Lower to upper Middle Ordovician quartz-rich turbidites form the bedrock of the Lachlan Orogen in the southern Tasmanides of eastern Australia and occupy a present-day deformed volume of ∼2–3 million km3. We have used U–Pb and Hf-isotope analyses of detrital zircons in biostratigraphically constrained turbiditic sandstones from three separate terranes of the Lachlan Orogen to investigate possible source regions and to compare similarities and differences in zircon populations. Comparison with shallow-water Lower Ordovician sandstones deposited on the subsiding margin of the Gondwana craton suggests different source regions, with Grenvillian zircons in shelf sandstones derived from the Musgrave Province in central Australia, and Panafrican sources in shelf sandstones possibly locally derived. All Ordovician turbiditic sandstone samples in the Lachlan Orogen are dominated by ca 490–620 Ma (late Panafrican) and ca 950–1120 Ma (late Grenvillian) zircons that are sourced mainly from East Antarctica. Subtle differences between samples point to different sources. In particular, the age consistency of late Panafrican zircon data from the most inboard of our terranes (Castlemaine Group, Bendigo Terrane) suggests they may have emanated directly from late Grenvillian East Antarctic belts, such as in Dronning Maud Land and subglacial extensions that were reworked in the late Panafrican. Changes in zircon data in the more outboard Hermidale and Albury-Bega terranes are more consistent with derivation from the youngest of four sedimentary sequences of the Ross Orogen of Antarctica (Cambrian–Ordovician upper Byrd Group, Liv Group and correlatives referred to here as sequence 4) and/or from the same mixture of sources that supplied that sequence. These sources include uncommon ca 650 Ma rift volcanics, late Panafrican Ross arc volcanics, now largely eroded, and some <545 Ma Granite Harbour Intrusives, representing the roots of the Ross Orogen continental-margin arc. Unlike farther north, Granite Harbour Intrusives between the Queen Maud and Pensacola mountains of the southern Ross Orogen contain late Grenvillian zircon xenocrysts (derived from underlying relatively juvenile basement), as well as late Panafrican magmatic zircons, and are thus able to supply sequence 4 and the Lachlan Ordovician turbidites with both these populations. Other zircons and detrital muscovites in the Lachlan Ordovician turbidites were derived from relatively juvenile inland Antarctic sources external to the orogen (e.g. Dronning Maud Land, Sør Rondane and a possible extension of the Pinjarra Orogen) either directly or recycled through older sedimentary sequences 2 (Beardmore and Skelton groups) and 3 (e.g. Hannah Ridge Formation) in the Ross Orogen. Shallow-water, forearc basin sequence 4 sediments (or their sources) fed turbidity currents into outboard, deeper-water parts of the forearc basin and led to deposition of the Ordovician turbidites ∼2500–3400 km to the north in backarc-basin settings of the Lachlan Orogen.

We test the hypothesis that the Transgondwanan Supermountains at the collision of East and West Gondwanaland were the provenance of a vast turbiditic fan that stretched alongside the East Gondwanaland margin to eastern Australia which, in turn, became the provenance of sediment shed into interior Australia to the Cretaceous Ceduna Delta in central-southern Australia and the modern Channel Country of central Australia. We employ an integrated analysis (U-Pb, Lu-Hf isotopes and trace elements) of detrital zircons in the Ceduna Delta and Channel Country. The main properties of the detrital zircons are U-Pb ages of 700-500 Ma (model ages T-DM(C) 2.5-1.0 Ga; epsilon Hf + 10 to 20) and 1300-1000 Ma ages (T-DM(C) 2.7-1.3 Ga; epsilon Hf +4 to 17), in hosts of mafic granitoids with alkaline affinity. Zircons with these properties can be traced back through the drainage/paleo-slope to the intermediate provenances of the Ordovician turbidites and S-type granitoids of the Lachlan Orogen, then up-paleoslope to the primary or secondary provenance of the ancestral Gamburtsev Subglacial Mountains, and finally to the primary provenance of the Transgondwanan Supermountains atop the 700-500 Ma East African-Antarctic Orogen. Another primary provenance, the 140-95 Ma Whitsunday Volcanic Province/New Caledonia arc in northeastern Australia, also shed sediment across Australia to the Ceduna Delta.We suggest that the primary sediment from the 700-500 Ma East African-Antarctic Orogen and the ancestral Gamburtsev Subglacial Mountains was shed into a deep-sea super-fan to (1) Ordovician turbidites in southeast Australia, recycled by melting of the turbidites to (2) 450 Ma S-type granites in the Lachlan Orogen, and (3) finally deposited, together with volcanogenic sediment from northeast Australia, in the Ceduna Delta. Zircons in the Channel Country and the Ceduna Delta have essentially the same properties, and indicate that the northeastern Australian provenance was largely unchanged over the past 100 Ma. (C) 2016 Elsevier B.V. All rights reserved.

