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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.

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.

The Lower Darling Valley (LDV) contains Cenozoic shallow marine, fluvial, lacustrine and aeolian sediments capped by a number of Quaternary fluvial units associated with the Darling River and its anabranches, which were poorly dated prior to this study. Recent investigations in the LDV area have used an Airborne Electromagnetic (AEM) survey, a new high-resolution LiDAR survey, sonic drilling, shallow hand-augering, examination of tractor-dug pits, sediment sample analyses, landform mapping, and river bottom profiling in combination with OSL and radiocarbon dating to provide new insights into the nature and chronology of Quaternary fluvial landscape evolution. The Quaternary sequence in the LDV consists of scroll-plain tracts of different ages incised into higher, older and more featureless floodplain sediments. Samples for OSL and radiocarbon dating were taken in tractor-excavated pits, from sonic cores and from hand-auger holes from a number of scroll-plain and older floodplain sediments. The youngest, now inactive, scroll-plain phase associated with the modern Darling River, was active in the period 5-2 ka. A previous anabranch scroll-plain phase has Last Glacial Maximum dates around 20 ka. Less distinct scroll-plain tracts, older than the anabranch system, have ages around 30ka. A poorly preserved scroll-plain phase with very indistinct scroll and channel traces is associated with the Darling River tract and has ages around 45-50 ka. Older dates of 85 ka and >150 ka have been obtained beneath the higher floodplain from lateral-migration sediments that lack visible scroll-plain traces. This chronologic sequence suggests regular recurrence of approximately 5 ka lateral-migration episodes separated by approximately 10 ka periods of quiescence. There is a lack of coincidence with the glacial-interglacial climate cycles. This suggests that the onset and termination of lateral-migration phases is probably a combination of changes in discharge and sediment regimes r

The contemporary crustal stress regime in south-eastern Australia can be traced back to the terminal Miocene. Increased coupling of the Australian and Pacific Plate boundary at this time resulted in regional-scale tilting, local uplift and erosion, and in the formation of unconformities in southern Australian basins. In the onshore Gippsland Basin the unconformity surface is overlain by an extensive sheet of fluvial sediment known as the Haunted Hill Formation (HHF). Open folds and flexures developed within the HHF over blind reverse and reverse oblique faults provide a record of deformation spanning much of the neotectonic period. The predominance of flexures and folds rather than discrete faulting at the surface complicates the assessment of slip rates over the last few seismic cycles. However, ages from an undeformed fill terrace bordering the Morwell River and crossing the Morwell Monocline suggest that it has been a minimum of 70 ka since the last deformation event on at least this structure. Stream profiles crossing the Snake Ridge, Yallourn and Rosedale Monoclines similarly reveal no evidence for recent tectonic displacement. Cosmogenic radionuclide (10Be and 26Al) burial ages of siliceous sediments sampled from tectonically uplifted HHF on the Yallourn, Morwell and Snake Ridge Monoclines provide constraint on the long-term evolution of these structures. Combined with stratigraphic and tectonic records from the offshore Gippsland Basin, these data provide a basis for informed seismic hazard assessment.

This black and white education resource is a 58 page booklet which contains information on geological time, fossilisation, characteristics of major groups of vertebrate and invertebrates, micropaleontology (e.g.. spores and pollen), trace fossils and the uses of fossils. It includes student activities. Suitable for secondary Years 7-10

Bonaparte Basin biostratigraphic chart

The Gawler Craton, South Australia, preserves extensive sedimentary sequences and associated magmatic rocks that span the interval covering the Archaean-Palaeoproterozoic transition, with bimodal calc-alkaline volcanism and associated sedimentation occurring over the interval ~2560-2480 Ma. The pervasive high geothermal gradient metamorphism in the earliest Palaeoproterozoic, ~2470-2420 Ma (Fanning et al., 2007; Jagodzinski et al., 2009) within the Gawler Craton suggests the Gawler Craton is potentially more likely a correlative of the Dhawaar Craton, Sask Craton and other similar terranes, in terms of timing of magmatic and orogenic events (Payne et al., 2009). We report new zircon U-Pb ion probe data collected from Neoarchaean to Earliest Palaeoproterozoic metasedimentary and meta-igneous rocks of the Gawler Craton, South Australia, an important time interval for the development of the Gawler Craton itself that has been investigated by relatively few geochronological studies. The new data show that the interval ~2560-2480 Ma was characterised by deposition and associated magmatism. This was terminated by contractional deformation and high geothermal gradient metamorphism over the interval ~2470-2410 Ma.

Canning Basin Chart updated August 2013