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Pan-Gondwanaland (650-500 Ma) tectonics is dominated by transcurrent motions driven by post-collisional oblique stresses. Extension is commonly marked by the intrusion of alkaline rocks, in particular A-type granite, nepheline syenite, and carbonatites (ARCs), during or after collision, as well as by field studies. ARCs of this age are common in Africa, South America, India, Antarctica, and Australia, and are indicated by related detrital zircons of 650-500 Ma age in Permian-Triassic and younger sediments from Australia, Antarctica, southern Africa, and India. Structural studies suggest that ARCs fill openings at releasing bends along transcurrent fractures and during reversal of the sense of motion as well as during relaxation of stress after collision. On the Paleo-Pacific margin, 550-500 Ma ARCs of the Koettlitz Glacier Alkaline Province were emplaced syn-tectonically within the Ross orogen during oblique subduction. The concentration of ARC magmas emplaced during the amalgamation of Gondwanaland is correlated with the transtension generated by the 650-570 Ma oblique subduction between Avalonia-Cadomia and the West African craton, and the 550-490 Ma oblique subduction of the Paleo-Pacific underneath Antarctica. In the Eastern Ghats and the Prince Charles Mountains of East Antarctica, ARCs and related zircons were generated 1000-900 Ma during an earlier continental collision. Keywords: alkaline rocks; carbonatites; 650-500 Ma; U-Pb; zircons; extension; Gondwanaland

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.earscirev.2005.11.001 Byline: J.J. Veevers (a), E.A. Belousova (a), A. Saeed (a), K. Sircombe (b), A.F. Cooper (c), S.E. Read (c) Keywords: Australia; Antarctica; detrital zircons; 700-500 Ma; Pan-Gondwanaland; Hf-isotopes; trace elements; T .sub.DM; paleogeography; alkaline provenance Abstract: 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 T .sub.DM 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 T .sub.DM 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 T .sub.DM 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. Rocks of this age and type, however, abound in the Pan-Gondwanaland orogens. The nearest of these is the Leeuwin Complex of the Pinjarra orogen of southwestern Australia, which connects through the Prydz-Leeuwin Belt with the Mozambique Orogenic Belt. In turn, the Leeuwin Complex is dominated by 700-500 Ma alkaline rocks generated by contemporary transtension. We find that zircons from a beach sand at Eneabba, 450 km north of the Leeuwin Complex, are dominated by alkaline types, so confirming demonstration by age alone that the sand came from the Leeuwin Complex. An important inference is that Pan-Gondwanaland terranes are potential provenances of sediment with zircons of ages 700-500 Ma, model ages 2.0-1.0 Ga, and alkaline affinity. We compiled the age spectra of our samples with others of the Southwest Pacific-Gondwana igneous component in southern Australia and reviewed their paleogeographical data. The Early Cambrian turbidites of the Kanmantoo Group were deposited from an axial northward paleocurrent that flowed across adjacent Antarctica in Wilkes Land. The Ordovician turbidite was deposited in fore-arc and abyssal fans likewise from a northward paleocurrent that flowed parallel to the uplifted Ross-Delamerian orogen. The Ordovician-Silurian-Devonian Mathinna Supergroup was deposited in a submarine fan system that prograded to the east-northeast from high ground in Antarctica. The Hawkesbury Sandstone was deposited in a braided-river system on a surface that sloped to the north-northeast from high ground in Antarctica. Together with the zircon data, the paleogeographical evidence in the Cambrian, Ordovician, Ordovician-Silurian-Devonian, and Triassic all point to a provenance in Wilkes Land, Antarctica of Pan-Gondwanaland (700-500 Ma) terranes with alkaline rocks. Author Affiliation: (a) GEMOC ARC National Key Centre, Department of Earth and Planetary Sciences, Macquarie University, Sydney NSW 2109, Australia (b) TSRC, School of Earth and Geographical Sciences, University of Western Australia, Crawley WA 6009, Australia (c) Geology Department, University of Otago, PO Box 56, Dunedin, New Zealand Article History: Received 19 April 2005; Accepted 16 November 2005 Article Note: (footnote) [star] Supplementary data associated with this article can be found, in the online version, at doi:10.1016/j.earscirev.2005.11.001.

