Recent centuries provide no precedent for the 2004 Indian Ocean tsunami, either on the coasts it devastated or within its source area. The tsunami claimed nearly all of its victims on shores that had gone 200 years or more without a tsunami disaster. The associated earthquake of magnitude 9.2 defied a Sumatra-Andaman catalogue that contains no nineteenth-century or twentieth-century earthquake larger than magnitude 7.9. The tsunami and the earthquake together resulted from a fault rupture 1,500 km long that expended centuries -worth of plate convergence. Here, using sedimentary evidence for tsunamis, we identify probable precedents for the 2004 tsunami at a grassy beach-ridge plain 125 km north of Phuket. The 2004 tsunami, running 2 km across this plain, coated the ridges and intervening swales with a sheet of sand commonly 5-20 cm thick. The peaty soils of two marshy swales preserve the remains of several earlier sand sheets less than 2,800 years old. If responsible for the youngest of these pre-2004 sand sheets, the most recent full-size predecessor to the 2004 tsunami occurred about 550-700 years ago.

No abstract available

2004 updated version of Helby, Morgan & Partridge (1987)

Optically stimulated luminescence (OSL) dating of sand sheets provides a chronology of the largest tsunamis in western Thailand over the late Holocene. Four sand sheets deposited by pre-2004 tsunamis were dated by luminescence to 380 ± 50, 990 ± 130, 1410 ± 190 and 2100 ± 260 years ago (at 1-sigma precision). These compare with previous radiocarbon ages of detrital bark high in buried soils (Jankaew et al., 2008), which suggest that the most recent large-scale predecessor to the 2004 tsunami occurred soon after 550-700 cal BP, and that at least three such tsunamis occurred over the past 3000 years. Concordant OSL ages from successive beach ridges (1600 ± 210 to 2560 ± 350 years ago) and tidal flat deposits (2890 ± 390 years ago) provides a set of limiting maximum ages for sand sheet deposition which, when combined with the sand sheet ages, provide a robust average for tsunami recurrence. The ages imply that between 350 to 700 years separates successive tsunamis on the Andaman coast of Thailand with an average tsunami recurrence interval of 550 years. These results show OSL can provide independent estimates of tsunami recurrence for hazard analysis, particularly in areas where suitable material for radiocarbon dating is unavailable.

This report presents new geochronological results for five uranium deposits in Australia, detailing the timing of uranium mineralisation in relation to regional geological events. The purpose of the study is to better constrain ore genetic and exploration models for these uranium mineral systems, and ultimately to improve understanding of the uranium resource potential of the Australian continent. The work was carried out under the auspices of the Onshore Energy Security Program. Each of the five uranium deposits represents a different style of mineralisation within three broad families of uranium mineral systems: magmatic-related, basin-related, and metamorphic-related. The results contribute to the current paucity of age data for uranium deposits in Australia, and for most of the deposits the new dates are the first reported direct ages for mineralisation or associated alteration.

Canning Basin Chart updated August 2013

This collection consists of type specimens, illustrated or referred specimens which have been published in the scientific literature. Type specimens that have been published in literature of a wide variety of different macro and micro fossils. The Commonwealth Palaeontological Collection is a collection of type, illustrated referred or cited specimens of fossils which have been published in the scientific literature. This Collection was initiated by Federal Cabinet decision during the 1920s. When fossil specimens of any new species of animal or plant are found, for it to be of any future use in biostratigraphy, it of course must be analysed.

The Nolans Bore deposit, located in the Aileron Province of south-central Northern Territory, is an emerging Australian rare earth development. It consists of steeply northwest dipping apatite veins hosted by ~1806 Ma granite gneiss. A preliminary ~1240 Ma U-Pb age for apatite may correspond to a major global period of alkalic magmatism between 1300 and 1130 Ma, including emplacement of the Bayan Obo deposit in China. Low ?Nd and 87Sr/86Sr in the mineralisation is reminiscent of modern EM-1 ocean island basalts and may indicate a link to carbonatitic magmatism. Oxygen isotope thermometry indicates a mineralisation temperature of 410°C, with '18Ofluid of ~8.0'. Fertilisation of the mantle to produce the EM-1 source may relate to subduction associated with convergence along the southern margin of the North Australian Craton.

This set of four charts provide an update of the million year numbers assigned to Australian palynological zone boundaries to the latest Geologic Time Scale 2004, authored by Gradstein et al. (2004), over the geological time interval Jurassic to Recent. These charts have been drafted to help display the relationships of the palynological zones to the new timescale and to assist in scaling the zones and subzones, so that most million year ages assigned to the zone boundaries are mostly numbers with not more than one decimal place.

As part of Geoscience Australia's 2002-2004 work program, the Petroleum and Marine Division initiated a collaborative study of the Otway Basin (Figure 1) with Primary Industries and Resources SA (PIRSA) and the Department of Primary Industries (DPI), Victoria. The aim of the project was to enhance the petroleum prospectivity of the basin through an improved understanding of depositional systems, integrated petroleum systems analysis and enhanced access to basic datasets critical to the exploration industry. Major project work components included seismic- and well-interpretation to construct a new regional chronostratigraphic framework for the basin (Figure 2), geochemistry and geohistory modelling to document regional petroleum systems elements (Boreham et al ., 2004), and biostratigraphy to refine age-control, biozonations and correlations within the basin (Krassay et al ., 2004). Biostratigraphic work for the Otway Basin Project involved a major program of new sampling, processing and palynological analysis combined with a thorough review of existing biostratigraphic reports and data. Collection, processing and preparation of new samples were conducted in-house by Geoscience Australia staff. New palynological analyses were carried out by Morgan Palaeo Associates on a commercial contract basis. This Record (CD-ROM) contains consultants palynological reports (Microsoft Word) and digital data files as originally submitted (wmf and dex formats) and as updated and standardised (csv format) for over 200 new samples collected from 14 selected Otway Basin wells (Table 1). This Record also contains revised palynological data files (csv format) for 18 Otway Basin wells (Table 2). Revision and updating of palynological data from existing reports and new consultants reports involved initial quality-assurance and quality-control of the data followed by updating of synonyms and systematics to comply with a standardised taxonomy. Revised data files contained in this Record adhere to a standardised taxonomy in current use at Geoscience Australia. Revised data files are presented in a csv format (Excel spreadsheets).