Palaeomagnetic data on weathered bedrock and apatite fission track thermochronology have been combined with depositional history to propose a framework for weathering deposition and erosion in the Northparkes mine area.

Regolith-landform map and explanatory notes in area of patchy Mesozoic cover over late Precambrian to Devonian bedrock. Includes description of regolith materials, map units, landscape and regolith evolution, and potential geochemical exploration sample media

Legacy product - no abstract available

Legacy product - no abstract available

The Browse Basin hosts considerable gas and condensate resources, including the Ichthys and Prelude fields that are being developed for liquefied natural gas (LNG) production. Oil discoveries are sub-economic. This multi-disciplinary study integrating sequence stratigraphy, palaeogeography and geochemical data has mapped the spatial and temporal distribution of Jurassic to earliest Cretaceous source rocks. This study allows a better understanding of the source rocks contribution to the known hydrocarbon accumulations and charge history in the basin, including in underexplored areas. The Jurassic to earliest Cretaceous source rocks have been identified as being the primary sources of the gases and condensates recovered from accumulations in the Browse Basin as follows: - The Lower–Middle Jurassic J10–J20 (Plover Formation) organic-rich source rocks have been deposited along the northeast-southwest trending fluvial-deltaic system associated with a phase of pre-breakup extension. They have charged gas reservoired within J10–J20 accumulations on the Scott Reef Trend and in the central Caswell Sub-basin at Ichthys/Prelude, and in the Lower Cretaceous K40 supersequence on the Yampi Shelf. - Late Jurassic–earliest Cretaceous J30–K10 source rocks are interpreted to have been deposited in a rift, north of the Scott Reef Trend and along the Heywood Fault System (e.g. Callovian–Tithonian J30–J50 supersequences, lower Vulcan Formation). The J30–K10 shales are believed to have sourced wet gas reservoired in the K10 sandstone (Brewster Member) in the Ichthys/Prelude and Burnside accumulations, and potentially similar plays in the southern Caswell Sub-basin. - The organic-rich source rocks observed in the Heywood Graben may be associated with deeper water marine shales with higher plant input into the isolated inboard rift. They are the potential source of fluids reservoired within the Crux accumulation, which has a geochemical composition more closely resembling a petroleum system in the southern Bonaparte Basin.

The Early Cretaceous Gage Sandstone and South Perth Shale formations are a prospective reservoir-seal pair in the Vlaming Sub-basin. Plays include post-breakup pinch-outs in the Gage Sandstone with the South Perth Shale forming top seal. The Gage reservoir has porosities of 18-25% and permeabilities of 1-1340 mD. It was deposited in palaeotopographic lows of the Valanginian breakup unconformity and is the lowstand component of the thick deltaic South Perth (SP) Supersequence. To characterise the reservoir-seal pair, a detailed sequence stratigraphic analysis was conducted by integrating 2D seismic interpretation, well log analysis and new biostratigraphic data. Palaeogeographic reconstructions for the SP Supersequence were derived from mapping higher-order prograding packages and establishing changes in sea level and sediment supply. Higher resolution Gage reservoir reconstructions were based on seismic facies mapping. The Gage reservoir forms part of a sand-rich submarine fan system similar to model proposed by Richards et al (1998). It ranges from canyon confined inner fan deposits to middle fan deposits on a basin plain. Directions of sediment supply are complex, with major sediment contributions from a northern and southern canyon adjacent to the Badaminna Fault Zone. The characteristics of the SP Supersequence differ markedly between the northern and southern parts of the sub-basin due to variations in palaeotopography and sediment supply. Palaeogeographic reconstructions reveal a series of regressions and transgressions leading to infilling of the palaeo-depression. Palaeogeographic reconstructions for the SP Supersequence portray a complex early post-rift depositional history in the central Vlaming Sub-basin. The developed approach is applicable for detailed studies of other sedimentary basins. APPEA

Poster describing how GA made the WASANT palaeovalley map (GEOCAT #73980).

This book describes the evolution of the Australian continent over the last 600 million years. In particular, it focuses on the palaeogeography of Australia. This book is the result of several years' work by a dedicated group of people. The work has begun at the Australian National University by Dr Peter Cook, then the initiative was continued at the BMR. Later work has expanded the study from the Australian continent into the broader context of the supercontinent of Gondwana, and also into more detailed studies of smaller areas of the Australian continental margin. - comprises a 96 page, full colour book with sections on geological time, plate tectonics, the break up of Gondwana, climate and sea level change, evidence for ancient environments & Australia's geological framework. - 70 palaeogeographic maps; Cambrian through to Quaternary - foldout legend - 6 page glossary of relevant terms

A small collection of marine Lower Cretaceous Mollusca from Mount Samuel area, central Western Australia, consists of six genera and seven species which are known from the Roma Formation beds of the Great Artesian Basin. It is suggested that a communicating seaway existed between the Great Artesian Basin and Mount Samuel area during Aptian times. Migration of marine organisms probably took place along a southern route through Officer and Eucla Basins, but may have possibly proceeded directly to the west from Rumbalara. It is also suggested that at the same time another seaway existed between Mount Samuel area and the Dampier Peninsula.The sediments of the Great Artesian Basin occur in two areas in the Northern Territory, viz, in the vicinity and to the east of Rumbalara, at the southern extreme of the Northern Territory where they are of Aptian age and are correlated with beds of Roma Formation in Queensland; and up to about one hundred miles south of the Gulf of Carpentaria, close to the Queensland border, where they are of Aptian and of Upper Albian age and can be correlated with the Roma and Tambo Formation beds of Queensland.

No abstract available