, and most of the obvious structures have now been drilled. However, the prospects are good for further large gas discoveries, and there is a reasonable chance that significant oil reserves will also be found.

Petroleum source rocks of Western Australia

2018 ◽  
Vol 58 (1) ◽  
pp. 282 ◽  
Author(s):  
K. Ameed R. Ghori
Keyword(s):  
Western Australia ◽  
Oil And Gas ◽  
Source Rocks ◽  
Lower Permian ◽  
Burial History ◽  
Canning Basin ◽  
Petroleum Systems ◽  
Northern Carnarvon Basin ◽  
Coal Measures ◽  
Carnarvon Basin

Petroleum geochemical analysis of samples from the Canning, Carnarvon, Officer and Perth basins identified several formations with source potential, the: • Triassic Locker Shale and Jurassic Dingo Claystone of the Northern Carnarvon Basin; • Permian Irwin River Coal Measures and Carynginia Formation, Triassic Kockatea Shale and Jurassic Cattamarra Coal Measures of the Perth Basin; • Ordovician Goldwyer and Bongabinni formations, Devonian Gogo Formation and Lower Carboniferous Laurel Formation of the Canning Basin; • Devonian Gneudna Formation of the Gascoyne Platform and the Lower Permian Wooramel and Byro groups of the Merlinleigh Sub-basin of the Southern Carnarvon Basin; and • Neoproterozoic Brown, Hussar, Kanpa and Steptoe formations of the Officer Basin. Burial history and geothermal basin modelling was undertaken using input parameters from geochemical analyses of rock samples, produced oil, organic petrology, apatite fission track analysis (AFTA), heat flows, subsurface temperatures and other exploration data compiled by the Geological Survey of Western Australia (GSWA). Of these basins, the Canning, Carnarvon, and Perth basins are currently producing oil and gas, whereas the Southern Carnarvon and Officer basins have no commercial petroleum discovery yet, but they do have source, reservoir, seal and petroleum shows indicating the presence of petroleum systems. The Carnarvon Basin contains the richest identified petroleum source rocks, followed by the Perth and Canning basins. Production in the Carnarvon Basin is predominantly gas and oil, the Perth Basin is gas-condensate and the Canning Basin is oil dominated, demonstrating the variations in source rock type and maturity across the state. GSWA is continuously adding new data to assess petroleum systems and prospectivity of these and other basins in Western Australia.

Depositional settings and palynofacies assemblages of the Upper Triassic fluvio-deltaic Mungaroo Formation, northern Carnarvon Basin, Western Australia

2020 ◽  
Vol 90 (4) ◽  
pp. 403-428
Author(s):  
Joe Scibiorski ◽  
Daniel Peyrot ◽  
Simon Lang ◽  
Tobias H.D. Payenberg ◽  
Adam Charles
Keyword(s):  
Western Australia ◽  
Lower Energy ◽  
High Energy ◽  
Upper Triassic ◽  
Floodplain Lakes ◽  
Northern Carnarvon Basin ◽  
Active Channels ◽  
Organic Particles ◽  
Abandoned Channels ◽  
Carnarvon Basin

ABSTRACT Palynofacies analysis was carried out on 92 core samples from the fluvio-deltaic Middle to Upper Triassic Mungaroo Formation, Northern Carnarvon Basin, Western Australia. The analyses demonstrate that each depositional environment (“depofacies”) sampled has a characteristic palynofacies assemblage reflecting the varied origins, transport, sorting, and preservation histories of organic particles in sediments. The sampling covered a wide range of depofacies identified in fluvial channel, floodplain, crevasse splay, distributary channel, and tidal zone paleoenvironments and included laminated to massive mudstones and siltstones, cross-bedded sandstones, immature pedogenically altered paleosols, and coals. Although each depofacies has a characteristic palynofacies association, there is a high degree of variability within and overlap between preparations. Black-opaque particles were the dominant component in active fluvial, crevasse, and distributary channels. In contrast, palynomorphs, brown wood particles, and cuticle were more common in abandoned channels, floodplain lakes, and other lower-energy environments. The composition of palynomorphs also varies greatly between depofacies due to factors including the bioproductivity of the surrounding vegetation source area, water-table levels, preservation potential, and the fluid dynamic properties of organic particles. The depofacies were grouped into five “process regimes” (active channels, abandoned channels, lakes and periodically flooded areas, paleosols and swamps, tidal mudflats) based on their dominant depositional process. Depofacies in the same process regime tended to have similar palynofacies associations. Active channels yielded similar assemblages irrespective of whether they were fluvial, crevasse, or distributary channels because their dominant characteristic is high flow energy, which encourages the bypass of finer-grained particles, enhances the mechanical degradation of plant debris, and may inhibit local vegetation growth. Organic particles found in lower-energy environments (e.g., floodplain lakes) are on average larger, more elongate, and better preserved than particles found in high-energy environments (e.g., active channels). Although this study was restricted to samples from the upper Samaropollenites speciosus and lower Minutosaccus crenulatus biostratigraphic zones in a geographically limited area, its results are not influenced by the specific taxonomic composition of the vegetation but by the physiographic structure of surrounding plant communities; this suggests that palynofacies analysis could be used to distinguish depositional environments in deltaic settings from other stratigraphic intervals.

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