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This study presents Lu–Hf data on detrital zircon grains from the Lower Paleozoic metasedimentary successions of the Sierra Albarrana Domain (SW Iberian Massif). We provide new information about their origin, record of continental crustal evolution and geological affinity. Previous detrital zircon U–Pb data in this terrane reveal two main age populations, with age peaks at c. 595 Ma and c. 1.90 Ga. The Ediacaran events are interpreted to represent a magmatic arc with input of juvenile magmas intruding into the Eburnean basement of Gondwana, and probably mixing with it. The different evolutionary stages of the arc were probably linked to the Cadomian Orogeny during Neoproterozoic–earliest Cambrian times. The Paleoproterozoic zircon population corresponds to the Eburnean Orogeny. The magmas derived from an Eburnean depleted mantle partly intruded an older basement, leading to an incipient mixing process. ε Hf isotopic compositions indicate a possible affinity with the Central Iberian Zone, suggesting a common geological setting during Ediacaran–Cambrian times but different settings during the Paleoproterozoic. Supplementary material: A dataset of Lu/Hf analyses and a regional comparison of the ε Hf(t) dataset with published data for metasedimentary rocks of the Iberian Massif are available at https://doi.org/10.6084/m9.figshare.c.6420215 [ABSTRACT FROM AUTHOR]

The upper Beetaloo Sub-basin of the McArthur Basin, Northern Territory, Australia, records over 500 myr of tectonic history of the North Australian Craton from c. 1.45 to 0.9 Ga. The basin sequences include shallow-water clastic sedimentary rocks that preserve the oldest global commercial hydrocarbon reserves. New detrital zircon U-Pb age and Lu-Hf isotopes, compiled with published data, provide constraints on the basin provenance and reveal the dynamic tectonic evolution of Mesoproterozoic northern Australia. Data from the oldest formation examined, the c. 1.4 Ga Bessie Creek Sandstone, suggest provenance from (present-day) eastern sources (e.g. the Mount Isa Province and the palinspastically adjacent Curnamona and Georgetown provinces) with considerable spatial heterogeneity. These eastern source regions are interpreted as uplifted rift-shoulder highs, formed by contemporaneous extension between Proterozoic Australia and Laurentia. Progressively younger formations (the Velkerri Formation, the Moroak Sandstone and the Kyalla Formation) demonstrate a rapid swamping of the basin by detritus from southerly sources (e.g. the Arunta Region) that occurred at c. 1.4-1.3 Ga. This is particularly characterized by the up-section reduction of c. 1.6-1.5 Ga detrital zircon grains. This change in provenance is interpreted to relate to closure of an ocean basin during the period 1.35-1.25 Ga, which resulted in uplift of the southern margin of the North Australia Craton. Three ungrouped latest Mesoproterozoic to Neoproterozoic sedimentary units, the lower and upper Jamison sandstone and the Hayfield mudstone, were deposited after the emplacement of theWarakurna Large Igneous Province and are sourced from the Musgrave Province. Detrital zircon U-Pb and Hf isotope affinities between the lower and upper Jamison sandstone and the Hayfield mudstone and the latest Mesoproterozoic to early Neoproterozoic successions along the eastern margin of the North China Craton suggest that they share a similar provenance. This supports correlations between the Mesoproterozoic of the North China Yanshan Basin and the greater McArthur Basin. [ABSTRACT FROM AUTHOR]

Decoding the crustal and tectonic evolution of ancient accretionary orogens is not always straightforward. Here, four episodes of Paleozoic granitoids have been identified with distinct zircon–Hf isotopic characteristics from the Northeastern Tianshan. The first stage granitoids in the Dananhu–Harlik arc system are characterized by highly positive zircon εHf(t) values and short crustal incubation times with a rising event signature, suggesting a northward trench advance for the Kangguer Ocean. During the second stage, granitoids in the Dananhu and Kangguer belts have high zircon εHf(t) values and short crustal incubation times, but with a decreasing event signature for the Dananhu granitoids, implying a reworking of the juvenile arc crust. However, the near-zero εHf(t) values and the longest crustal incubation times of the Yamansu granitoids in this stage elucidate an origin from a Precambrian basement. These variations suggest that the northern trench of the Kangguer Ocean retreated southward while the southern trench advanced southward. During the third stage, the enlarged ranges of zircon εHf(t) values and crustal residence ages as well as crustal incubation times for the Dananhu and Kangguer granitoids show an interaction of juvenile material and the pre-existing crust, whereas the highly positive zircon εHf(t) values with a sharp rising event signature of the Yamansu granitoids suggest an significant crustal growth, indicating that a northward trench advance and a southern trench retreat for the Kangguer Ocean. However, the last stage granitoids in the Northeastern Tianshan entirely exhibit decreasing zircon εHf(t) values and long crustal incubation times, demonstrating a reworking of the pre-existing juvenile crust with minor input of ancient crustal materials in a post-collisional setting. Supplementary material: Table S1 and S2 and analytical methods are available at https://doi.org/10.6084/m9.figshare.c.5197889 [ABSTRACT FROM AUTHOR]