Interpretation of deep seismic reflection profiling, coupled with forward modelling of gravity and aeromagnetic data, new zircon U–Pb dating and the interpretation of the basement geology beneath the southern margin of the Eromanga Basin, has provided insights into the southern part of the underlying Thomson Orogen and its relationship with the Lachlan Orogen to the south. Our interpretations of these data suggest that the northern Lachlan and southern Thomson orogens had a shared history from the mid-Silurian to the Carboniferous. Major older differences, however, are suggested by the presence in the southern Thomson Orogen of: (i) a possible Neoproterozoic arc, (ii) latest Cambrian to earliest Ordovician turbidites, (iii) Late Ordovician turbidites, and (iv) geophysical evidence for thrusting of reflective ocean crust rocks high into the crust on a north-dipping detachment. The seismically imaged, north-dipping, crustal-scale Olepoloko Fault corresponds to the ‘surface expression’ of the Thomson–Lachlan boundary. We speculate that it reflects the partial reactivation and short-cutting of an older fault in the post-Devonian (?Carboniferous) and probably also in the latest Silurian and Early Devonian. Comparisons with the seismic architecture of the Lachlan Orogen immediately to the south, and with the central part of the Thomson Orogen ∼450 and 650 km to the north, suggest that the part of the Thomson Orogen west of the Quilpie Trough and the Nebine Ridge developed on inferred Neoproterozoic to Cambrian oceanic crust that floors the Barcoo Basin. This basin separated the continental margin at that time on the west from a sliver of continental crust preserved at Anakie on the east that was overlain by one or more, poorly dated, passive margin sedimentary ± volcanic sequences that predate a 500 Ma deformation. The southern margin of the Thomson Orogen also contains a sliver of old continental crust, sandwiched between the southern strike-slip margin of the Barcoo Basin to the north and the open proto-Pacific ocean to the south. It was locally the site of ca 580 Ma subduction, because seafloor spreading to the south lay oblique to the orogen margin. We suggest that the Thomson Orogen and Lachlan Orogen were amalgamated by the late Middle Ordovician, although the Thomson–Lachlan boundary remained a zone of weakness at least until the Triassic.

The age and composition of the 14×106km2 of Antarctica's surface obscured by ice is unknown except for some dated detrital minerals and erratics. In remedy, we present four new analyses (U–Pb age, TDMC, εHf, and rock type) of detrital zircons from Neogene turbidites as proxies of Antarctic bedrock, and review published proxies: detrital hornblendes analysed for Ar–Ar age and bulk Sm–Nd isotopes; Pb isotope compositions of detrital K-feldspars; erratics and dropstones that reflect age and composition; and recycled microfossils that reflect age and facies. This work deals with the 240°E–0°–015°E sector, and complements Veevers and Saeed's (2011) analysis of the 70°E–240°E sector. Each sample is located in its ice-drainage basin for backtracking to the potential provenance. Gaps in age between sample and upslope exposure are specifically attributable to the provenance. The major provenance of detritus west of the Antarctic Peninsula (AP) is West Antarctica, and of detritus east of the AP East Antarctica. We confirm that the Central Antarctic provenance about a core of the Gamburtsev Subglacial Mountains (GSM) and the Vostok Subglacial Highlands (VSH) contains a basement that includes igneous (mafic granitoids) and metamorphic rocks with peak U–Pb ages of 0.65–0.50, 1.20–0.9, 2.1–1.9, 2.8–2.6, and 3.35–3.30Ga, TDMC of 3.6–1.3Ga, and mainly negative εHf. The potential provenance of zircons of 650–500Ma age with TDMC ages of 1.55Ga, and of zircons of 1200–900Ma age with positive εHf lies beneath the ice in East Antarctica south and southeast of Dronning Maud Land within the Antarctic part of the East African–Antarctic Orogen. Zircons with the additional ages of 1.7–1.4Ga, 2.1–1.9Ga, and 3.35–3.00Ga have a potential provenance in the GSM.