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 [T.sub.DM] 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 [T.sub.DM] 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 [T.sub.DM] 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. Rocks of this age and type, however, abound in the Pan-Gondwanaland orogens. The nearest of these is the Leeuwin Complex of the Pinjarra orogen of southwestern Australia, which connects through the Prydz--Leeuwin Belt with the Mozambique Orogenic Belt. In turn, the Leeuwin Complex is dominated by 700-500 Ma alkaline rocks generated by contemporary transtension. We find that zircons from a beach sand at Eneabba, 450 km north of the Leeuwin Complex, are dominated by alkaline types, so confirming demonstration by age alone that the sand came from the Leeuwin Complex. An important inference is that Pan-Gondwanaland terranes are potential provenances of sediment with zircons of ages 700-500 Ma, model ages 2.0-1.0 Ga, and alkaline affinity. We compiled the age spectra of our samples with others of the Southwest Pacific Gondwana igneous component in southern Australia and reviewed their paleogeographical data. The Early Cambrian turbidites of the Kanmantoo Group were deposited from an axial northward paleocurrent that flowed across adjacent Antarctica in Wilkes Land. The Ordovician turbidite was deposited in fore-arc and abyssal fans likewise from a northward paleocurrent that flowed parallel to the uplifted Ross--Delamerian orogen. The Ordovician--Silurian-Devonian Mathinna Supergroup was deposited in a submarine fan system that prograded to the east-northeast from high ground in Antarctica. The Hawkesbury Sandstone was deposited in a braided-fiver system on a surface that sloped to the north-northeast from high ground in Antarctica. Together with the zircon data, the paleogeographical evidence in the Cambrian, Ordovician, Ordovician--Silurian--Devonian, and Triassic all point to a provenance in Wilkes Land, Antarctica of Pan-Gondwanaland (700-500 Ma) terranes with alkaline rocks. Keywords: Australia; Antarctica; detrital zircons; 700-500 Ma; Pan-Gondwanaland; Hf-isotopes; trace elements; [T.sub.DM]; paleogeography; alkaline provenance

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 ([T.sub.DM]) 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. Zircons from Collie and Permian and Early Triassic rocks of the northern Perth Basin have an age spectrum with a peak at about 1200 Ma that can be traced to the Albany Province. Differences, however, in Hf-isotope composition indicate that the Collie Coal Measures and the northern Perth Basin sandstones were not derived from the northern part of the Albany Province or from the coastal strip of felsic granitoids. The Perth Basin samples have a second peak age of 600-500 Ma that can be traced to the Leeuwin Block. One of the modern sands has a major peak at 2616 Ma that can be traced to the Yilgam Craton. Compiled with previously published U-Pb zircon age spectra, the analyses provide insights into the paleogeographical history. The Yilgam Craton sloped from the north at 1700 Ma, from the southeast at 1350-1140 and 490 Ma, its eastern part to the east at 300 Ma, and the southern part to the northwest from the Albany Province at 300-255 Ma. Denudational data from apatite fission-track analysis and vitrinite-reflectance studies suggest that the Yilgarn Craton was covered by a ~ 5-km-thick blanket of Permian and Mesozoic sedimentary rock that was almost entirely removed by the Cenozoic, possibly because the craton was situated between the shoulders of rift systems that grew into the eastern and southeastern Indian Ocean. Ordovician, Permian, Early Triassic, and Quaternary sediment of the Perth Basin came from Proterozoic orogens. Only the Late Permian sample contains significant populations of Archean (Yilgarn) zircons but whether they came direct from the craton or were recycled from the postulated sedimentary cover is not known. The increased influx of sediment during the Jurassic matched by a peak in the denudation rate would seem to require a primary supply from the craton. This question could be resolved by dating zircon from the rapidly accumulated Jurassic formations. Keywords: Australia; Yilgarn Craton; Perth Basin; U-Pb ages; Hf-isotopes; Permian sandstone; Modem sand; Source composition; Detrital zircons; Paleogeographical and denudational history

