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[Display omitted] • Maizuru back-arc basin evolved in Permian and closed with a deposition of breccia. • Hydraulic fracturing in clast, interclast fracture-vein imply brittle deformation. • Paleostress orientation calculation shows a broad NW-SE compression. • This deformation event was active before the deposition of overlying sandstone. • Basin closure at P-Tr boundary is due to complex plate subduction in East Asia. The paleo-continental reconstruction of Asia during the Permian–Triassic boundary indicates major tectonic readjustments between multiple continental blocks in the north of North China Craton (NCC) due to complex plate subduction system(s). One of the major consequences was the closure of the Paleo-Asian Ocean. In a similar time frame, Proto-Japan was also evolving through plate-subduction with the opening of the Maizuru back-arc basin. The spectacular linear near-continuous belt of the Maizuru Terrain in the Inner Zone of Southwest Japan holds the rock record of the opening of the back-arc basin, sediment-fill in this basin culminating into closure-related pulsative debris flow deposits (i.e. the Tonoshiki Formation). However, the exact deformation mechanism(s), paleo-stress regime, their mesoscopic to microscopic rock record, and exact timing hold the keys to connecting the closure event of the Maizuru back-arc basin and the possible tectonics, in particular the closure of the PAO in Asia. With this aim, we report here the micro- to meso -structural geological records of rock units of the Maizuru Terrane which indicate evidence of (1) pre-depositional hydrofracturing, (2) extensive syn -lithification fracture-vein formation due to (3) broad WNW-ESE to E-W compressional paleostress regime using the fracture-vein analysis, (4) deformational e-twin development with the dominance of Type II twin indicating a maximum temperature of 300 °C with no evidence of overprinting. This brittle deformation affected all the lithounits of the Maizuru back-arc basin but not the overlying units deposited after the basin closure. New U-Pb detrital zircon age data of the rocks belonging to the Maizuru Group and also the overlying Fukumoto Formation fixes the age of the above-mentioned deformation event at ∼ 250 Ma. All these data help to assess the possible paleo-position of Proto-Japan and a clear tectonic scenario between the NCC, the Central Asian Orogenic Belt, and the Khanka-Jiamusi Massif in East Asia. [ABSTRACT FROM AUTHOR]

The Huizachal–Peregrina Anticlinorium in northeastern Mexico comprises a wide variety of Precambrian and Paleozoic basement units. In this work, Silurian-to-Permian unmetamorphosed siliciclastic successions (i.e., Cañón de Caballeros, Vicente Guerrero, Del Monte, and Guacamaya formations) forming the Tamatán Group is described; the group overlies the Novillo metamorphic complex, which is the northernmost exposed region of the Oaxaquia microcontinent. In this paper, a provenance model for the Tamatán Group is proposed based on new petrological data, whole-rock geochemical data, and U–Pb LA-ICP-MS detrital zircon age data from these marine fossiliferous strata. The results show a shallow-marine to deep-water clastic succession classified as feldspatho-lithic-quartzose and litho-feldspatho-quartzose (Cañón de Caballeros and Vicente Guerrero formations) and feldspatho-quartzo-lithic and litho-quartzo-feldspathic (Del Monte and Guacamaya formations). The petrological and geochemical data indicate a derivation from felsitic, intermediate, and basic rocks, intense to moderate weathering, and high to moderate recycling of the source area. The geochronological data can be organized into three main detrital zircon U–Pb age groups: (1) a Meso-Neoproterozoic group, likely derived from Oaxaquia and the Maya block, which is also the probable source of 1.5–1.6 Ga zircon grains; (2) an Ordovician–Silurian group that is likely sourced by igneous Maya Block intrusions or from local units such as the Ordovician Peregrina Tonalite; and (3) Pennsylvanian and Permian zircon that can be derived from magmatic arc-related intrusions from the diachronous Rheic closure. Additionally, major, trace, and rare earth element concentrations and ratios from the Tamatán Group indicate a passive margin that evolved into magmatic arc sources within the upper continental crust. The integration of our data indicates that the Tamatán Group was deposited in an unreported back-arc basin from the northernmost part of Oaxaquia near the Maya Block along the northwestern Gondwanan margin during the closure of the Rheic Ocean priori to complete Pangea. Unlabelled Image • Ordovician-Silurian: Passive margin basin with high affinity to Oaxaquia. • Carboniferous: Connection to the Maya Block, first erosion of the Novillo Complex. • Early Permian: Influence of an oceanic island arc system. [ABSTRACT FROM AUTHOR]