The age and composition of the 14×106km2 of Antarctica's surface obscured by ice is unknown except for some dates on detrital minerals. In remedy, we bring together proxies of Antarctic bedrock in the form of (1) detrital zircons analysed for U–Pb age, TDMC, εHf, and rock type, including five new analyses of Neogene turbidites, (2) erratics that reflect age, composition, and metamorphism, and (3) recycled microfossils that reflect age, facies, and metamorphism. Each sample is located in its ice-drainage basin for backtracking to the potential provenance. Gaps in age between sample and upslope exposure are specifically attributable to the provenance. This work indicates that the central Antarctic provenance about a core of the Gamburtsev Subglacial Mountains (GSM) and Vostok Subglacial Highlands (VSH) contains a basement that includes igneous (mafic granitoids) and metamorphic rocks with peak U–Pb ages of 0.5–0.7, 0.9–1.3, 1.4–1.7, 1.9–2.1, 2.2–2.3, 2.6–2.8, and 3.15–3.35Ga, TDMC 1.3–3.6Ga, and εHf +12 to −40. Other modelled cratons with similar ages are set in a matrix of foldbelts of 0.5–0.7Ga age. The basement in the core is surmounted by Permian red beds, at the periphery by Permian and Triassic sedimentary rocks unaffected by igneous heating or load metamorphism, and west of the Transantarctic Mountains (TAM) in the Wilkes Basin arguably by Late Cretaceous through Pliocene marine sediments. Erratics of undated red sandstone along the coast of Wilkes Land and George V Land indicate a red-bed provenance in the interior. The Prince Charles Mountains (PCM) provide an exposed example of a crust of Precambrian igneous and metamorphic rocks and Permian and Triassic sedimentary rocks.

The Ordovician Macquarie Arc in the eastern subprovince of the Lachlan Orogen, southeastern Australia, is an unusual arc that evolved in four vertically stacked volcanic phases over ~ 37 million years, and which is flanked by coeval, craton-derived, passive margin sedimentary terranes dominated by detrital quartz grains. Although these two terranes are marked by a general absence of provenance mixing, LA-ICPMS analysis of U–Pb and Lu–Hf contents in zircon grains in volcaniclastic rocks from 3 phases of the arc demonstrates the same age populations of detrital grains inherited from the Gondwana margin as those that characterise the flanking quartz-rich Ordovician turbidites. Magmatic Phase 1 is older, ~ 480 Ma, and is characterised by detrital zircons grains with ages of ~ 490–540 with negative εHf from 0 to mainly –7.78, 550–625 Ma ages with negative εHf from 0 to −26.6 and 970–1250 Ma (Grenvillian) with εHf from + 6.47 to −6.44. We have not as yet identified any magmatic zircons related to Phase 1 volcanism. Small amounts of detrital zircons also occur in Phase 2 (~ 468–455 Ma), hiatus 1 and Phase 4 (~ 449–443 Ma), all of which are dominated by Ordovician magmatic zircons with positive εHf values, indicating derivation from unevolved mantle-derived magmas, consistent with formation in an intraoceanic island arc. Because of the previously obtained positive whole rock εNd values from Phase 1 lavas, we rule out contamination from substrate or subducted sediments. Instead, we suggest that during Phase 1, the Macquarie Arc lay close enough to the Gondwana margin so that volcaniclastic rocks were heavily contaminated by detrital zircon grains shed from granites and Grenvillian mafic rocks mainly from Antarctica (Ross Orogen and East Antarctica) and/or the Delamerian margin of Australia. The reduced nature of a Gondwana population in Phase 2, hiatus 1 and Phase 4 is attributed to opening of a marginal basin between the Gondwana margin and the Macquarie Arc that put it out of reach of all but rare turbiditic currents.