Gondwanaland lasted from the 650-500 Ma (late Neoproterozoic-Cambrian) amalgamation of African and South American terranes to Antarctica Australia--India through 320 Ma (mid-Carboniferous) merging with Laurussia in Pangea to breakup from 185 to 100 Ma (Jurassic and Early Cretaceous). Gondwanaland straddled the equator at 540 Ma, lay wholly in the Southern Hemisphere by 350 Ma, and then rotated clockwise so that at 250 Ma Australia reached the S pole and Africa the equator. By initial breakup of Pangea at 185 Ma, Gondwanaland had moved northward such that North Africa reached 35[degrees]N. The first clear picture of Gondwanaland, in the Cambrian, shows the assembly of continents with later Laurentian, European and Asian terranes along the 'northern' margin, and with a trench along the 'western' and 'southern' margins, reflected by a 10,000-km-long chain of 530-500 Ma granites. The interior was crossed by the Prydz-Leeuwin and Mozambique Orogenic Belts. The shoreline lapped the flanks of uplifts generated during this complex terminal PanGondwanaland (650-500 Ma) deformation, which endowed Gondwanaland with a thick, buoyant crust and lithosphere and a nonmarine siliciclastic facies. During the Ordovician, terranes drilled from Africa as the first of many transfers of material to the 'northern' continents. Central Australia was crossed by the sea, and the eastern margin and ocean floor were flooded by grains of quartz (and 600-500 Ma zircon) from Antarctica. Ice centres in North Africa and southern South America/Africa waxed and waned in the latest Ordovician, Early Silurian, latest Devonian, and Early Carboniferous. In the mid-Carboniferous, Laurussia and Gondwanaland merged in the composite called Pangea by definitive right-lateral contact along the Variscan suture, with collisional stress and subsequent uplift felt as far afield as Australia. Ice sheets developed on the tectonic uplands of Gondwanaland south of 30[degrees]S. In the Early Permian, the self-induced heat beneath Pangea drove the first stage of differential subsidence of the Gondwanaland platform to intercept sediment from the melting ice, then to accumulate coal measures with Glossopteris, and subsequently Early Triassic redbeds. An orogenic zone along the Panthalassan margin propagated from South America to Australia and was terminally deformed in the mid-Triassic. Coal deposition resumed during Late Triassic relaxation in the second stage of Pangean extension. In the Early Jurassic, the vast ~ 200 Ma Central Atlantic magmatic province of tholeiite anticipated the 185 Ma breakup in the Central Atlantic. Another magmatic province was erupted at this time between southern Africa and southeastern Australia. The northeastern Indian Ocean opened from 156 Ma, and the western Indian Ocean from 150 Ma. By the 100 Ma mid-Cretaceous, the Gondwanaland province of Pangea had split into its five constituents, and the Earth had entered the thalassocratic state of dispersed continents. The 650-500 Ma 'Pan-Gondwanaland' events (? by mafic underplating) rendered Gondwanaland permanently geocratic. Pangean (320-185 Ma) tectonics, driven by pulses of self-induced heat, promoted widespread subsidence at 300 Ma Early Permian and 230 Ma Late Triassic. Pangea initially broke up at 185 Ma and the five continental pieces of Gondwanaland had broken apart by the 100 Ma mid-Cretaceous. Another long-lasting feature of Gondwanaland was subduction beneath the 'southern' margin and export of terranes from the 'northern' and 'northwestern' margins. Export of terranes was promoted by Gondwanaland-induced heat, and internal breakup by Pangea-induced heat. Keywords: Gondwanaland; Gondwana facies; Pangea; paleogeography; tectonics; coal