The Pan-African and Brasiliano orogenies endowed West Gondwanaland with U–Pb 700–500 Ma zircons, which, together with 1200–1000 Ma zircons from Rodinian collisions, are scattered in the Ediacaran–Paleozoic syn- and post-tectonic molassic outflow from the orogens. A more complete (T DM , εHf) isotopic signature in places narrows the search for provenance but exclusive use of the signature is of limited value given the ubiquity of primary and secondary 700–500 Ma and 1200–1000 Ma zircons. To overcome this shortcoming, I link the detrital-zircon signature with paleogeographical indicators of downslope preserved in minor sedimentary structures generated by gravity currents: the cross-dip azimuth in fluvial sediments, flute marks and other vectorial markings in turbidites. The prominent East African-Antarctic Orogen (EA-AO) trends through Africa-Arabia southward through East Africa/Madagascar to Dronning Maud Land in Antarctica. Squire et al. (Squire et al., 2006. Did the Transgondwanan Supermountain trigger the explosive radiation of animals on Earth? Earth and Planetary Science Letters 250, 116–133) postulated > 8000-km-long and > 1000-km-wide Transgondwanan Supermountains (TGSM) atop the EA-AO that resulted in extreme erosion and sedimentation rates; super-fans of quartz sand spread across continental North Africa-Arabia and oceanic crust offshore East Gondwanaland, as seawater 87 Sr/ 86 Sr rose to a maximum. Downslope indicators and the isotopic signature confirm the suggested deposition of the enormous North African-Arabian Super-fan from the Oubanguides Orogen-TGSM (Burke et al., 2003. Africa's petroleum systems: four tectonic ‘Aces’ in the past 600 million years. Geological Society of London Special Publications 207, 21–60), and the Cape Group from the TGSM. Other major provenance → sink relations are the Oubanguides Orogen → Congo Basin and the Damara Orogen and Dom Feliciano Orogens → Nama Basin. Minor and proximal provenance → sink relations are the Tuareg Shield and the Dahomeyides-Nigerian Shield → Volta Basin, and the Paraguay Orogen → Puncoviscana Basin. The voluminous primary sediment deposited during the Ediacaran, Cambrian, and Ordovician was recycled many times up to its present-day appearance in river and beach sand in Africa and in Australia . Compared with 60–0 Ma (~ Cenozoic) collisional Himalaya-Tibet and Mongolian Plateaus and related sediment fans of East Asia, the 700–500 Ma (Ediacaran–Cambrian) collisional continental super-fan in North Africa and Arabia and the deep-sea super-fan off East Gondwanaland are larger in extent and in their impact on seawater 87 Sr/ 86 Sr, probably because West Gondwanaland underwent crustal shortening over a much longer span; furthermore, the ancient morphotectonic regime lasted to the Carboniferous/Permian (~ 300 Ma) merger of Gondwanaland and Laurussia in Pangea, which instituted widespread Pangean-induced subsidence in broad basins that overlapped the planed-off orogens. [ABSTRACT FROM AUTHOR]

The Muang Xai Basin, located in northern Laos, is associated with the Simao, Vientiane, and Khorat Basins. The paleogeographic link of these basins has not been investigated in great detail; thus, the investigation presented in this study is a comprehensive analysis of petrology, whole-rock geochemistry, and detrital zircon U-Pb chronology used to characterize the provenance of the Muang Xai Basin. Results suggest that the sedimentary source includes felsic rocks from an active continental margin or continental arc with minor amounts of recycled passive continental margin sediments. Sandstones of the Muang Xai Basin contain detrital zircons with varying U-Pb peak ages. The youngest age peak of all the zircons is 103 Ma, which limits the age of the Mesozoic strata to the Late Cretaceous. Detrital zircon U-Pb and trace element data, combined with geochemical result, reveal that the pre-Ordovician zircons were derived from recycled sediments of the Yangtze Block, which are originally sourced from the Qinling Orogenic belt. This provenance is shared with coeval sediments in the Simao and Khorat Basins, while magmatic rocks of the Ailaoshan, Truong Son Belt, and Lincang terrane are responsible for zircons of 416-466 and 219-308 Ma in age. Zircons of 101-110 and 149-175 Ma in age were sourced from magmatic rocks of the southwestern South China Block and northern Vietnam. These provenance results suggest that sediments flow into the Khorat red beds was likely from the Great Simao Basin and northern Vietnam, and not directly from the Yangtze Block. [ABSTRACT FROM AUTHOR]