The Permian-Jurassic Mahanadi and Pranhita-Godavari Rifts are part of a drainage system that radiated from the Gamburtsev Subglacial Mountains in central Antarctica. From 12 samples we analysed detrital zircons for U-Pb ages, Hf-isotopes, and trace elements to determine the age, rock type and source of the host magma, and Tom model age. Clusters, in decreasing order of abundance, are (1) 820-1000 Ma, host magmas felsic granitoids with alkaline rock, (2) 1500-1700 Ma felsic granitoids, (3) 500 to 700 Ma mafic granitoids with alkaline rock, (4) 2400-2550 Ma granitoids, and (5) 1000-1200 Ma felsic and mafic granitoids, mafic rock, and alkaline rock. Tom ranges from 1.5 to 3.5 Ga. Joint paleoslope measurements and zircon ages indicate that the Eastern Ghats Mobile Belt (EGMB) and lateral belts and conjugate Antarctica are potential provenances. Zircons from the Gondwana Rifts differ from those in other Gondwanaland sandstones in their predominant 820-1000 Ma and 1500-1700 Ma ages (from the EGMB and conjugate Rayner-MacRobertson Belt) that dilute the 500-700 Ma (Pan-Gondwanaland) ages. The 1000-1200 Ma zircons reflect the assembly of Rodinia, the 500-700 Ma ones that of Gondwanaland; the other ages reflect collisions in the region. (C) 2009 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

Modern geochronology has moved beyond the acquisition of dates: the goal is to understand the significance of these numbers for the geodynamic evolution of Earth at all scales. The coupling of the laser-ablation microprobe (LAM) to inductively coupled plasma mass spectrometers (ICPMS, multicollector (MC)-ICPMS) has revolutionised geochronology and geochemistry over the last 10 years. These systems enable the rapid and precise in situ analysis of trace-element patterns and isotopic systems, while adding information related to microstructural context and major-element composition. The integration of these multiple sources of data is crucial in constraining the origin of the sample and the processes leading to its formation, so that we can understand the meaning of a date in terms of geological events. LAM-ICPMS measurement of U-Pb ages and trace-element patterns in zircon, coupled with LAM-MC-ICPMS analysis of Hf isotopes in the same grains, gives new insights into the processes of magma genesis. Applied to detrital zircons from modern drainages or sedimentary rocks (the TerraneChron approach), it becomes a powerful tool to investigate problems of crustal evolution on scales ranging from single terranes to continents. The in situ analysis (LAM-MC-ICPMS) of Re-Os systematics in single grains of sulfides in mantle-derived peridotites has demonstrated that most mantle rocks contain several generations of Os-bearing sulfides; whole-rock analyses are mixtures reflecting multiple melting and metasomatic events in the lithospheric mantle. These deep-seated events are commonly mirrored in the crust; Os model-age spectra from xenolith suites show age 'peaks' that correspond to the ages of thermal/tectonic events in the overlying crust, suggesting strong linkages between crust and mantle. Integrated studies of the timing and nature of crustal and mantle events, using these techniques, will be important for understanding the large-scale dynamics of the Earth.

Clasts of red siltstone with Glossopleris from moraine around Mt Rymill in the southern Prince Charles Mountains, East Antarctica, can be traced upslope in the Lambert Graben system to the nearby Gamburtsev Subglacial Mountains (GSM). The clasts contain zircons with SHRIMP U-Pb ages of 620-460 Ma and 1300-970 Ma from host rocks of intermediate to mafic rocks, and a clay fraction with a T-DM Nd model age of 2.72 Ga and eNd of - 18.3, derived from upper continental crust. East of the GSM, at Lake Vostok, clasts of siltstone in accreted ice can be traced to the Vostok Subglacial Highlands (VSH). The clasts contain zircons and monazites with SHRIMP U-Pb ages [Leitchenkov, G.L., Belyatsky, B.V, Rodionov, N.V., Sergeev, S.A., 2007. Insight into the geology of the East Antarctic hinterland: a study of mineral inclusions from ice cores of the Lake Vostok borehole. In: Cooper, A.K., Raymond, C.R. (Eds.), Online Proceedings of the 10th ISAES, USGS Open-file Report 2007-1047, Short research Paper 0 14, 4 pages.] broadly similar to those from Mt Rymill, and a T-DM Nd model age of 1.88 Ga and epsilon Nd of - 15 [Delmonte, B., Petit, JR., Basile-Doelsch, I., Lipenkov, V., Maggi, V., 2004. First characterization and dating of East Antarctic bedrock inclusions from subglacial Lake Vostok accreted ice. Environmental Chemistry 1, 90-94.]. Other Mesozoic and Paleozoic sediments deposited in a radial pattern about central Antarctica contain detrital zircons dominated by populations aged 700-500 Ma and 1300-1000 Ma, which we interpret as reflecting a GSM-VSH provenance dominated by rocks generated during the Pan-Gondwanaland and Grenville events of supercontinental assembly. (C) 2007 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

