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Abstract: The age and composition of the 14×106 km2 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, TDM, 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, TC, 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, TDM C of 3.6–1.3Ga, and mainly negative εHf. The potential provenance of zircons of 650–500Ma age with TDM C 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. [Copyright &y& Elsevier]

Abstract: The age and composition of the 14×106 km2 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, TDM C, 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, TDM C 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. [Copyright &y& Elsevier]

Abstract: 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 T DM 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. T DM 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. [Copyright &y& Elsevier]

Abstract: 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, εHf 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, εHf 11 to −28, signifying derivation 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 εHf in its 1200–900 Ma rocks bounded on either side by positive εHf. 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 ∼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. [Copyright &y& Elsevier]

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]

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.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 Yilgarn Craton.Compiled with previously published U–Pb zircon age spectra, the analyses provide insights into the paleogeographical history. The Yilgarn 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. [Copyright &y& Elsevier]