Gondwanaland was assembled by 650-570 Ma oblique subduction of ocean floor between cratons, including the Mozambique Ocean between West and East Gondwanaland. Oblique convergence set the cratons into a series of counterrotating cogs that sheared the intervening fold belts. The 550-490 Ma oblique subduction of paleo-Pacific ocean floor beneath Antarctica extended the system of counterrotating cogs and shear deformation to the Transantarctic Mountains and northern Australia. Terminal subduction was followed by epeirogenic uplift and concomitant stripping indicated by ubiquitous ca. 500 Ma K-Ar and apatite fission-track dates. These deep-seated events, recorded by zircons of 650-500 Ma age, and first noted in Africa ('Pan-African'), are now recognized as 'Pan-Gondwanaland.' Keywords: Gondwanaland, assembly, rotation, oblique convergence, 650-500 Ma.

Gondwanaland was buoyant, as indicated by nonmarine facies, and Laurasia was depressed, as indicated by marine facies. As a supercontinent, Gondwanaland lasted much longer than Laurasia and was hotter from internal heat. Moreover, the Pan-African orogenic cycle, confined to Gondwanaland, augmented the heat supply, which possibly generated a permanently buoyant lower crust by underplating. A crustal layer in the Australian Proterozoic shield with subhorizontal reflectors and velocity ([V.sub.p]) >7.5 km/s is interpreted as mafic underplating beneath latest Neoproterozoic flood basalt. The Pan-African terrane in East Africa also contains evidence of mafic underplating, and most of Gondwanaland (but not Laurasia) was affected by terminal Pan-African (0.5 Ga) uplift and cooling.

Magma was emplaced in the India-Australia rift zone along the Tethyan margin during Permian-Carboniferous and Permian-Triassic time. Permian-Carboniferous alkalic granite and basaltic and rhyolitic lava flows and tuffs formed at the same time as right-lateral transtension of Pangea, as recorded by the magmatic rocks of neocratonic post-Variscan Europe and post-Kanimblan eastern Australia. Permian-Triassic tholeiitic basalt in India, alkalic magmatic rocks in Oman, and rhyolite, dolerite, and undersaturated alkalic volcanic rocks in Western Australia preceded and accompanied the early opening of the Neo-Tethys ocean. Coeval magmatism included the voluminous mid-plate Siberian Traps, the Emeishan Basalt of south China, and the peak activity of the magmatic are along the convergent Panthalassan margin. The background magmatism probably permitted the Siberian Traps to trigger the environmental catastrophe at the Permian-Triassic boundary.

The present drainage of East Antarctica, with ice radiating from a central dome draped over the thick crust of the Gamburtsev Subglacial Mountains, recapitulates the Early Permian scene, including the south polar paleolatitude. The Permian radial drainage was on the same scale as the present drainage around the thick crust of the Tibetan Plateau. Another high region in Carboniferous-Permian time was the upland of Europe on crust thickened during the Variscan collision to form Pangea. The ancestral Gamburtsev Subglacial Mountains and a central Australian upland may have formed because of long-distance stress from the Variscan collision acting on zones of weak crust attenuated during prolonged subsidence of intracratonic basins. The mid-Carboniferous inception of widespread glaciation was possibly linked with vast uplands in northern and southern Pangea through the effects of Variscan topography and the removal of atmospheric C[O.sub.2] during accelerated erosion and weathering.