Permian-Triassic drainage radiates from the Gamburtsev Subglacial Mountains (GSM) in central Antarctica. Proximal to the GSM are Permian-Triassic fluvial sandstones in the Prince Charles Mountains (PCM), and neighbouring ?Triassic red beds in Prydz Bay (PB) ODP740A. We analysed detrital zircons for U-Pb ages, Hf-isotope compositions, and trace elements to determine the age, rock-type and source of the host magma, and "crustal" model age (T-DM(C)).Populations of detrital zircons are (1) 700 to 500 Ma, host magmas granitoid and alkaline rock, T-DM(C) ranges from 2.5 to 1.1 Ga, and (2) 1200-800 Ma, host magmas mafic granitoid and alkaline rock, T-DM(C) 2.1 to 1.5 Ga. The bedrock of the PCM-PB region is a potential provenance of the detrital zircons, but the same populations in Permian siltstone south of the PCM and in sediment inclusions in ice at Lake Vostok indicate that the GSM-Vostok Subglacial Highlands (VSH) are the main provenance. Similar detrital zircons in other sandstones in Gondwanaland downslope from a wider central Antarctic reflect an upslope provenance including the GSM-VSH as a complex of 1200-800 Ma (Grenville) and older cratons with mafic granitoids embedded in 700-500 Ma fold belts with granitoids and alkaline rocks. During the past 1000 Ma, the GSM has undergone intermittent uplift on a scale resembling that of the present uplands of Central Asia. (C) 2007 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

In central Antarctica, drainage today and earlier back to the Paleozoic radiates from the Gamburtsev Subglacial Mountains (GSM). Proximal to the GSM past the Permian-Triassic fluvial sandstones in the Prince Charles Mountains (PCM) are Cretaceous, Eocene, and Pleistocene sediment in Prydz Bay (ODP741,1166, and 1167) and pre-Holocene sediment in AM04 beneath the Amery Ice Shelf. We analysed detrital zircons for U-Pb ages, Hf-isotope compositions, and trace elements to determine the age, rock type, source of the host magma, and "crustal" model age (T-DM(C)). These samples, together with others downslope from the GSM and the Vostok Subglacial Highlands (VSH), define major clusters of detrital zircons interpreted as coming from (1) 700 to 460 Ma mafic granitoids and alkaline rock, epsilon Hf 9 to -28, signifying derivation 2.5 to 1.3 Ga from fertile and recycled crust, and (2) 1200-900 Ma mafic granitoids and alkaline rock, epsilon Hf 11 to -28, signify inderivation 1.8 to 1.3 Ga from fertile and recycled crust. Minor clusters extend to 3350 Ma. Similar detrital zircons in Permian-Triassic, Ordovician, Cambrian, and Neoproterozoic sandstones located along the PaleoPacific margin of East Antarctica and southeast Australia further downslope from central Antarctica reflect the upslope GSM-VSH nucleus of the central Antarctic provenance as a complex of 1200-900 Ma (Grenville) mafic granitoids and alkaline rocks and older rocks embedded in 700-460 Ma (Pan-Gondwanaland) fold belts. The wider central Antarctic provenance (CAP) is tentatively divided into a central sector with negative epsilon Hf in its 1200-900 Ma rocks bounded on either side by positive epsilon Hf.The high ground of the GSM-VSH in the Permian and later to the present day is attributed to crustal shortening by far-field stress during the 320 Ma mid-Carboniferous collision of Gondwanaland and Laurussia. Earlier uplifts in the similar to 500 Ma Cambrian possibly followed the 700-500 Ma assembly of Gondwanaland, and in the Neoproterozoic the 1000-900 Ma collisional events in the Eastern Ghats-Rayner Province at the end of the 1300-1000 Ma assembly of Rodinia. (C) 2008 Elsevier B.V. All rights reserved.