Elba Island, located midway between Corsica and mainland Italy, is a small but important fragment of the Adria Plate. It has a rich sedimentary record preserved in a stack of tectonic nappes of both continental margin and oceanic origin. Especially the detrital zircons in early Paleozoic to early Mesozoic metasedimentary rocks provide an archive of many important geological events in the island's history. Elba Island and Adria originated along the northern margin of Gondwana, but drifted north in Silurian times to become part of Europe. A large new dataset of LA-ICP-MS and SIMS U–Pb zircon ages allows us to trace this history. Three main stratigraphic units have been investigated. The oldest Porto Azzurro Unit was deposited in the early Cambrian and has zircon age distributions indicating a typical northern African provenance, most likely sourced from the Saharan Metacraton. The Ortano Unit has a simple, mostly unimodal Ordovician age distribution that is entirely dominated by metavolcanic rocks and their erosional products; a sample of the metavolcanic Ortano Porphyroids provided a SIMS U–Pb zircon age of 460 ± 3 Ma. This phase of intense volcanism is related to the subduction of the Rheic Ocean beneath Gondwana, terminating with initial rifting and subsequent opening of the Paleotethys. This also marks the onset of the separation of a range of European terranes, including Adria and future Elba Island, from Gondwana. The Permo-Triassic Monticiano–Roccastrada Unit is the first to show a European provenance with the appearance of large amounts of Variscan and late to post-Variscan detritus. The presence of Variscan detrital zircons in the Permo-Triassic sediments is unexpected, since a Variscan age signature is so far not well recorded in the Adria Plate. This dataset is the most comprehensive detrital zircon dataset so far available for the Adria Plate and documents Adria's close affinity to Africa in the Lower Paleozoic, as well as its initial rifting within an active continental margin setting during the Ordovician and its final separation and independent evolution since late Palaeozoic times. [ABSTRACT FROM AUTHOR]

The present study aims at tracking sediment provenance for a Mesoproterozoic craton-margin basin in eastern India, i.e. the Ampani Basin. Occurring on the eastern flank of the Archean Bastar Craton, the basin occupies a very strategic geographic position coinciding with the boundary between Archean craton and a Proterozoic orogenic belt with spatially varied tectonothermal history. The studied basin succession includes unmetamorphosed siliciclastic sediments deposited under three different environmental set-up viz . fluvial, shoreface and shelf. The basin sediment package defines a fining-upward succession with fluvial products at its base, shoreface deposits in the middle and shelf sandstone–siltstone–shale sediments at the top. In this study sandstone–siltstone and shale units encompassing the entire basin succession are analyzed geochemically and with U–Pb detrital zircon geochronology in order to characterize the sediment source/s. The basin was fed mainly by the Paleoarchean to late Paleoproterozoic granitoid source with minor contribution from mafic source particularly at the closing part of its depositional history. Except for relative enrichment, REE and trace element patterns of the three arenaceous units, viz . fluvial, shoreface, shelf sandstone are quite similar. U–Pb analysis of detrital zircon grains from the three units indicate that in the initial phase of basin deposition, sediments were sourced from Paleo- to Neoarchean and Palaeoproterozoic (with an age spread from ca . 3700 to 2400 Ma) provenance. From the middle shoreface part upwards, the Paleo- to Neoarchean sources fade away and a new Mesoproterozoic source ( ca . 2000–1700 Ma) was added with the continued Paleoproterozoic source/s. The youngest zircon populations of the three analyzed units yield an upper age limit of sedimentation at 2079 ± 44 Ma (lower being close to 1446 ± 21 Ma, as evident from the age of tuffaceous rocks on the middle shoreface part of the basin). The change in detrital zircon age spectra from the middle part of the stratigraphy might be due to some basin-adjacent tectonic activities. [ABSTRACT FROM AUTHOR]

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; εHf +10 to −20) and 1300–1000 Ma ages (T DM C 2.7–1.3 Ga; εHf +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. [ABSTRACT FROM AUTHOR]