The Phanerozoic history of continental dispersal and coalescence contains an epoch of radical change at about the Middle/Late Triassic boundary (230 [+ or -]5 Ma), marked by (1) the final coalescence of Pangea by the contact of south China and Cimmeria with Laurasia and terminal compressive deformation in Australia and southern Africa, and (2) the incipient dispersal of Pangea by the onset of continental rifting in eastern North America and northwest Africa, Argentina, east Africa, and Western Australia. This epoch of coalescence and incipient dispersal correlates with a change from (1) an icehouse state to a greenhouse state, and (2) changes, from a fall to a rise, in the sea-level curve, in the emplacement of North America granite, and in the cumulative curve of reversed to normal magnetic polarity. These changes are interpreted as indicating the first major loss from the heat accumulated beneath Pangea, now represented by the Atlantic-African geoid high.

In 1987 C. McA. Powell and J. J. Veevers postulated that the mid-Carboniferous uplift of the Centralian fold-and-thrust belt led to the growth of an ice sheet that covered much of Australia as it drifted from low to high latitudes. They presumed that the voluminous sediment shed from the final disruption and stripping to basement of the Centralian Superbasin was transported by ice streams out of the foreland basin to the edge of the ice sheet in the eastern and west-northwestern margins. Geochronological data accrued since 1987 confirm the 330-320 Ma synchronicity of uplift and exhumation in Centralia, deposition of glacial sediment on the margins and the onset of glacio-eustasy, as indicated by cyclothemic sedimentation patterns in the Visean platform carbonates of the British Isles. These events are by-products of the 330-320 Ma merging of Gondwanaland and Laurussia in Pangaea that provided the global setting for glaciation. Probably more influential in initiating glaciation was the greater uplift in the Gamburtsev Subglacial Mountains of East Antarctica that became the focus of Permian post-glacial dispersal of sediment in East Gondwanaland. [ABSTRACT FROM AUTHOR]

Abstract: 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 (TDM C). Populations of detrital zircons are (1) 700 to 500 Ma, host magmas granitoid and alkaline rock, TDM C ranges from 2.5 to 1.1 Ga, and (2) 1200–800 Ma, host magmas mafic granitoid and alkaline rock, TDM 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. [Copyright &y& Elsevier]

Abstract: 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 (ε 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 (ε 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 ∼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 ∼500 Ma Cambrian. [Copyright &y& Elsevier]

Abstract: 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 T DM 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 T DM 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 T DM 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. Rocks of this age and type, however, abound in the Pan-Gondwanaland orogens. The nearest of these is the Leeuwin Complex of the Pinjarra orogen of southwestern Australia, which connects through the Prydz–Leeuwin Belt with the Mozambique Orogenic Belt. In turn, the Leeuwin Complex is dominated by 700–500 Ma alkaline rocks generated by contemporary transtension. We find that zircons from a beach sand at Eneabba, 450 km north of the Leeuwin Complex, are dominated by alkaline types, so confirming demonstration by age alone that the sand came from the Leeuwin Complex. An important inference is that Pan-Gondwanaland terranes are potential provenances of sediment with zircons of ages 700–500 Ma, model ages 2.0–1.0 Ga, and alkaline affinity. We compiled the age spectra of our samples with others of the Southwest Pacific–Gondwana igneous component in southern Australia and reviewed their paleogeographical data. The Early Cambrian turbidites of the Kanmantoo Group were deposited from an axial northward paleocurrent that flowed across adjacent Antarctica in Wilkes Land. The Ordovician turbidite was deposited in fore-arc and abyssal fans likewise from a northward paleocurrent that flowed parallel to the uplifted Ross–Delamerian orogen. The Ordovician–Silurian–Devonian Mathinna Supergroup was deposited in a submarine fan system that prograded to the east-northeast from high ground in Antarctica. The Hawkesbury Sandstone was deposited in a braided-river system on a surface that sloped to the north-northeast from high ground in Antarctica. Together with the zircon data, the paleogeographical evidence in the Cambrian, Ordovician, Ordovician–Silurian–Devonian, and Triassic all point to a provenance in Wilkes Land, Antarctica of Pan-Gondwanaland (700–500 Ma) terranes with alkaline rocks. [Copyright &y& Elsevier]