Paleoproterozoic granite gneiss (GGn), mafic volcanics, and associated quartzite are exposed widely in the outer Kumaun Lesser Himalaya, which form an integral part of the Lesser Himalayan belt. Field relation, phase petrology, whole-rock geochemistry, and zircon U-Pb-Lu-Hf isotopes of GGn and enclosed microgranular enclaves (ME) have been investigated to infer the magmatic processes, tectonic setting and its implications on understanding the Paleoproterozoic crustal evolution of the north Indian block (NIB). The U-Pb zircon crystallization ages of GGn (1824 ± 16 Ma) and ME (1804 ± 16 Ma) underline their coeval nature. Modally, the GGn and the ME represent monzogranite and geochemically, they can be characterized as peraluminous, alkali-calcic, calc-alkaline, and ferroan types. Whole-rock elemental and biotite-zircon geochemistry reveal shallow level emplacement, reduced condition, and low water content of GGn magma similar to anorogenic A-type magma. The hybrid (crustal and mantle mixed) origin for the Paleoproterozoic GGn is envisaged, where synchronous mafic volcanics might have served as potential magma end-member. The present and published geochemical and zircon U-Pb-Lu-Hf isotopic record on the Lesser Himalayan felsic-mafic magmatic rocks propose a viable petrogenetic model for the evolution of Paleoproterozoic NIB crust that formed dominantly by the melting of ancient and juvenile crustal sources during 1.8–1.9 Ga.

In conjugate SE Africa and Antarctica, Early Permian sandstones of the Swartrant Formation of the Ellisras Basin, Vryheid Formation of the Karoo Basin, and Amelang Plateau Formation of Dronning Maud Land (DML) were deposited after Gondwanan glaciation on a westward paleoslope. We analysed detrital zircons for U-Pb ages by a laser ablation microprobe-inductively coupled plasma mass spectrometer (LAM-ICPMS) and attached age significance only to clusters of three or more overlapping analyses. We analysed Hf-isotope compositions by a multi-collector spectrometer (LAM-MC-ICPMS) and trace elements by electron microprobe (EMP) and ICPMS. These analyses indicate the rock type and source (whether crustal or juvenile mantle) of the host magma, and a "crustal" model age (T-DM(C)). The integrated analysis gives a more distinctive, and more easily interpreted, picture of crustal evolution in the provenance area than age data alone.Zircons from the Ellisras Basin are aged 2700-2540 Ma with minor populations about 2815 Ma and 2040 Ma, which correspond with the ages of the upslope parts of the proximal Kaapvaal Craton and Limpopo Belt. Mafic rock is the dominant host rock, and it reflects the Archean granite-greenstone terrane of the Kaapvaal Craton.The three Karoo Basin samples and the two DML samples have zircons with these common properties: (1) 1160-880 Ma, host magma mafic granitoid (< 65% SiO2) derived from juvenile depleted mantle sources (epsilon(Hf) positive) at 1.65 Ga and 1.35 Ga, with T-DM(C), of 2.0-0.9 Ga; (2) 760 to 480 Ma, host magma granitoid and low-heavy rare earth element rock (?alkaline rock-carbonatite), derived from mixed crustal and juvenile depleted mantle sources (epsilon(Hf) positive and negative) at 1.50 Ga and 1.35 Ga, with T-DM(C) of 2.0-0.9 Ga. Together with similar detrital zircons in Triassic sandstone of SE Australia, these properties reflect those in upslope central Antarctica, indicating a provenance of similar to 1000 Ma (Grenville) cratons embedded in 700-500 Ma (Pan-Gondwanaland) fold belts. Detrital zircons in Cambrian sediments of the Ellsworth-Whitmore Mountains block and Cambrian metasediments of the Welch Mountains with comparable properties suggest that the central Antarctic provenance operated also in the similar to 500 Ma Cambrian. (c) 2007 Elsevier B.V. All rights reserved.