A representative suite of detrital zircons from the Cenozoic Namakwa Sands heavy mineral placer deposit, which is hosted by mainly unconsolidated clastic sediments of the West Coast Group, has been studied from a provenance perspective. The deposit is located along the west coast of South Africa and is underlain by a metamorphosed Meso- and Neoproterozoic basement. Mineral geochemistry of individual zircon grains indicated that the entire population is continentally derived and is dominated by zircons from a felsic magmatic source, some highly evolved, with minor contributions from a metamorphic and mafic provenance. The U–Pb zircon age distribution is diverse, but is dominated by three distinct age populations. The 1100–1020 Ma interval can be equated with the felsic meta-intrusives of the Namaquan Orogeny of the Namaqualand Metamorphic Province, and the 650–500 Ma period with the meta-volcanosedimentary Pan-African Gariep and Saldania Belts. A particularly dominant group with a narrow time interval (145–130 Ma) is correlated with the proximal intrusives of the anorogenic Koegel Fontein Complex. Equivalent source rocks of the above time intervals occur proximal to the Namakwa Sands deposit. As a result, it was demonstrated that the Namakwa Sands zircon population has mainly a proximal, primary provenance, whereas contributions attributed to secondary, reworked or distal sources proved minor. The high concentration and quality of zircons in this deposit compared to similar placers globally is attributed to the proximity of a primary, zircon-rich provenance to a geomorphologically controlled depositional trap. The results of the study suggest that the contribution of Pan-African (750–500 Ma) sources is a key prerequisite in the successful exploration for similar high-quality zircon placer deposits along the west coast of South Africa. [ABSTRACT FROM AUTHOR]

Abstract: The Late Cretaceous Mengyejing Formation, which contains the only pre-Quaternary potash salt deposit in the Simao Basin, southeastern Tibet, is thought to be genetically related to the Maha Sarakham Formation in the Khorat Basin. The provenance and paleogeography of these two basins have been under debate, although little diagnostic evidence has been previously published. A combined analysis of whole rock geochemistry, zircon U–Pb chronology, and Hf isotopic compositions was performed to characterize the provenance of the Mengyejing Formation. These formation's sandstones are characterized by moderate chemical index of alteration (CIA) values. These values, together with plots of the Th/U–Th ratios, suggest that certain samples have undergone moderate weathering and sedimentary recycling. The major and trace elements (La/Th–Hf, Th/Sc–Zr/Sc, Eu/Eu*–Th/Sc, TiO2–Fe2O3 T +MgO, Al2O3/SiO2–Fe2O3 T +MgO, K2O/Na2O–SiO2) indicate that the sedimentary sources were felsic rocks from an active continental margin or continental arc with a minor amount of recycled sediment from a passive continental margin. The Mengyejing Formation contains detrital zircons primarily with U–Pb ages of 2.45–2.57Ga, 1.8–1.9Ga, 740–880Ma, 410–470Ma, and 215–300Ma. The results reveal that the pre-Devonian zircons are derived from the recycled sediments of the Yangtze block originating in the Qinling Orogenic Belt, and they share this provenance with the coeval sediments in the Khorat Basin. The magmatic rocks of the Ailaoshan and Lincang areas are responsible for supplying the Devonian to Triassic detrital zircons. These provenance data combined with published paleocurrent results suggest that the Simao Basin was situated on the western margin of the Khorat Basin during the Late Cretaceous. The basins were connected when marine incursion occurred. We propose that pre-Devonian materials from the southwestern Sichuan Basin first supplied detritus to the Simao Basin and subsequently to the Khorat Basin. [Copyright &y& Elsevier]

Qamdo basin is located between the suture zone of Jinsha River (Ailao Mountains) and that of Ban Gong Lake (Nujiang) in the eastern Tethys. Part of the Jingxing Formation is deposited in the southwest of the basin. In this study, two profiles were investigated from the north and south of Qamdo basin. The characteristics of detrital zircon LA-ICP-MS U-Pb age, and the main and trace elements of sandstone were analyzed. The characteristics of major and trace elements showed that the tectonic setting of the study area is mainly composed of a relatively stable active continental margin and a passive continental margin, showing characteristics of a continental island arc. The weathering degree of Jingxing Formation in the Qamdo area is lower than that in the Lanping-Simao area, which may be closer to the origin. The age distribution characteristics of detrital zircon grains indicate that the Qiangtang Block, Youjiang basin, and Yangtze area jointly constitute the provenance of the Qamdo-Lanping-Simao basin. Both basins may be part of a large marine basin with unified water conservancy connection before evaporite deposition. Metamorphic seawater from the Qamdo basin may migrate to the Lanping-Simao basin and even the Khorat basin, where evaporite was deposited. [ABSTRACT FROM AUTHOR]