Eastern Australian sediments of Cambrian, Ordovician, Silurian–Devonian, Triassic, and Neogene ages are known to be dominated by zircons dated 700–500 Ma (“Southwest Pacific–Gondwana igneous component”) by the U–Pb SHRIMP method, and thought to be derived from Antarctica, as suggested also by paleogeographical evidence. To extend the characteristics of the provenance we subjected SHRIMPed zircons from the Middle Triassic Hawkesbury Sandstone and four Neogene beach sands to LAM–ICPMS analysis for rock type and Hf-isotope TDM model ages. These data confirm the demonstration (from ages alone) that the beach sands were recycled from the Hawkesbury Sandstone. All five samples have a substantial fraction of 700–500 Ma zircons derived from alkaline rocks with TDM of 2.0–1.0 Ga. We analysed zircons from the nearest exposed alkaline rock of appropriate age in Antarctica: the 550–500 Ma Koettlitz Glacier Alkaline Province of the Ross orogen of the Transantarctic Mountains, emplaced during contemporary transtension. The rock types and TDM of the Koettlitz Glacier Alkaline Province zircons match those of the eastern Australian samples but only over the restricted range of 550–500 Ma. Rocks of 700–550 Ma age and alkaline type are unknown in Antarctic exposures.

A database of > 600 analyses of the zircon “standard” Harvard 91500 shows considerable heterogeneity in 176Hf/177Hf; the distribution is essentially bimodal with major peaks at 0.282284 ± 22 and 0.282330 ± 29 (2σ). Although the zircon shows a wide range of 176Yb/177Hf and 176Lu/177Hf, there is no correlation of 176Hf/177Hf with either parameter. This isotopic heterogeneity limits the degree to which 91500 can be used to evaluate the precision or accuracy of different treatments of mass bias and overlap corrections for in situ analysis of Hf-isotope compositions in zircons, or differences between solution and in situ data.

Detrital zircons from the Permian Collie Coal Measures and modern sands on the northern part of the Albany Province have been analysed for U–Pb ages by a laser ablation microprobe-inductively coupled plasma mass spectrometer (LAM-ICPMS) and for Hf-isotope compositions by a laser ablation microprobe multi-collector inductively coupled plasma mass spectrometer (LAM-MC-ICPMS). Trace elements were determined by analysis on the electron microprobe (EMP) and the ICPMS's. This combination of techniques makes it possible to determine for each grain not only the age but the nature and source of the host magma, whether crustal or juvenile mantle, and a model age (TDM) based on a depleted-mantle source, which gives a minimum age for the source material of the magma from which the zircon crystallised. The integrated analysis, applied to suites of detrital zircon, gives a more distinctive, and more easily interpreted, picture of crustal evolution in the provenance area than age data alone. Zircons from Permian and Triassic sediments already analysed for U–Pb ages by a sensitive high-resolution ion microprobe (SHRIMP) were also analysed for Hf isotopes and trace elements.

The Moelv Tillite is the Late Neoproterozoic Varanger glacial deposit recorded in the Hedmark Group, SE Norway. Paired U-Pb and Lu-Hf data collected on detrital zircons in the Rendalen Formation underlying the Moelv Tillite have identified an uncommon 677 +/- 15 to 620 +/- 14 Ma population, that constrain the deposition of the Moelv Tillite to be younger than 620 +/- 14 Ma. The youngest detrital zircons may be derived from granite magmatism related to the 616 +/- 3 Ma Egersund dolerite magmatism, situated in the western part of the Sveconorwegian orogen. The Moelv Tillite, which is not overlain by a cap carbonate, possibly correlates with the c. 580 Ma Squantum-Gaskiers glacial deposits of Avalonia. Available palaeomagnetic data for the Late Neoproterozoic suggest that Baltica was located at intermediate to high latitude between 620 and 555 Ma.

The Blefjell quartzite is ca. 40×6–10km gneissic metasupracrustal occurrence deposited on a 1159±8Ma old felsic volcanite. It is part of a mature beach — shallow shelf complex deposited between ca. 1155 and 1145Ma. LAM-ICPMS U-Pb ages of single, detrital zircons range from 1.40 to 2.07Ga, with frequency maxima in the age-range 1.65–1.90Ga. Younger zircons (1.53–1.64 and 1.40–1.50Ga are less abundant. Present-day 176Hf/177Hf ranges from 0.2814 to 0.2822, corresponding to ɛHf(t) between −8 and +14. The minor and trace element distribution of the zircons suggest derivation from a range of mafic to granitic protosources, characterized by distinct, relative LREE enrichment or HREE depletion. The data confirm the presence of important 1.7–1.9Ga protosources for Precambrian sediments in S Norway, indistinguishable in age and crustal history from rocks of the Transscandinavian Igneous Belt. This lends further support to regional tectonic models in which southern Norway west of the Oslo Rift has been an integral part of the Baltic Shield since the formation of the regional protolith in the Paleoprotoerozoic.